JP7329026B2 - Nondestructive inspection device and nondestructive inspection method based on threshold analysis - Google Patents

Description

The present invention relates to a non-destructive inspection apparatus and a non-destructive inspection method for non-destructive inspection of the state of grout filling in a sheath pipe embedded in a concrete structure such as a PC bridge based on threshold analysis using broadband ultrasonic waves.

Prestressed concrete structures (see FIG. 49) manufactured by the post-tension construction method are used for main girders, side walls, floor slabs, etc. of bridges on roads and railways.
In this prestressed concrete structure, after the poured concrete has hardened, the PC steel material in the sheath pipe preliminarily placed in the concrete is tensed and fixed to the concrete, thereby generating residual compressive stress in the concrete. there is

As a result, prestressed concrete structures are superior in durability to tensile loads and lighter in weight than reinforced concrete structures, making it possible to construct large-scale buildings with longer spans.

By the way, in such a prestressed concrete structure, the sheath pipe is filled with a grout material such as cement milk in order to prevent the tensioned PC steel from rusting. For this reason, it was necessary to check the state of grout filling in prestressed concrete structures.

In particular, when the grout is not filled or is insufficiently filled, the PC steel material may corrode and break due to rainwater entering the sheath pipe after many years, and the desired durability may not be ensured. . For example, in Japan and overseas PC bridges, several serious accidents such as bridge collapses have actually occurred.

Therefore, a nondestructive inspection apparatus and a nondestructive inspection method for nondestructively inspecting the grout filling state of a sheath pipe embedded in a prestressed concrete structure have been proposed and put into practical use (see Patent Documents 1 and 2). .

These days, when a PC bridge is newly constructed, a non-destructive inspection device developed based on Patent Document 1 is used to non-destructively inspect the filling state of grout in the sheath pipe from the concrete surface.
Furthermore, in existing PC bridges, a non-destructive inspection of the state of grout filling is performed with a non-destructive inspection device using WUT software, which is an improvement and development of the methods described in Patent Documents 1 and 2.

By the way, in the non-destructive inspection using this WUT software, the case where the distance between the centers of the transmitting probe and the receiving probe is 110 to 200 mm is called reflected P-wave measurement analysis. When the center-to-center distance to the child is 375 mm or more, it is called reflected S-wave measurement analysis.

However, it has been confirmed that non-destructive inspection using WUT software has various problems.
For example, in the case of reflected P-wave measurement analysis, the following four problems have been confirmed.
The first problem is that the sheath cover thickness and the measurement accuracy of the concrete longitudinal wave sound velocity not only affect the analysis accuracy of the grout filling state, is not uncommonly misanalyzed as "unfilled".

As a second problem, when the sheath cover thickness is shallow, a large amplitude concrete surface _S1 wave and a direct wave are generated before the time of occurrence of the sheath reflected P wave, and after the time of occurrence of the sheath reflected P wave. In addition, the reflected waves from the second sheath, the plate thickness, and the bottom corner of the plate thickness reduce the analysis accuracy of the grout filling state, and misanalyze "complete filling" as "unfilled". Events are not rare.

As a third problem, the measurement point happens to be located directly above the boundary between the grout unfilled part and the grout filled part. is not uncommonly misanalyzed as "completely filled".
As a fourth problem, the sheath cover thickness may change greatly in the longitudinal direction of the sheath tube, and due to this, even if the grout filling state is "unfilled", it may not be "completely filled". Misanalyses are not uncommon.

In the case of reflected S-wave measurement analysis, the following five problems have been confirmed.
The first problem is that the analysis accuracy of the grout filling state depends on the sheath cover thickness and the measurement accuracy of the concrete longitudinal wave speed.
As a second problem, the surface _S1 wave occurs before the occurrence time of the analysis cutting wave used in the analysis of the sheath reflected S wave, and the second stage sheath and plate are behind the occurrence time of the analysis cutting wave. Reflected waves from the corners of the thickness and bottom of the slab reduce the accuracy of the analysis of the grout filling state, and it is not uncommon for erroneous analysis of "complete filling" to be "unfilled".

The third problem is that the measurement point happens to be located directly above the boundary between the grout unfilled part and the grout filled part. is not uncommonly misanalyzed as "completely filled".
As a fourth problem, the sheath cover thickness may vary greatly in the longitudinal direction of the sheath tube. Even if it is "unfilled", it is erroneously analyzed as "completely filled".

As a fifth problem, in the case of concrete, the sound speed ratio between the P wave and the S wave is about 0.62, so the time band of occurrence of the sheath reflected S wave is later than the sheath reflected P wave. Move to As a result, the reflected waves from the second sheath, the plate thickness, and the bottom corner of the plate thickness are mixed in with the sheath reflected S wave, which reduces the analysis accuracy of the grout filling state, and the grout filling state becomes "complete." Even if it is "filled", it is often erroneously determined as "unfilled" or "insufficient filling".

In order to deal with the various problems mentioned above, in the non-destructive inspection using WUT software, the analysis results are acquired by the analysis processing by the analysis operator who deals with the above problems by spending several times the number of days of measurement. However, there are many incidents in which none of the analysis operators can reliably derive the correct grouting condition.
For this reason, non-destructive inspection using WUT software is required to improve the efficiency and accuracy of grout filling state analysis.
Therefore, the applicant creates a spectrum and time series used in analysis by a processing method named threshold processing, and uses this to solve the above-mentioned many problems. is creating

Japanese Patent No. 4640771 Japanese Patent No. 5814582

In view of the above-mentioned problems, the present invention provides a nondestructive inspection apparatus using sheath reflected P waves and a nondestructive inspection method using sheath reflected P waves that can efficiently and accurately nondestructively inspect the grout filling state. intended to

前記発信探触子から前記計測対象シースに向かって、所定時刻間隔で超音波を連続発信し、発信のたびに前記受信探触子で得た収録波を加算平均して測点ｉ毎の受信波Ｇ（ｔ）｜_{ｉ＝１～ｎｗ}を取得し、該受信波Ｇ（ｔ）｜_{ｉ＝１～ｎｗ}をＦＦＴ変換して対応する受信波スペクトルＦ（ｆ）｜_{ｉ＝１～ｎｗ}を取得する第２の収録手段と、振動数０．０から（ｆ_ｓ－Δｆ_ｓ）の間が「０．０」、振動数（ｆ_ｓ－Δｆ_ｓ）からｆ_ｓの間が「０．０から１．０」となるｓｉｎ形状増加関数、振動数ｆ_ｓから（ｆ_ｓ＋Δｆ_ｓ）の間が「１．０から０．０」となるｓｉｎ形状減少関数、振動数（ｆ_ｓ＋Δｆ_ｓ）以上で「０．０」となる関数をＦ３フィルタ関数として、該Ｆ３（ｆ）フィルタ関数の中心振動数ｆ_ｓを低振動数または高振動数側へ徐々に移動させるオペレータの操作を受け付ける操作受付手段と、Δｔ_ｋをオペレータによって設定される値とし、時刻０．０から（ｔ_ｐ｜_ＲＣ－Δｔ_ｋ）の間が「０．０」、時刻（ｔ_ｐ｜_ＲＣ－Δｔ_ｋ）で「０．０」となり時刻ｔ_ｐ｜_ＲＣで「１．０」となるｓｉｎ形状増加関数、時刻ｔ_ｐ｜_ＲＣで「１．０」となり時刻（ｔ_ｐ｜_ＲＣ＋Δｔ_ｋ）で「０．０」となるｓｉｎ形状減少関数、時刻（ｔ_ｐ｜_ＲＣ＋Δｔ_ｋ）以降で「０．０」となる関数を時刻フィルタ関数ＴＧＣ４（ｔ）として、前記操作受付手段でオペレータの操作を受け付けるたびに、前記中心振動数ｆ_ｓとする前記Ｆ３（ｆ）フィルタ関数を前記受信波スペクトルＦ（ｆ）｜_{ｉ＝１～ｎｗ}に乗じて得たスペクトルをＦＦＴ逆変換して得る時系列波に対して、該時系列波のいずれかの測点ｉの起生時刻を中心時刻とする前記時刻フィルタ関数ＴＧＣ４（ｔ）を乗じて、分析用１次反射Ｐ波起生時刻ｔ_ｐ（１）｜_{ｉ＝１～ｎｗ}を取得するとともに、下式のｄｓを分析用１次かぶり厚ｄｓ_（１）｜_ｉに、下式のｔ_ｐを前記分析用１次反射Ｐ波起生時刻ｔ_ｐ（１）｜_ｉに置き換えて、分析用１次かぶり厚ｄｓ_（１）｜_ｉを取得し、

さらに、測点ｉ＝１～ｎｗの多点計測における前記分析用１次かぶり厚ｄｓ_（１）｜_ｉが全ての測点ｉで同一の場合、前記分析用１次反射Ｐ波起生時刻ｔ_ｐ（１）｜_ｉ、及び前記分析用１次かぶり厚ｄｓ_（１）｜_ｉをそれぞれｔ_ｐ（１）、及びｄｓ_（１）とするとともに、開始測点ｎＡをｉ＝１、終了測点ｎＢをｉ＝ｎｗとし、測点ｉ＝１～ｎｗの多点計測における前記分析用１次かぶり厚ｄｓ_（１）｜_ｉが測点ｉごとに異なる場合、前記分析用１次反射Ｐ波起生時刻ｔ_ｐ（１）｜_{ｉ＝１～ｎｗ}を２つに区分し、それぞれの平均値をｔ_ｐ（１）｜_大、及びｔ_ｐ（１）｜_小とし、前記分析用１次反射Ｐ波起生時刻ｔ_ｐ（１）｜_大を上式に適用して得た分析用１次かぶり厚ｄｓ_（１）を分析用１次かぶり厚ｄｓ_（１）｜_大とし、前記分析用１次反射Ｐ波起生時刻ｔ_ｐ（１）｜_小を上式に適用して得た分析用１次かぶり厚ｄｓ_（１）を分析用１次かぶり厚ｄｓ_（１）｜_小として、前記分析用１次かぶり厚ｄｓ_（１）｜_大及びｄｓ_（１）｜_小ごとの開始測点ｎＡ、及び終了測点ｎＢを取得する第１の分析手段と、中心振動数ｆ_０を２０ｋＨｚ、振動数ｆ_ｗをオペレータによって設定される５０ｋＨｚ－Δｆ_ｗ＜ｆ_ｗ＜５０ｋＨｚ＋Δｆ_ｗ（ただし、Δｆ_ｗ＝５ｋＨｚ）の範囲のいずれかの値、振動数ｆ_２を８０ｋＨｚとして、振動数－１０ｋＨｚからｆ_０が「０．０から１．０」となるｓｉｎ形状増加関数、振動数ｆ_０からｆ_ｗが「１．０から０．０」となるｓｉｎ形状減少関数、振動数ｆ_ｗからｆ_２が「０．０から１．０」となるｓｉｎ形状増加関数、振動数ｆ_２から（ｆ_２＋３０ｋＨｚ）が「１．０から０．０」となるｓｉｎ形状減少関数、振動数（ｆ_２＋３０ｋＨｚ）以上で「０．０」となるＡ_Ｋ（ｆ）フィルタ関数を、ｉ＝１～ｎｗを受信波、ｉ＝ｎｗ＋１を加算平均波とする受信波スペクトルＦ（ｆ）｜_{ｉ＝１～ｎｗ＋１}に乗じて分析用スペクトルＦＡ（ｆ）｜_{ｉ＝１～ｎｗ＋１}を取得し、該分析用スペクトルＦＡ（ｆ）｜_{ｉ＝１～ｎｗ＋１}をＦＦＴ逆変換して対応する分析用時系列ＧＡ（ｔ）｜_{ｉ＝１～ｎｗ＋１}を取得する第２の分析手段と、ｉ＝１～ｎｗの多点計測における前記分析用１次かぶり厚ｄｓ_（１）｜_ｉが同一の場合、前記分析用１次反射Ｐ波起生時刻ｔ_ｐ（１）｜_ｉをｔ_ｐ（１）とし、前記分析用１次かぶり厚ｄｓ_（１）｜_ｉをｄｓ_（１）として、第３の分析手段、第４の分析手段、第５の分析手段、第６の分析手段、第７の分析手段、及び第８の分析手段による分析によって、前記計測対象シースのグラウト充填状態を判定する第１の処理手段と、ｉ＝１～ｎｗの多点計測における前記分析用１次かぶり厚ｄｓ_（１）｜_ｉが異なる場合、前記分析用１次反射Ｐ波起生時刻ｔ_ｐ（１）をｔ_ｐ（１）｜_大に、前記分析用１次かぶり厚ｄｓ_（１）をｄｓ_（１）｜_大に置き換えた前記第３の分析手段、前記第４の分析手段、前記第５の分析手段、前記第６の分析手段、前記第７の分析手段、及び前記第８の分析手段による分析によって、前記分析用１次かぶり厚ｄｓ_（１）｜_大における前記計測対象シースのグラウト充填状態を判定する第２の処理手段と、該第２の処理手段での判定に引き続いて、前記分析用１次反射Ｐ波起生時刻ｔ_ｐ（１）をｔ_ｐ（１）｜_小に、前記分析用１次かぶり厚ｄｓ_（１）をｄｓ_（１）｜_小に置き換えた前記第３の分析手段、前記第４の分析手段、前記第５の分析手段、前記第６の分析手段、前記第７の分析手段、及び前記第８の分析手段による分析によって、前記分析用１次かぶり厚ｄｓ_（１）｜_小における前記計測対象シースのグラウト充填状態を判定する第３の処理手段とを備え、前記第３の分析手段は、時刻ｔ_ｐ（１）＋Δｔ_ｈ１を基準時刻とする時刻フィルタ関数ＴＧＣ１（ｔ）、及び時刻ｔ_ｐ（１）を基準時刻とする時刻フィルタ関数ＴＧＣ２（ｔ）を、前記分析用時系列ＧＡ（ｔ）｜_{ｉ＝１～ｎｗ＋１}に乗じて分析用切り出し波ＧＢ_（１）（ｔ）｜_{ｉ＝１～ｎｗ＋１}を取得し、該分析用切り出し波ＧＢ_（１）（ｔ）｜_{ｉ＝１～ｎｗ＋１}をＦＦＴ変換して対応するスペクトルＦＢ_（１）（ｆ）｜_{ｉ＝１～ｎｗ＋１}を取得する分析手段であり、前記時刻フィルタ関数ＴＧＣ１（ｔ）は、基準時刻ｔ_ｈ＝ｔ_ｐ（１）＋Δｔ_ｈ１として、時刻ｔ＝０で「０．０」となり、基準時刻ｔ_ｈで「１．０」となるｓｉｎ形状増加線分、時刻ｔ＝基準時刻ｔ_ｈ以降が「１．０」となるＴＧＣＡ（ｔ）関数を用いて、（ＴＧＣＡ（ｔ））^ｎｅで算出される関数であり、前記時刻フィルタ関数ＴＧＣ２（ｔ）は、基準時刻ｔ_ｈ＝ｔ_ｐ（１）として、時刻ｔ＝０．０から時刻ｔ＝ｔ_ｈが「１．０」、時刻ｔ＝基準時刻ｔ_ｈで「１．０」となり、時刻ｔ＝４００μ秒で「０．０」となるｓｉｎ形状減少線分、時刻ｔ＝４００μ秒以降が「０．０」となるＴＧＣＢ（ｔ）関数を用いて、（ＴＧＣＢ（ｔ））^ｎｆで算出される関数であり、前記第４の分析手段は、前記スペクトルＦＢ_（１）（ｆ）｜_{ｉ＝１～ｎｗ＋１}で、ｉごとに前記振動数ｆ_ｗよりも低振動数側の最大スペクトル値を基準値＝１．０としたのち、前記振動数ｆ_ｗよりも高振動数側の最大スペクトル値を閾値α_σとする閾値処理で、分析用１次スペクトルＦＣ_（１）（ｆ）｜_{ｉ＝１～ｎｗ＋１}を取得し、該分析用１次スペクトルＦＣ_（１）（ｆ）｜_{ｉ＝１～ｎｗ＋１}に対応する分析用１次時系列ＧＣ_（１）（ｔ）｜_{ｉ＝１～ｎｗ＋１}をＦＦＴ逆変換で取得する分析手段であり、前記第５の分析手段は、台形窓関数Ａを時刻ｔ_始＝ｔ_ｐ（１）－Δｔ_ｐ１から時刻ｔ_終＝ｔ_ｐ（１）＋Δｔ_ｐ２までΔｔ_ａ間隔で移動させるたびに、前記分析用１次時系列ＧＣ_（１）（ｔ）｜_{ｉ＝１～ｎｗ＋１}に台形窓関数Ａを乗じて切り出した時系列に対応するスペクトルを求め、前記振動数ｆ_ｗ以下での最大スペクトル値を１．０に基準化して得たスペクトルにおいて、前記振動数ｆ_ｗ以上での最大スペクトル値を時刻掃引基準化スペクトル値ＳＰ_ｆ２として、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_{ｉ＝１～ｎｗ＋１}を作成するとともに、前記振動数ｆ_ｗ以上、及び前記振動数ｆ_ｗ以下での最大スペクトル値を時刻の推移毎に比較して大きい方の最大スペクトル値を１．０に基準化して得た時刻掃引ｆ_０，ｆ_２スペクトルＳＰ_{ｆ２（１）}（ｆ，ｔ）^ｎｃ｜_{ｉ＝１～ｎｗ＋１}を作成する分析手段であり、前記台形窓関数Ａは、基準時刻をｔ_始とし、前記分析用１次かぶり厚ｄｓ_（１）またはｄｓ_（１）｜_大あるいはｄｓ_（１）｜_小に応じて設定された時間幅を示す値をｔ_ａとして、時刻ｔ＝０．０からｔ_始－５の間が「０．０」、時刻ｔ＝ｔ_始－５からｔ_始が「０．０」から「１．０」となるｓｉｎ形状増加関数、時刻ｔ＝ｔ_始からｔ_始＋ｔ_ａが「１．０」、時刻ｔ＝ｔ_始＋ｔ_ａからｔ_始＋ｔ_ａ＋５が「１．０」から「０．０」となるｓｉｎ形状減少関数、時刻ｔ＝ｔ_始＋ｔ_ａ＋５以降が「０．０」となる関数であり、前記第６の分析手段は、計測対象シースの空隙部分とグラウト充填部分との境界測点をｎ１として、第１の分析手段で取得した開始測点ｎＡ及び終了測点ｎＢを用いて、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_{ｉ＝ｎＡ～ｎＢ}のスペクトル値が、測点ｉ＝ｎＡ～ｎ１（ただし、境界測点ｎ１≦終了測点ｎＢ）において、時刻ｔ_ｐ（１）－Δｔ_Ｂ１から時刻ｔ_ｐ（１）＋Δｔ_Ｂ２の間で増加傾向にあり、時刻ｔ_ｐ（１）＋Δｔ_Ｂ２で閾値α_σを超えることを確認して前記境界測点ｎ１が特定される特性ＴＡ、または時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_{ｉ＝ｎＡ～ｎＢ}のスペクトル値が、測点ｉ＝ｎＡ～ｎ１（ただし、境界測点ｎ１≦終了測点ｎＢ）において、時刻ｔ_ｐ（１）＋Δｔ_Ｂ２で閾値α_σを下回ることを確認して前記境界測点ｎ１が特定される特性ＴＢのいずれであるかを特定する分析手段であり、前記第７の分析手段は、前記第６の分析手段において、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_{ｉ＝ｎＡ～ｎＢ}のスペクトル形状が特性ＴＡと特定された場合、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_{ｉ＝ｎＡ～ｎＢ}に基づいて、第１ＴＡ処理手段、及び第２ＴＡ処理手段による分析を行い、グラウト充填状態を判定する分析手段であり、前記第８の分析手段は、前記第６の分析手段において、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_{ｉ＝ｎＡ～ｎＢ}のスペクトル形状が特性ＴＢと特定された場合、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_{ｉ＝ｎＡ～ｎＢ}に基づいて、第１ＴＢ処理手段、及び第２ＴＢ処理手段による分析を行い、グラウト充填状態を判定する分析手段であり、前記第７の分析手段の前記第１ＴＡ処理手段は、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_ｉが、測点ｉ＝ｎＡ～ｎ１（ただし、ｎ１≦ｎＢ）ごとに時刻ｔ_ｐ（１）－Δｔ_Ｂ１と時刻ｔ_ｐ（１）＋Δｔ_Ｂ２の間で増加傾向にあり、時刻ｔ_ｐ（１）＋Δｔ_Ｂ２で閾値α_σを超えている時、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_{ｉ＝ｎＡ～ｎ１}（ただし、ｎ１≦ｎＢ）ごとに、時刻ｔ_ｐ（１）－Δｔ_Ｂ１と時刻ｔ_ｐ（１）＋Δｔ_Ｂ２との間で、閾値α_σを超える時刻をｔ_ｉとし、この平均値をｔ_Ａとして、下式に基づいてΔｔ_Ａを取得するとともに、

下式に基づいて分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）を取得し、

下式のｄｓを分析用２次かぶり厚ｄｓ_（２）に、下式のｔ_ｐを前記分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）に置き換えて分析用２次かぶり厚ｄｓ_（２）を取得し、

前記第３の分析手段、及び前記第４の分析手段における前記分析用１次反射Ｐ波起生時刻ｔ_ｐ（１）を分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）に置き換えて、前記第３の分析手段、及び前記第４の分析手段による再度の分析によって、分析用１次時系列ＧＣ_（１）（ｔ）｜_{ｉ＝１～ｎｗ＋１}の代わりに分析用２次時系列ＧＣ_（２）（ｔ）｜_{ｉ＝１～ｎｗ＋１}を作成し、さらに、前記第５の分析手段による再度の分析で前記分析用２次時系列ＧＣ_（２）（ｔ）｜_{ｉ＝１～ｎｗ＋１}に分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）を用いた前記台形窓関数Ａのｔ_ｐ（２）－Δｔ_ｐ１を始点時刻ｔ_始とし、ｔ_ｐ（２）＋Δｔ_ｐ２を終点時刻ｔ_終とする掃引処理を適用し、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝１～ｎｗ＋１}、及び時刻掃引ｆ_０，ｆ_２スペクトルＳＰ_{ｆ２（２）}（ｆ，ｔ）^ｎｃ｜_{ｉ＝１～ｎｗ＋１}を作成し、次に、ＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}を下式で作成し直すとともに、

前記ＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}のＦＦＴ変換でスペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を求め、さらに下式に基づいてスペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を作成し、

前記スペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}の位相情報を、前記スペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}の位相情報に変更したのち、前記スペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}のＦＦＴ逆変換でＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}を作成し、再々度の前記第５の分析手段による前記台形窓関数Ａのｔ_ｐ（２）－Δｔ_ｐ１を始点時刻ｔ_始とし、ｔ_ｐ（２）＋Δｔ_ｐ２を終点時刻ｔ_終とする掃引処理を前記ＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}に適用し、前記分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）とするＳＰ加算の時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝１～ｎｗ＋１}、及び時刻掃引ｆ_０，ｆ_２スペクトルＳＰ_{ｆ２（２）}（ｆ，ｔ）^ｎｃ｜_{ｉ＝ｎｗ＋１}を作成し直したのち、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝ｎＡ～ｎ１}とＳＰ加算の時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝ｎｗ＋１}とを用いて測点ｉ＝ｎＡ～ｎ１各々での、及びＳＰ加算ｉ＝ｎｗ＋１でのグラウト充填状態を、空充判定線分α^～ _σ（＝α_σ＋０．０６）値、及び前記分析用２次かぶり厚ｄｓ_（２）に応じて設定された時刻を＊値とする空充判定カーソルｔ_＊＝ｔ_ｐ（２）＋＊を用いて取得した時刻ｔ_＊での時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ_＊）｜_ｉが、α^～ _σ＋０．１８＜ＳＰ_{ｆ２（２）}（ｔ_＊）｜_ｉの場合に「未充填」と自動判定し、α^～ _σ＜ＳＰ_{ｆ２（２）}（ｔ_＊）｜_ｉ≦α^～ _σ＋０．１８の場合に「充填不足」と自動判定し、該判定結果及び時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝１～ｎｗ＋１}を表示部に表示する処理手段であり、前記第７の分析手段の前記第２ＴＡ処理手段は、ｎ１＜ｎＢの場合において、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_ｉが測点ｉ＝ｎ１＋１～ｎＢごとに、時刻ｔ_ｐ（１）＋Δｔ_Ｂ２で閾値α_σを下回る時、時刻ｔ_ｐ（１）＋Δｔ_Ｂ２のさらなる時刻後方で、測点ｉ＝ｎ１＋１～ｎＢの時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_ｉが閾値α_σを超える時刻をｔ_ｉとして、下式を満足させる測点ｉの時刻ｔ_ｉを選定し、該時刻ｔ_ｉの平均値を時刻平均値ｔ_Ａとし、

上式を満足させる時刻ｔ_ｉがない場合、時刻平均値ｔ_Ａ＝ｔ_{Ｍ１（１）}として、下式でΔｔ_Ａを求め、

分析用２次シース反射Ｍ_１波起生時刻ｔ_{Ｍ１（２）}及び分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）を下式群に基づいて取得するとともに、

下式のｄｓを分析用２次かぶり厚ｄｓ_（２）に、下式のｔ_ｐを前記分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）に置き換えて、分析用２次かぶり厚ｄｓ_（２）を取得し、

前記第３の分析手段、及び前記第４の分析手段における前記分析用１次反射Ｐ波起生時刻ｔ_ｐ（１）を分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）に置き換えて、前記第３の分析手段、及び前記第４の分析手段による再度の分析によって、分析用１次時系列ＧＣ_（１）（ｔ）｜_{ｉ＝１～ｎｗ＋１}の代わりに分析用２次時系列ＧＣ_（２）（ｔ）｜_{ｉ＝１～ｎｗ＋１}を作成し、さらに、前記第５の分析手段による再度の分析で前記分析用２次時系列ＧＣ_（２）（ｔ）｜_{ｉ＝１～ｎｗ＋１}に分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）を用いた前記台形窓関数Ａのｔ_ｐ（２）－Δｔ_ｐ１を始点時刻ｔ_始とし、ｔ_ｐ（２）＋Δｔ_ｐ２を終点時刻ｔ_終とする掃引処理を適用し、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝１～ｎｗ＋１}、及び時刻掃引ｆ_０，ｆ_２スペクトルＳＰ_{ｆ２（２）}（ｆ，ｔ）^ｎｃ｜_{ｉ＝１～ｎｗ＋１}を作成し、次に、ＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}を下式で作成し直すとともに、

前記ＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}のＦＦＴ変換でスペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を求め、さらに下式に基づいてスペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を作成し、

前記スペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}の位相情報を、前記スペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}の位相情報に変更したのち、前記スペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}のＦＦＴ逆変換でＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}を作成し、再々度の前記第５の分析手段による前記台形窓関数Ａのｔ_ｐ（２）－Δｔ_ｐ１を始点時刻ｔ_始とし、ｔ_ｐ（２）＋Δｔ_ｐ２を終点時刻ｔ_終とする掃引処理を前記ＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}に適用し、前記分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）を用いたＳＰ加算の時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝１～ｎｗ＋１}、及び時刻掃引ｆ_０，ｆ_２スペクトルＳＰ_{ｆ２（２）}（ｆ，ｔ）^ｎｃ｜_{ｉ＝ｎｗ＋１}を作成し直したのち、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝ｎ１＋１～ｎＢ}とＳＰ加算の時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝ｎｗ＋１}とを用いて測点ｉ＝ｎ１＋１～ｎＢ各々での、及びＳＰ加算ｉ＝ｎｗ＋１でのグラウト充填状態を、空充判定線分α^～ _σ（＝α_σ＋０．０６）値、及び前記分析用２次かぶり厚ｄｓ_（２）に応じて設定された時刻を＊値とする空充判定カーソルｔ_＊＝ｔ_ｐ（２）＋＊を用いて取得した時刻ｔ_＊での時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ_＊）｜_ｉが、ＳＰ_{ｆ２（２）}（ｔ_＊）｜_ｉ≦α^～ _σの場合に「完全充填」と自動判定し、該判定結果及び時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝１～ｎｗ＋１}を表示部に表示する処理手段であり、前記第８の分析手段の前記第１ＴＢ処理手段は、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_ｉが測点ｉ＝ｎＡ～ｎ１（ただし、ｎ１≦ｎＢ）ごとに、時刻ｔ_ｐ（１）＋Δｔ_Ｂ２で閾値α_σを下回る場合、時刻ｔ_ｐ（１）＋Δｔ_Ｂ２のさらなる時刻後方で、測点ｉ＝ｎＡ～ｎ１（ただし、ｎ１≦ｎＢ）ごとの時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_ｉが閾値α_σを超える時刻をｔ _ｉ として、下式を満足させる測点ｉの時刻ｔ_ｉを選定し、該時刻ｔ_ｉの平均値を時刻平均値ｔ_Ａとし、

上式を満足させる時刻ｔ_ｉがない場合、時刻平均値ｔ_Ａ＝ｔ_{Ｍ１（１）}として、下式でΔｔ_Ａを求め、

分析用２次シース反射Ｍ_１波起生時刻ｔ_{Ｍ１（２）}及び分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）を下式群に基づいて取得するとともに、

下式のｄｓを分析用２次かぶり厚ｄｓ_（２）に、下式のｔ_ｐを前記分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）に置き換えて、分析用２次かぶり厚ｄｓ_（２）を取得し、

前記第３の分析手段、及び前記第４の分析手段における前記分析用１次反射Ｐ波起生時刻ｔ_ｐ（１）を分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）に置き換えて、前記第３の分析手段、及び前記第４の分析手段による再度の分析によって、分析用１次時系列ＧＣ_（１）（ｔ）｜_{ｉ＝１～ｎｗ＋１}の代わりに分析用２次時系列ＧＣ_（２）（ｔ）｜_{ｉ＝１～ｎｗ＋１}を作成し、さらに、前記第５の分析手段による再度の分析で前記分析用２次時系列ＧＣ_（２）（ｔ）｜_{ｉ＝１～ｎｗ＋１}に分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）を用いた前記台形窓関数Ａのｔ_ｐ（２）－Δｔ_ｐ１を始点時刻ｔ_始とし、ｔ_ｐ（２）＋Δｔ_ｐ２を終点時刻ｔ_終とする掃引処理を適用し、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝１～ｎｗ＋１}、及び時刻掃引ｆ_０，ｆ_２スペクトルＳＰ_{ｆ２（２）}（ｆ，ｔ）^ｎｃ｜_{ｉ＝１～ｎｗ＋１}を作成し、次に、ＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}を下式で作成し直すともに、

前記ＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}のＦＦＴ変換でスペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を求め、さらに下式に基づいてスペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を作成し、

前記スペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}の位相情報を、前記スペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}の位相情報に変更したのち、前記スペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}のＦＦＴ逆変換でＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}を作成し、再々度の前記第５の分析手段による前記台形窓関数Ａのｔ_ｐ（２）－Δｔ_ｐ１を始点時刻ｔ_始とし、ｔ_ｐ（２）＋Δｔ_ｐ２を終点時刻ｔ_終とする掃引処理を前記ＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}に適用し、前記分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）とするＳＰ加算の時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝１～ｎｗ＋１}、及び時刻掃引ｆ_０，ｆ_２スペクトルＳＰ_{ｆ２（２）}（ｆ，ｔ）^ｎｃ｜_{ｉ＝ｎｗ＋１}を作成し直したのち、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝ｎＡ～ｎ１}とＳＰ加算の時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝ｎｗ＋１}とを用いて測点ｉ＝ｎＡ～ｎ１各々での、及びＳＰ加算ｉ＝ｎｗ＋１でのグラウト充填状態を、空充判定線分α^～ _σ（＝α_σ＋０．０６）値、及び前記分析用２次かぶり厚ｄｓ_（２）に応じて設定された時刻を＊値とする空充判定カーソルｔ_＊＝ｔ_ｐ（２）＋＊を用いて取得した時刻ｔ_＊での時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ_＊）｜_ｉが、ＳＰ_{ｆ２（２）}（ｔ_＊）｜_ｉ≦α^～ _σの場合に「完全充填」と自動判定し、該判定結果及び時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝１～ｎｗ＋１}を表示部に表示する処理手段であり、前記第８の分析手段の前記第２ＴＢ処理手段は、ｎ１＜ｎＢの場合において、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_{ｉ＝ｎ１＋１～ｎＢ}ごとに時刻ｔ_ｐ（１）－Δｔ_Ｂ１と時刻ｔ_ｐ（１）＋Δｔ_Ｂ２の間で増加傾向にあり、時刻ｔ_ｐ（１）＋Δｔ_Ｂ２で閾値α_σを超える時、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_{ｉ＝ｎ１＋１～ｎＢ}ごとに時刻ｔ_ｐ（１）－Δｔ_Ｂ１と時刻ｔ_ｐ（１）＋Δｔ_Ｂ２との間で閾値α_σを超える時刻をｔ_ｉとし、測点ｉごとの時刻ｔ_ｉの平均値である時刻平均値ｔ_Ａを求め、下式に基づいてΔｔ_Ａを取得するとともに、

下式に基づいて分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）を取得し、

下式のｄｓを分析用２次かぶり厚ｄｓ_（２）に、下式のｔ_ｐを前記分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）に置き換えて、分析用２次かぶり厚ｄｓ_（２）を取得し、

前記第３の分析手段、及び前記第４の分析手段における前記分析用１次反射Ｐ波起生時刻ｔ_ｐ（１）を分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）に置き換えて、前記第３の分析手段、及び前記第４の分析手段による再度の分析によって、分析用１次時系列ＧＣ_（１）（ｔ）｜_{ｉ＝１～ｎｗ＋１}の代わりに分析用２次時系列ＧＣ_（２）（ｔ）｜_{ｉ＝１～ｎｗ＋１}を作成し、さらに、前記第５の分析手段による再度の分析で前記分析用２次時系列ＧＣ_（２）（ｔ）｜_{ｉ＝１～ｎｗ＋１}に分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）を用いた前記台形窓関数Ａのｔ_ｐ（２）－Δｔ_ｐ１を始点時刻ｔ_始とし、ｔ_ｐ（２）＋Δｔ_ｐ２を終点時刻ｔ_終とする掃引処理を適用し、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝１～ｎｗ＋１}、及び時刻掃引ｆ_０，ｆ_２スペクトルＳＰ_{ｆ２（２）}（ｆ，ｔ）^ｎｃ｜_{ｉ＝１～ｎｗ＋１}を作成し、次に、ＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}を下式で作成し直すとともに、

前記ＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}のＦＦＴ変換でスペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を求め、さらに下式に基づいてスペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を作成し、

前記スペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}の位相情報を、スペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}の位相情報に変更したのち、前記スペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}のＦＦＴ逆変換でＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}を作成し、再々度の前記第５の分析手段による前記台形窓関数Ａのｔ_ｐ（２）－Δｔ_ｐ１を始点時刻ｔ_始とし、ｔ_ｐ（２）＋Δｔ_ｐ２を終点時刻ｔ_終とする掃引処理を前記ＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}に適用し、前記分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）とするＳＰ加算の時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝１～ｎｗ＋１}、及び時刻掃引ｆ_０，ｆ_２スペクトルＳＰ_{ｆ２（２）}（ｆ，ｔ）^ｎｃ｜_{ｉ＝ｎｗ＋１}を作成し直したのち、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝ｎ１＋１～ｎＢ}とＳＰ加算の時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝ｎｗ＋１}とを用いて測点ｉ＝ｎ１＋１～ｎＢ各々での、及びＳＰ加算ｉ＝ｎｗ＋１でのグラウト充填状態を、空充判定線分α^～ _σ（＝α_σ＋０．０６）値、及び前記分析用２次かぶり厚ｄｓ_（２）に応じて設定された時刻を＊値とする空充判定カーソルｔ_＊＝ｔ_ｐ（２）＋＊を用いて得る時刻ｔ_＊での時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ_＊）｜_ｉが、α^～ _σ＋０．１８＜ＳＰ_{ｆ２（２）}（ｔ_＊）｜_ｉの場合に「未充填」と自動判定し、α^～ _σ＜ＳＰ_{ｆ２（２）}（ｔ_＊）｜_ｉ≦α^～ _σ＋０．１８の場合に「充填不足」と自動判定し、該判定結果及び時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝１～ｎｗ＋１}を表示部に表示する処理手段であることを特徴とする。
この発明によれば、非破壊検査装置、及びこれを用いた非破壊検査方法は、グラウト充填状態を効率よく、かつ精度よく非破壊検査することができる。 It has a pair of probes consisting of a transmitting probe that transmits ultrasonic waves and a receiving probe that receives ultrasonic waves, and a display unit that displays at least various information, and analyzes the grout filling state of the sheath to be measured. A non-destructive inspection device equipped with an analysis device to determine, and a non-destructive inspection method using the same, wherein the operator operates the concrete longitudinal wave speed, the cover thickness of the second sheath, the plate thickness, and the plate thickness bottom an input receiving means for receiving an input of a path length of a corner; and an imaginary line on the concrete surface along the longitudinal direction of the sheath to be measured passing through the intersection of the concrete surface and a perpendicular line from the cross-sectional center of the sheath to be measured to the concrete surface. Average of the sheath cover thickness at the measurement point i = 1 and the sheath cover thickness at the measurement point i = nw in the multi-point measurement in which the measurement points i = 1 to nw (where nw > 1) are measured in order on the second floor is obtained as the radar- measured cover thickness ds| _RC , and ds in the following equation is replaced with the radar-measured cover thickness ds| _RC to obtain the sheath reflected P-wave occurrence time _tp = _tp | _RC . a recording means of

Ultrasonic waves are continuously transmitted from the transmission probe toward the sheath to be measured at predetermined time intervals, and each time the transmission is performed, the recorded waves obtained by the reception probe are averaged and received at each measurement point i. Wave G(t)| _{i=1 to nw} is obtained, and the received wave G(t)| _{i=1 to nw} is FFT-transformed to obtain the corresponding received wave spectrum F(f)| _{i=1 to nw.} and the second recording means, between the frequency 0.0 and (f _s −Δf _s ) is “0.0”, and between the frequency (f _s −Δf _s ) and f _s is “0.0 to 1.0”, a sinusoidal decreasing function between frequency f _s and (f _s +Δf _s ) is “1.0 to 0.0”, frequency (f _s +Δf _s ) or higher , as the F3 filter function, and the center frequency _fs of the F3(f) filter function is gradually moved to the low frequency side or the high frequency side. , Δt _k is a value set by the operator, "0.0" between time 0.0 and (t _p | _RC -Δt _k ), and "0.0" at time (t _p | _RC -Δt _k ). 0” and becomes “1.0” at time _tp | _RC , and becomes “1.0” at time _tp | _RC and becomes “0.0” at time ( _tp | _RC + _Δtk ) A sin-shaped decreasing function, a function that becomes "0.0" after the time (t _p | _RC + Δt _k ) is defined as a time filter function TGC4(t), and each time the operation receiving means receives an operator's operation, the central vibration For a time-series wave obtained _{by inverse FFT} transforming the spectrum obtained by multiplying the received wave spectrum F(f) | Multiplied by the time filter function TGC4(t) whose central time is the time of occurrence of any measuring point i of the wave, the primary reflection P-wave occurrence time for analysis t _{p (1)} | _{i = 1 to nw} is obtained, and _ds in the following equation is _replaced with the primary cover thickness for analysis ds _{(1 ) |} to acquire the primary cover thickness for analysis ds ₍₁₎ | _i ,

Furthermore, when the primary cover thickness for analysis ds _{(1) |} t _{p (1)} | _i and _the primary cover thickness for analysis ds ( _{1 )} | When the point nB is set to i=nw and the primary cover thickness for analysis ds _{(1) | Occurrence} time _{t p} ( _{1 ) | The primary} cover thickness for analysis ds ₍₁₎ obtained by applying the P-wave occurrence time t _{p(1) |} The primary cover thickness ds ( _{1 )} for analysis obtained by applying _{the next} reflected P-wave occurrence time t p _{( 1)} | a first analysis means for obtaining a start station nA and an end station nB for each primary cover thickness ds ₍₁₎ | _large and ds _{(1) | small} ; f _w is set by the operator to any value within the range of 50 kHz _- Δf _w < f _w < 50 kHz + _{Δf w} (however, Δf _w = 5 kHz). A sine-shaped increasing function from "0.0 to 1.0", a sine-shaped decreasing function from " _1.0 to 0.0" from frequency f0 to _fw , and from frequency _fw to _f2 "0 .0 to 1.0", sinusoidal decreasing function from frequency _f2 to ( _f2 +30kHz) from "1.0 to 0.0", frequency ( _f2 +30kHz) and above A _received wave spectrum _F (f) | Spectra for analysis FA(f)| _{i=1 to nw+1} are obtained, and the spectrums for analysis FA(f)| _{i=1 to nw+1} are inversely transformed by FFT to obtain corresponding time series GA(t)| _i= for analysis. _{1 to nw+1} and the primary cover thickness for analysis ds _{(1) |} With the raw time t _{p(1) | i} as t _{p(1) and} the primary cover thickness for analysis ds ₍₁₎ | 5 analysis means, a sixth analysis means, a seventh analysis means, and a first processing means for determining the grout filling state of the sheath to be measured by analysis by the analysis means, i = 1 to nw _When the analytical primary cover _thickness ds _{( 1 )} | the _third analysis means, the fourth analysis means, the fifth analysis _means , _the sixth analysis means, the seventh and the analysis by the eighth analysis means, the second processing means for determining the grout filling state of the measurement target sheath at _{the large} primary cover thickness ds ₍₁₎ | for analysis; , the analysis primary reflected P-wave occurrence time _tp(1) is set to _tp(1) | _small , and the analysis primary cover thickness ds ₍₁₎ is set to ds _{( 1)} By the third analysis means, the fourth analysis means, the fifth analysis means, the sixth analysis means, the seventh analysis means, and the eighth analysis means replaced with | _small a third processing means for determining the grout filling state of the measurement target sheath at _{the small} primary cover thickness for analysis ds _{( 1)} | ₎ The time filter function TGC1(t) with +Δt _h1 as the reference time and the time filter function TGC2(t) with the time _tp(1) as the reference time are obtained from the analysis time series GA(t)| _{i=1 ~ nw + 1} to obtain the cutout wave for analysis GB ₍₁₎ (t) | _{i = 1 to nw + 1 ,} and the cutout wave for analysis GB ₍₁₎ (t) | _spectrum FB _{(1) ( f} ) _| Using a sine-shaped increasing line segment that becomes “0.0” at 0 and becomes “1.0” at the reference time _t , and a TGCA(t) function that becomes “1.0” after the time t = the reference time _t is a function calculated by (TGCA(t)) ^ne , and the time filter function TGC2(t) is calculated from time _t = _0.0 to time t=t _h is "1.0", time t = reference time t becomes "1.0" at time t = 400 µs and becomes "0.0 _" at time t = 400 µs. 0.0" using the TGCB(t) function, (TGCB(t)) is a function calculated by ^nf , and the fourth analysis means calculates the spectrum FB ₍₁₎ (f)| _{i= 1 to nw+1} , after setting the maximum spectral value on the lower frequency side than the frequency _fw for each i to the reference value = 1.0, the maximum spectral value on the higher frequency side than the frequency _fw Obtain _the primary _spectrum for _analysis FC _{(1) (} f) | ( _{1 )} (t) _| = t _{p (1)} - Δt _p1 to _{the end} of time t = t _{p (1)} + Δt _p2 every time it is moved at intervals of Δt _a , the primary time series for analysis GC ₍₁₎ (t) _| A spectrum corresponding to the time series cut out by multiplying _nw+1 by a trapezoidal window function A is obtained, and in the spectrum obtained by normalizing the maximum spectrum value at the frequency fw _or less to 1.0, the frequency fw _or more Time sweep normalized _spectral value SP _{f2 (1)} ( _t ) | Time sweep f _{0 ,} f ₂ spectrum SP _{f 2 (1)} (f _{, t )} ^nc _{| _ Alternatively} , if t _a is the value indicating the time width set _according to ds _{(1) |} sine-shaped increasing function from t _start to "0.0" to "1.0", time t = t _start to t _start + _ta is "1.0", time t = t _start + t _a to t _start + t A sin-shaped decreasing function where _a +5 is "1.0" to "0.0", and a function where time t = t _start + t _a +5 and later are "0.0", and the sixth analysis means is Using the start measurement point nA and the end measurement point nB obtained by the first analysis means, the time sweep normalized spectrum value SP _{f2 (1)} (t)| _i=nA~nB spectrum value at the station i=nA~n1 (where boundary station n1 ≤ end station nB), from time t _p(1) -Δt _B1 to time Characteristic TA, or time sweep criterion, by which said boundary station n1 is identified with an increasing trend between t _{p (1)} +Δt _B2 and confirming that the threshold α _σ is exceeded at time t p(1) +Δt _B2 spectral value SP _{f2(1) (} t ₎ | +Δt _B2 is less than the threshold value α _σ to identify which characteristic TB the boundary survey point n1 is identified, and the seventh analysis means performs the sixth analysis In the means, when the spectrum shape of _{i=nA to nB} is identified as the characteristic TA, the time sweep normalized spectral value SP _{f2(1) (} t)| Based on _{i = nA to nB} , analysis is performed by the first TA processing means and the second TA processing means, and the analysis means determines the grout filling state, and the eighth analysis means is the sixth analysis means. , time _- swept normalized spectral values SP _{f2( 1)} (t) _| Based on _{nA to nB} , the analysis is performed by the first TB processing means and the second TB processing means, and the analysis means determines the grout filling state, and the first TA processing means of the seventh analysis means is based on the time sweep reference. spectral _value SP _{f2(1) ( t ) |} When the threshold value α _σ is exceeded at time t _p(1) +Δt _B2 , the time sweep normalized spectrum value SP _f2(1) (t) | _{i=nA to n1} (where n1≦ nB), between the time t _p(1) −Δt _B1 and the time t _p(1) +Δt _B2 , let t _i be the time when the threshold value _ασ is exceeded, and let t _A be the average value. Obtaining Δt _A based on the formula,

Acquire the analysis secondary reflection P-wave occurrence time t _{p (2)} based on the following formula,

ds in the following equation is replaced by the secondary cover thickness ds ₍₂₎ for analysis, and _tp in the following equation is replaced by the secondary reflection P-wave occurrence time _tp(2) for analysis, and the secondary cover thickness ds _{( 2)} to obtain

By replacing the analysis primary reflected P-wave occurrence time _tp(1) in the third analysis means and the fourth analysis means with the analysis secondary reflection P-wave occurrence time _tp(2) , the third analysis means, and the second analysis by the fourth analysis means, the analysis primary time series GC ₍₁₎ (t) | _{i = 1 to nw + 1} instead of the analysis secondary time series GC _{(2 )} ( _t ) _| Let t _p(2) −Δt _p1 of the trapezoidal window function A using the analysis secondary reflection P-wave occurrence time _{t p(2)} be the _start point time t, and t _p(2) +Δt _p2 be the end point time t _{apply the} time-swept normalized _spectrum values SP _{f2( 2 )} ⁽ t)| Create | _{i = 1 to nw + 1} , then recreate WAVE addition average wave GC ₍₂₎ (t) | _{i = nw + 1} with the following formula,

The spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 , and the ^spectrum FC ₍₂₎ (f) Create | _i=nw+1 ,

After changing the phase information of the spectrum ^FC ₍₂₎ (f)| _i=nw+1 to the phase information of the spectrum FC ₍₂₎ (f)| _i=nw+1 , the ^spectrum FC ₍₂₎ (f) | _{i = nw + 1 FFT} inverse transform to create SP addition average wave GC ^~ ₍₂₎ (t ₎ | -Δt _p1 is the _start point time t and t _{p (2) +} Δt _p2 is applied to the SP addition average wave GC ^~ ₍₂₎ ( _t ) | Time sweep normalized _spectrum value SP _{f2( 2 )} ( _t ) | After recreating _f2(2) (f, t) ^nc | _{i=nw+1 ,} time sweep normalized spectrum value SP _f2(2) (t)| Using _the value SP _{f2 (2) (} ^t )| =α _σ +0.06) value and the time set according to the secondary cover _thickness ds _{( 2)} for analysis. The acquired time-swept normalized spectral _value SP _{f2(2) (} t _{* )} ^| _i at time t _* is _“ unfilled ” ^, and when α ^~ _σ < SP _{f2 (2) (} t _* ) _| SP _f2(2) ( _t )| When the spectral value SP _f2(1) (t)| _i falls below the threshold α _σ at time t _p(1) +Δt _B2 for each station i=n1+1 to nB, further times at time t _p(1) +Δt _B2 At the rear, the time sweep normalized spectral value SP _{f2(1) ( t} ) _{| i} is selected, the average value of the time t _i is the time average value t _A ,

If there is no time t _i that satisfies the above formula, the time average value t _A = t _{M1 (1)} , and Δt _A is obtained by the following formula,

Obtaining the analysis secondary sheath reflection M ₁ wave occurrence time t _M1(2) and the analysis secondary reflection P wave occurrence time t _p(2) based on the following equation group,

Substituting ds in the following equation for the secondary cover thickness ds ₍₂₎ for analysis, and replacing _tp in the following equation for the secondary reflection P-wave occurrence time _tp(2) for analysis, the secondary cover thickness ds for analysis ₍₂₎ is obtained,

By replacing the analysis primary reflected P-wave occurrence time _tp(1) in the third analysis means and the fourth analysis means with the analysis secondary reflection P-wave occurrence time _tp(2) , the third analysis means, and the second analysis by the fourth analysis means, the analysis primary time series GC ₍₁₎ (t) | _{i = 1 to nw + 1} instead of the analysis secondary time series GC _{(2 )} ( _t ) _| Let t _p(2) −Δt _p1 of the trapezoidal window function A using the analysis secondary reflection P-wave occurrence time _{t p(2)} be the _start point time t, and t _p(2) +Δt _p2 be the end point time t _{apply the} time-swept normalized _spectrum values SP _{f2( 2 )} ⁽ t)| Create | _{i = 1 to nw + 1} , then recreate WAVE addition average wave GC ₍₂₎ (t) | _{i = nw + 1} with the following formula,

The spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 , and the ^spectrum FC ₍₂₎ (f) Create | _i=nw+1 ,

After changing the phase information of the spectrum ^FC ₍₂₎ (f)| _i=nw+1 to the phase information of the spectrum FC ₍₂₎ (f)| _i=nw+1 , the ^spectrum FC ₍₂₎ (f) | _{i = nw + 1 FFT} inverse transform to create SP addition average wave GC ^~ ₍₂₎ (t ₎ | -Δt _p1 is the _start point time t and t _{p (2) +} Δt _p2 is applied to the SP addition average wave GC ^~ ₍₂₎ ( _t ) | Time _- swept normalized _spectrum value SP _{f2(2) ( t} ) | After recreating SP _{f2(2 ) (} f, _t ) ^nc | Spectral _value SP _{f2 (2)} ⁽ _t ) | (=α _σ +0.06) and the time set according to the secondary cover thickness ds ( _{2 )} for analysis is used as the _* value. _The time-swept normalized spectral value SP _{f2(2) ( t * )} ^| _i at time t _* obtained by processing means for automatically determining and displaying the determination result and the time-swept standardized spectral values SP _{f2(2) (} t)| The means is that the time _- swept normalized spectrum value _{SP f2(1) ( t} ) | If less, at a further time after time t _p(1) +Δt _B2 , the time-swept normalized spectral value SP _f2(1) (t)| _i for each station i=nA to n1 (where n1≦nB) Let the time t i exceed the threshold value α _σ , select the time _{t i at} the measurement point i that satisfies the following equation, and set the average value of the time t _i as the time average value t _A ,

If there is no time t _i that satisfies the above formula, the time average value t _A = t _{M1 (1)} , and Δt _A is obtained by the following formula,

Obtaining the analysis secondary sheath reflection M ₁ wave occurrence time t _M1(2) and the analysis secondary reflection P wave occurrence time t _p(2) based on the following equation group,

Substituting ds in the following equation for the secondary cover thickness ds ₍₂₎ for analysis, and replacing _tp in the following equation for the secondary reflection P-wave occurrence time _tp(2) for analysis, the secondary cover thickness ds for analysis ₍₂₎ is obtained,

By replacing the analysis primary reflected P-wave occurrence time _tp(1) in the third analysis means and the fourth analysis means with the analysis secondary reflection P-wave occurrence time _tp(2) , the third analysis means, and the second analysis by the fourth analysis means, the analysis primary time series GC ₍₁₎ (t) | _{i = 1 to nw + 1} instead of the analysis secondary time series GC _{(2 )} ( _t ) _| Let t _p(2) −Δt _p1 of the trapezoidal window function A using the analysis secondary reflection P-wave occurrence time _{t p(2)} be the _start point time t, and t _p(2) +Δt _p2 be the end point time t _{apply the} time-swept normalized _spectrum values SP _{f2( 2 )} ⁽ t)| Create | _{i = 1 to nw + 1} , then recreate WAVE addition average wave GC ₍₂₎ (t) | _{i = nw + 1} with the following formula,

The spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 , and the ^spectrum FC ₍₂₎ (f) Create | _i=nw+1 ,

After changing the phase information of the spectrum ^FC ₍₂₎ (f)| _i=nw+1 to the phase information of the spectrum FC ₍₂₎ (f)| _i=nw+1 , the ^spectrum FC ₍₂₎ (f) | _{i = nw + 1 FFT} inverse transform to create SP addition average wave GC ^~ ₍₂₎ (t ₎ | -Δt _p1 is the _start point time t and t _{p (2) +} Δt _p2 is applied to the SP addition average wave GC ^~ ₍₂₎ ( _t ) | Time sweep normalized _spectrum value SP _{f2( 2 )} ( _t ) | After recreating _f2(2) (f, t) ^nc | _{i=nw+1 ,} time sweep normalized spectrum value SP _f2(2) (t)| Using _the value SP _{f2 (2) (} ^t )| =α _σ +0.06) value and the time set according to the secondary cover _thickness ds _{( 2)} for analysis. The acquired time-swept normalized spectral _value SP _f2(2) (t _* )| _i at time t _* is automatically labeled as “ ^fully filled” if SP _f2(2) (t _{* )} | and displaying the determination result and the time-swept standardized spectral values SP _f2(2) (t)| _{i=1 to nw+1} on a display unit, wherein _is the time sweep normalized spectrum value SP _{f2(1) ( t ) |} When the threshold α _σ is exceeded at time t _{p (1)} + Δt _B2 , the time sweep normalized spectrum value SP _{f2 (1)} (t) | _{i = n1 + 1} to time t _{p (1 )} The time between −Δt _B1 and time t _p(1) +Δt _B2 when the threshold value α _σ is exceeded is t _i , and the time average value t _A that is the average value of the time _t i for each measurement point i is obtained. Obtaining Δt _A based on the formula,

Acquire the analysis secondary reflection P-wave occurrence time t _{p (2)} based on the following formula,

Substituting ds in the following equation for the secondary cover thickness ds ₍₂₎ for analysis, and replacing _tp in the following equation for the secondary reflection P-wave occurrence time _tp(2) for analysis, the secondary cover thickness ds for analysis ₍₂₎ is obtained,

By replacing the analysis primary reflected P-wave occurrence time _tp(1) in the third analysis means and the fourth analysis means with the analysis secondary reflection P-wave occurrence time _tp(2) , the third analysis means, and the second analysis by the fourth analysis means, the analysis primary time series GC ₍₁₎ (t) | _{i = 1 to nw + 1} instead of the analysis secondary time series GC _{(2 )} ( _t ) _| Let t _p(2) −Δt _p1 of the trapezoidal window function A using the analysis secondary reflection P-wave occurrence time _{t p(2)} be the _start point time t, and t _p(2) +Δt _p2 be the end point time t _{apply the} time-swept normalized _spectrum values SP _{f2( 2 )} ⁽ t)| Create | _{i = 1 to nw + 1} , then recreate WAVE addition average wave GC ₍₂₎ (t) | _{i = nw + 1} with the following formula,

The spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 , and the ^spectrum FC ₍₂₎ (f) Create | _i=nw+1 ,

After changing the phase information of the spectrum ^FC ₍₂₎ (f)| _i=nw+1 to the phase information of the spectrum FC ₍₂₎ (f)| _i=nw+1 , the spectrum ^FC ₍₂₎ (f)| SP addition average wave GC ^~ ( _{2 ) (} t ₎ | A sweep process with Δt _p1 as the _start point time t and t _{p (2)} + Δt _p2 as the _end point time t is applied to the SP addition average wave GC ^~ ₍₂₎ ( _t ) | Time _sweep normalized _{spectrum value} SP _{f2(2) ( t} ) | ₍₂₎ After recreating (f, t) ^nc | _i=nw+1 , the time sweep normalized spectrum value SP _f2(2) (t) | _{i=n1+1 to nB} and the time sweep normalized spectrum value of SP addition SP f2 _{( 2)} ( _t ) ^| α _σ +0.06) value and the time set according to the secondary cover thickness ds ₍₂₎ for analysis is obtained using an empty determination cursor t _* = t _{p (2)} + * Time-swept normalized spectral value SP _f2(2) (t _{* )} | _i at time t* is “unfilled” if α ^~ _σ + 0.18 < SP _f2(2) (t _* )| _i Automatically ^determine , _and when α ^~ _σ < SP _{f2 (2) ( t *} ) | ₍₂₎ It is a processing means for displaying (t)| _{i=1 to nw+1} on a display unit.
ADVANTAGE OF THE INVENTION According to this invention, the nondestructive inspection apparatus and the nondestructive inspection method using the same can carry out the nondestructive inspection of the grout filling state efficiently and accurately.

As an aspect of the present invention, the second analysis means replaces the A _K (f) filter function with an A _G (f) ^nG filter function, and the analysis spectrum FA ( f) means for obtaining | _i and _the analysis time series GA(t)| _i , wherein the A _{G (} f ^{) nG} filter function is (f _w ⁺ f = 80 kHz) is a frequency f _k , a sine-shaped increasing function that becomes “ _0.0 ” at the frequency f = 0.0 and “1.0” at the frequency f _k , and “1 .0”, a sin-shaped decreasing function that becomes “0.0” at the frequency f _k ×2, and a function that becomes “0.0” at the frequency f _k ×2 or more, and the A _G ( f) The nG value of ^{the nG} filter function is any value in the range of 40 kHz - _{Δf w <} f _w < 40 kHz + Δf _w (where Δf _w = 5 kHz) set by the operator's operation, The analysis spectrum FA(f) | _i is a value when the maximum spectrum value occurs between the frequency f _w ~ frequency _f ⁼ 80 kHz at any of the measurement points i, and the fourth analysis The means normalizes the maximum spectrum value at the frequency fw _or less for each spectrum FB(f) _{| i=1 to nw+1} acquired by the third analysis means to 1.0, is means for setting the maximum spectral value at the threshold value α _σ , and the fifth analysis means includes the time-swept standardized spectral value SP _f2(1) (t)| _{i=1 to nw+1} and the time-swept Instead of the f ₀ , f ₂ spectrum SP _{f2 (1} ) (f, _t ) ^nc _| , and a time sweep f ₀ , (f ₁ to f ₂ ) spectrum SP _f1,2(1) (f, _t ) ^nc | Time-swept normalized spectral values SP _f1,2(1) ( _t )| The seventh analysis means and the eighth analysis means are means for specifying, the time sweep normalized spectrum value SP _f2(2) (t)| _i and the time sweep f ₀ , f ₂ spectrum Instead of SP _f2(2) (f _, t) ^nc | _i , time-swept normalized _spectral values SP _{f1,2(2) ( t} )| Create _a spectrum SP f1,2( _{2 )} (f _, t ₎ ^nc _| It may be a means for determining the grout filling condition by determining the time-swept normalized spectral values SP _f1,2(2) (t _* )| _i at t _* .
According to this configuration, the nondestructive inspection device and the nondestructive inspection method can more efficiently and accurately nondestructively inspect the filled state of grout.

ADVANTAGE OF THE INVENTION By this invention, the nondestructive inspection apparatus which can nondestructively inspect a grout filling state efficiently and accurately, and a nondestructive inspection method can be provided.

Schematic diagram for explaining the outline of sheath reflected wave measurement. Explanatory drawing explaining the relationship between the frequency of a sheath reflected wave occurrence time band, and a spectrum value. FIG. 4 is an explanatory diagram for explaining an outline of a sheath reflected wave mixed with a residual wave; Explanatory drawing explaining the outline of the wave which arises by the vibration behavior of an empty sheath. Explanatory drawing explaining the outline of the generation|occurrence|production situation of a vibration behavioral wave. Explanatory drawing explaining the outline of the received wave which arises by the difference in the measurement position in an existing bridge. FIG. 4 is an explanatory diagram for explaining an outline of spectral waveform conversion processing using threshold values _ασ ; The block diagram which shows the structure of a nondestructive inspection apparatus. Explanatory drawing explaining a grout filling state. The block diagram which shows the internal structure of a nondestructive inspection apparatus. The schematic diagram which shows the outline of the ultrasonic wave which propagates the inside of concrete. The schematic diagram which shows the outline of the ultrasonic wave which propagates the inside of concrete. Schematic diagram showing an outline of multi-point measurement. Explanatory drawing explaining the outline of a threshold-value analysis process. Explanatory drawing explaining the outline of a threshold-value analysis process. Explanatory drawing explaining the outline of a threshold-value analysis process. Explanatory drawing explaining the outline of a threshold-value analysis process. Explanatory drawing explaining the outline of a threshold-value analysis process. Explanatory drawing explaining the outline of a threshold-value analysis process. Explanatory drawing explaining the outline of a threshold-value analysis process. Explanatory drawing explaining the outline of a threshold-value analysis process. 4 is a flowchart showing the operation of reflected P-wave automated analysis processing; 4 is a flowchart showing the operation of the first process; 4 is a flowchart showing the operation of the first process; Schematic diagram showing the outline of the measurement situation of the girder beam and the edge of the side wall. Explanatory drawing explaining the outline of a reflected P-wave automatic analysis process. FIG. 4 is an explanatory diagram for explaining a primary cover thickness pattern for analysis; Explanatory drawing explaining the outline in the analysis example 1. FIG. Explanatory drawing explaining the outline in the analysis example 1. FIG. Explanatory drawing explaining the outline in the analysis example 1. FIG. Explanatory drawing explaining the outline in the analysis example 1. FIG. Explanatory drawing explaining the outline in the analysis example 2. FIG. Explanatory drawing explaining the outline in the analysis example 2. FIG. Explanatory drawing explaining the outline in the analysis example 2. FIG. Explanatory drawing explaining the outline in the analysis example 3. FIG. Explanatory drawing explaining the outline in the analysis example 3. FIG. Explanatory drawing explaining the outline in the analysis example 3. FIG. Explanatory drawing explaining the outline in the analysis example 4. FIG. Explanatory drawing explaining the outline in the analysis example 4. FIG. Explanatory drawing explaining the verification of the correctness of the threshold-reflection P-wave analysis method. Explanatory drawing explaining the verification of the correctness of the threshold-reflection P-wave analysis method. Explanatory drawing for explaining the occurrence of sheath reflection P wave, sheath reflection _M1 wave, and sheath reflection _M2 wave depending on the size of center-to-center distance a/straight line distance d. FIG. 4 is an explanatory diagram for explaining an outline of an optimum probe interval for reflected P-wave measurement; Explanatory drawing explaining reflection P wave measurement probe arrangement|positioning of a girder and a box girder edge. Explanatory drawing explaining the _AK (f) filter function and _AG (f) ^nG filter function. _AG (f) Explanatory diagram explaining the outline of the threshold reflection P-wave automated analysis using the ^nG filter function. _AG (f) Explanatory drawing explaining the analysis using ^nG filter function. _AG (f) Explanatory drawing explaining the analysis using ^nG filter function. Explanatory drawing explaining the grout filling state investigation measurement position of a box-girder PC bridge.

An embodiment of the invention will be described below with reference to the drawings.
<Physical phenomenon used in the present invention>
First, spectral characteristics of received ultrasonic waves in non-destructive inspection of grout filling state will be described.

Ultrasonic waves have the property of being reflected at the interfaces of substances with different acoustic impedances. Acoustic impedance expresses the resistance value when ultrasonic waves propagate through a substance. The higher the acoustic impedance, the lower the resistance value, and conversely, the lower the acoustic impedance, the higher the resistance value.

Since the acoustic impedance of air is extremely low, if there is a cavity, ultrasonic waves are almost totally reflected in the cavity, generating a reflected wave with a large amplitude. On the other hand, since the reflectance of ultrasonic waves is low when the material is solid, a reflected wave with a small amplitude is generated.

As shown in Fig. 1, in sheath reflected wave measurement in which a transmitting probe and a receiving probe are placed on a concrete plane directly above the sheath pipe, when ultrasonic waves are input from the transmitting probe to the concrete surface, ultrasonic waves follows roughly three propagation paths to reach the receiving probe.

As shown in FIGS. 1(a) and 1(b), the received waves received by this receiving probe are direct waves (DI waves) that are transmitted so as to bypass the inside of the concrete, and waves that are naturally generated on the concrete surface. surface waves (surface _P1 wave, which is a longitudinal wave, and surface _S1 wave, which is a transverse wave) and sheath reflected waves that return after being reflected by the sheath tube. These waves have different properties due to different propagation paths.

A direct wave (DI wave) and a surface wave (surface _P1 wave, surface _S1 wave) are predominantly ultrasonic waves in a low vibration band with low directivity. On the other hand, sheath-reflected waves are predominantly high-frequency waves with high directivity.
There are multiple frequencies where the sheath reflected wave is large and dominant. In the spectrum, the high frequency side is large when the grout is not filled, and the low frequency side is large when the grout is completely filled. there is Utilizing this phenomenon is one of the basics of the present invention.

FIG. 2(a) shows the surface P ₁ wave, surface S ₁ wave, 1 is a spectrum conceptual diagram of a rear residual wave of a direct wave (DI wave) and a composite wave residual spectrum. FIG. Note that the central frequency _f0 is approximately 20 kHz.

FIG. 2(b) is a conceptual diagram of the spectrum of the sheath reflected wave in the sheath reflected wave generation time band, showing the high frequency (f ₁ , f ₂ ) band spectrum in the large-diameter sheath tube. Furthermore, the solid line in FIG. 2(b) indicates the case where the grout filling state is unfilled, and the broken line in FIG. 2(b) indicates the case where the grout filling state is the filled state.
In FIG. 2, the maximum spectrum value at the center frequency f ₀ is set to the reference value "1.0", and the spectrum value for each frequency is shown by replacing it with a relative value with respect to the reference value "1.0". .

In general, in existing PC bridge concrete (concrete longitudinal wave sound velocity = around 4300 m/sec), many measurement examples show that the frequency _f1 exceeds 40 kHz and the frequency _f2 is 60 to 80 kHz. Confirmed. The frequency f ₁ and the frequency f ₂ move to the high frequency side as the concrete strength (concrete longitudinal wave sound velocity) increases, and move to the low frequency side as the concrete strength decreases.

Since the surface P ₁ wave, the surface S ₁ wave, and the backward residual wave of the direct wave (DI wave) in FIG. 1 are mixed on the sheath reflected P wave, the spectrum of the sheath reflected wave occurrence time band is shown in FIG. As shown in (a), if the phase information is neglected, the conceptual diagram of the spectrum is obtained by adding the diagrams of FIGS. 2(a) and 2(b).

In the spectrum conceptual diagram of FIG. 3( a ), the spectrum values at the frequency f ₀ of the surface P ₁ wave, the surface S ₁ wave, and the surface wave (DI wave) are For example, it can be considered that the grout filling state is almost the same regardless of whether it is unfilled or completely filled.
FIG. 3(b) shows a spectrum conceptual diagram of the generation time band of sheath-reflected P-waves in the case of a small-diameter sheath tube.

As the diameter of the sheath tube becomes smaller, the reflection amplitude becomes smaller, so that the spectral values of the frequencies f ₁ and f ₂ become smaller. For this reason, the difference in magnitude of the spectral value between the unfilled grout state and the complete grout filling state is also small.

Actually, reflected waves reflected by reflection sources other than the sheath pipe, such as reinforcing bars, fine cracks, adjacent sheath pipes, and surface reflected waves from the edge of the concrete surface, are mixed into the sheath reflected P wave.
Furthermore, a wave with a large amplitude (hereinafter referred to as an interfering wave) such as a reflected wave from the second sheath, the thickness of the WEB, and the corner of the bottom surface of the WEB is mixed behind the sheath reflected P wave.

Therefore, in the case of a small-diameter sheath pipe, only the magnitude relationship of the spectrum of the frequency _f1 and the frequency _f2 in FIG. It becomes extremely difficult.

By the way, the applicant believes that when the grouting state is unfilled, the sheath pipe behaves in self-excited vibration due to the input P wave or the input S wave input to the sheath pipe, and the frequency f ₁ and the frequency f ₂ spectrum is as shown in FIG. 4(a).

Even with a small-diameter sheath tube, the spectrum shape in the time band of the sheath-reflected wave is a superimposition of FIG. 3(b) and FIG. This is a comparison chart. In the case of the sheath pipe in which the grouting state is unfilled, the spectral values at the frequency f ₁ and the frequency f ₂ become larger than those of the sheath pipe in which the grouting state is completely filled.

In the sheath pipe in which the grouting state shown in FIG. different. Immediately after placing concrete, the concrete around the sheath pipe and the sheath pipe are in close contact with each other at the boundary. Furthermore, since the actual bridge constantly exhibits vibrational behavior due to the running of the vehicle, the degree of this change increases.

Therefore, as shown in FIG. 5, the vibration of the vibration behavior wave in the sheath pipe that is not filled with grout should be small at the time of placing concrete and increase with time. The phenomenon that the spectral value of the vibration behavior in the unfilled sheath tube increases as shown in FIG. 4 is a convenient phenomenon for confirming the grout filling state in the case of an existing PC bridge.

<Basic analysis of the present invention>
FIG. 6 shows a schematic diagram of the received wave spectrum of the sheath tube in the existing PC bridge. 6(a), 6(b), 6(c), and 6(d) are schematic diagrams of spectrums of received waves at measurement points separated in the longitudinal direction of the sheath tube directly above the sheath tube. are shown respectively.
In FIG. 6, the maximum spectrum value on the lower frequency side than the frequency _fw is set to the reference value "1.0", and the spectrum value for each frequency is replaced with a relative value with respect to the reference value "1.0". ing. It should be noted that replacing the spectral value for each frequency or time with a relative value to the reference value "1.0" with the maximum spectrum value as the reference value "1.0" is hereinafter referred to as "normalization".

In the spectrum of the received wave, the spectral value on the higher frequency side than the frequency _fw may be extremely large or small. Originally, the spectral shape of the received wave spectrum should be approximately the same for each measurement point, but this is not the case.

Many existing PC bridges are 40 to 60 years old, and there are cases where the concrete surface of the girders and box girders is uneven, and the concrete surface and the inside of the concrete are extremely deteriorated. There is also
Furthermore, in existing PC bridges, the arrangement of the reinforcing bars embedded in the concrete surface layer is uneven, and the intervals between the reinforcing bars may be narrow or wide.
In addition, existing PC bridges may have many cracks that block the propagation of ultrasonic waves on the surface of the concrete, or fine turtle-like cracks that are difficult to see.

Furthermore, when the concrete surface layer is deteriorated, when the transmitting probe and the receiving probe are placed on the concrete surface, a large amount of ultrasonic wave transmission medium is applied to the concrete surface, but the concrete surface is deteriorated in a short time. By penetrating inside, the characteristics of the received ultrasonic waves change greatly.
In this way, the phenomenon shown in FIG. 6 is caused by a combination of various reasons. Dealing with this problem is one of the foundations of the analysis in the present invention.

Therefore, the threshold value _{ασ of} the spectrum value is set, and in the normalized display spectrum shown in _FIG . ), the spectrum obtained by amplifying the maximum spectral value ε to the threshold α _σ is used for the analysis of the grout filling state, and if the maximum spectral value ε is greater than the threshold α _σ , FIG. As shown in , the spectrum obtained by attenuating the maximum spectral value ε to the threshold value α _σ is used for the analysis of the grout filling state.

<Nondestructive Inspection Apparatus and Nondestructive Inspection Method Based on Sheath Reflection P-Wave Threshold Analysis of the Present Embodiment>
Next, a sheath-reflected P-wave nondestructive inspection apparatus using ultrasonic waves and a sheath-reflected P-wave nondestructive inspection method using this apparatus according to the present embodiment will be described.
The non-destructive inspection apparatus 10 of this embodiment is a concrete structure such as a main girder, a cross girder, a box girder, and a bottom slab of a bridge as shown in FIG. 49 manufactured by the post tension construction method. This is a non-destructive inspection of the grout filling state of the embedded sheath pipe 2 . Such a nondestructive inspection apparatus 10 will be described with reference to FIGS. 8 to 13. FIG.

8 shows a configuration diagram of the nondestructive inspection apparatus 10, FIG. 9 shows an explanatory diagram explaining the grout filling state, FIG. 10 shows a block diagram of the nondestructive inspection apparatus 10, and FIGS. A schematic diagram of ultrasonic waves propagating inside concrete 4 is shown, and FIG. 13 shows a schematic diagram of multi-point measurement.

Furthermore, FIG. 9(a) shows a cross-sectional view of the sheath tube 2 when the grouting state is completely filled, and FIG. 9(b) shows a cross-sectional view of the sheath tube 2 when the grouting state is insufficiently filled, FIG. 9(c) shows a cross-sectional view of the sheath tube 2 when the grout is not yet filled.

First, a prestressed concrete structure 1, which is an object to be inspected, will be described.
As shown in FIGS. 8 and 9A, the prestressed concrete structure 1 includes a substantially cylindrical sheath pipe 2, a PC steel material 3 disposed inside the sheath pipe 2, and a Concrete 4 that has been placed.
The PC steel material 3 is formed by kneading together a plurality of steel wires 3a, as shown in FIG. 9(a).

This prestressed concrete structure 1 is constructed by arranging the sheath pipe 2 at a predetermined position in the formwork and then before pouring the concrete 4 into the formwork or after pouring the concrete 4 into the formwork. A PC steel material 3 is inserted in 2 .

After the curing period of the concrete has passed, the sheath pipe 2 containing the PC steel material 3 tensioned with a predetermined tension is fixed to the concrete 4 and formed. As a result, the prestressed concrete structure 1 generates compressive stress along the longitudinal direction of the sheath pipe 2 inside the concrete 4 .

Further, the interior of the sheath tube 2 is filled with grout 5 such as cement milk to prevent the PC steel material 3 from rusting, as shown in FIG. 9(a). As shown in FIG. 9(a), the grout filling state in which the inside of the sheath tube 2 is filled with the grout 5 without gaps is referred to as complete filling. The sheath tube 2 in which the grout is completely filled is referred to as a filled sheath.

Moreover, as another aspect of the grout filling state, as shown in FIG. Set the status to underfilled.
Further, as shown in FIG. 9(c), the grout-filled state in which the inside of the sheath tube 2 is not filled with the grout 5 is defined as unfilled. In addition, the sheath pipe 2 that is not yet filled with grout is referred to as an empty sheath.

The nondestructive inspection apparatus 10 in this embodiment is an apparatus that nondestructively inspects the grouting state of the sheath tube 2 to be measured.
As shown in FIGS. 8 and 10, the nondestructive inspection apparatus 10 includes a surface transmitting unit 11 and a surface receiving unit 12 which are arranged on the concrete upper surface 4a of the prestressed concrete structure 1, a surface transmitting unit 11, and a surface transmitting unit 11. It is composed of an analysis device 13 electrically connected to a surface receiving unit 12 .

The surface transmission unit 11 is arranged on the concrete upper surface 4a positioned directly above the sheath tube 2, as shown in FIG. As shown in FIG. 8, the surface transmission unit 11 has a bottom surface in contact with the concrete top surface 4a, which is configured as a transmission probe 11a for transmitting ultrasonic waves.

The surface transmission unit 11 has a function of receiving an ultrasonic transmission signal from the analysis device 13, and based on the ultrasonic transmission signal, the transmission probe 11a emits an ultrasonic wave E from the upper surface 4a of the concrete to the inside of the prestressed concrete structure 1. (See FIG. 13).

As shown in FIG. 8, the surface receiving unit 12 is separated from the surface transmitting unit 11 in the longitudinal direction of the sheath tube 2 to be measured, and is arranged on the concrete upper surface 4a positioned directly above the sheath tube 2 . As shown in FIG. 8, the surface receiving unit 12 has a bottom surface in contact with the concrete top surface 4a, which serves as a receiving probe 12a for receiving ultrasonic waves.

Then, the surface receiving unit 12 has a function of receiving the ultrasonic wave E propagated inside the prestressed concrete structure 1 as an incident wave R (see FIG. 13) by the receiving probe 12a, and a receiving function indicating the received incident wave R. and a function of transmitting the signal to the analysis device 13 .

As shown in FIG. 10, the analysis device 13 includes a transmission unit connection section 131 to which the surface transmission unit 11 is connected, a reception unit connection section 132 to which the surface reception unit 12 is connected, and a storage section 133 for storing various information. , an operation unit 134 for receiving an operator's operation, a display unit 135 for displaying various information, and a control unit 136 for controlling these.
Note that the analysis device 13 implements a first recording process, a second recording process, a first analysis process, a second analysis process, a first process, a second process, and a third process, which will be described later. It is configured as a means to

The transmission unit connection section 131 has a function of outputting an ultrasonic transmission signal to the surface transmission unit 11 according to an instruction from the control section 136 .
The reception unit connection section 132 has a function of receiving a reception signal from the surface reception unit 12 and a function of transmitting the reception signal to the control section 136 .

The storage unit 133 is composed of a hard disk, a nonvolatile memory, or the like, and has a function of writing and storing various information and a function of reading various information. The storage unit 133 stores an analysis program for analyzing the grout filling state, various parameters input by the operator, and the like.

The operation unit 134 is composed of a keyboard or the like, and has a function of receiving an input operation by the operator.
The display unit 135 is configured by a liquid crystal display or the like, and has a function of displaying various information such as an input screen prompting input of various parameters and an analysis result screen showing analysis results.

The control unit 136 is composed of a CPU, a memory, etc., and has various processing functions related to the output of ultrasonic wave transmission signals to the surface transmission unit 11 and analysis of the grout filling state based on the reception signal from the surface reception unit 12. It has various processing functions and a function of controlling the operation of each unit connected via a predetermined bus.

Specifically, the control unit 136 has a processing function to control the operation of the surface transmission unit 11 and a surface reception unit 12 so as to continuously transmit 500 to 700 ultrasonic waves E every 3 to 5 mm seconds. and a processing function of creating an addition average wave based on the incident wave R continuously received by the receiver.

Furthermore, the control unit 136 has a processing function that enables the addition average wave to be displayed as a received wave, a processing function that stores the addition average wave in the storage unit 133, a processing function that determines the grout filling state, and the like. there is Note that these processing functions are realized by executing an analysis program.

When measuring sheath reflected P-waves, such a non-destructive inspection apparatus 10, as shown in FIG. They are arranged so that the distance a is any value from 110 mm to 200 mm.

According to the sheath reflected P wave measurement in FIG. 11, when the sheath cover thickness ds is shallow, the surface P ₁ wave, the surface S ₁ wave, and the direct wave (DI wave) mix on the sheath reflected P wave.

Furthermore, depending on the position of the concrete upper surface 4a, the intervals between the reinforcing bars arranged on the surface layer may become dense, and the reinforcing bar path wave and the reinforcing bar reflected wave are mixed directly on the sheath reflected P wave, and the sheath reflected P wave In the analysis of the grout filling state using waves, misanalysis of filling sheaths as empty sheaths frequently occurs. In order to deal with this problem, the sheath reflected S wave measurement of FIG. 12 is prepared.

FIG. 10 is a diagram that utilizes the phenomenon that the amplitude of the surface _P1 wave and the surface _S1 wave received by the surface receiving unit 12 is reduced by increasing the center-to-center distance a, and has information indicating the grout filling state of the sheath tube 2. FIG. 12(a), the direct wave (DI wave) in FIG. 12(b), and the mixed wave of the sheath self-oscillating wave in FIG. 12(c). , the reflected P-wave measurement or the reflected S-wave measurement is determined.

This determination is made by using the sheath cover thickness ds obtained by RC radar measurement or obtained by other means, and if the sheath cover thickness ds is 150 mm or more, the center distance a is any value from 110 mm to 200 mm. When the sheath cover thickness ds is shallower than 150 mm, the P-wave measurement is performed, and the reflected S-wave measurement is performed with the center-to-center distance of 375 mm or 500 mm.

On the other hand, the reflected P-wave measurement analysis is either single-point measurement using individual received waves shown in FIG. 11 or multi-point measurement (measurement points i=1 to nw) shown in FIG. 13(a). In the measurement analysis of FIG. 13(a), the received waves at the measuring points i = 1 to nw are added in order to eliminate the influence of unexpected interfering waves generated in the individual received waves at the measuring points i = 1 to nw. A method using mean waves in the analysis is also provided.

<Summary of sheath filling state threshold analysis>
Subsequently, the outline of the threshold analysis process will be explained using the reflected P-wave measurement analysis.
FIG. 14 is an explanatory diagram for explaining an outline of the threshold analysis processing of the grout filling state of the sheath tube 2 to be measured (hereinafter referred to as the sheath to be measured) performed by the control unit 136 of the nondestructive inspection apparatus 10. will be described with reference to FIG.

As the sheath to be measured used in this description, the sheath tube (sheath diameter φ _s 38, radar-measured cover thickness ds| _RC = 248 mm, second stage sheath cover thickness d _2s = 481 mm, plate thickness dw = 650 mm).

FIG. 14(a) shows the received wave spectrum F(f) | _i and the received wave G(t) _| showing. This is a case where a spectrum with large values occurs in the frequency _f1 band and the frequency _f2 band. Fig. 14(a) can be judged to have a spectral shape that is intermediate between Figs. 6(c) and 6(d).

The spectrum at the frequency _f2 of the sheath reflected wave in FIG. 2(b) is selected as the spectrum for analysis of the grout-filled state and will be described in detail.
The reason for excluding the spectrum at frequency f ₁ is that there is a risk that more of the spectrum of unanticipated probing jammers will be mixed into the lower frequency side.

In _the received _wave spectrum _F (f) _{| i=1 to 5} in FIG _. A spectrum obtained by extracting only the f ₀ and f ₂ spectra by multiplying the A _K (f) filter function (see FIG. 14(b)), which is one of the ranges, is the analysis spectrum FA(f)| _i=1 14(b) is obtained by setting GA(t)| _{i=1 to 5 as} the corresponding time series, and this is used as the spectrum and time series used in the analysis of the grout filling state.

Furthermore, in order to reduce the adverse effect on the analysis result of the waves generated in the front and rear of the sheath reflected P wave due to a reflection source other than the sheath to be measured, the cutout wave for analysis GB(t) _{| 5} (hereafter referred to as an analysis cutout wave) is obtained as shown in FIG. 15(a).

In this outline of threshold analysis, the time filter functions TGC1(t) and _TGC2 (t ₎ in FIG. are doing. The time filter function TGC1(t) is “0.0” at time t=0, a sine-shaped increasing function from time t=0 to _th , and “1.0” at time t= _th and above. .
On the other hand, the time filter function TGC2(t) has a sinusoidal shape that is “1.0” from time t=0 to _th , “1.0” at time t= _th , and “0” at time t=400 μs. Decreasing function.

シース反射Ｐ波起生時刻ｔ_ｐが既知の場合、対応するシースかぶり厚ｄｓは、式２で計算される。

If the sheath reflected P-wave occurrence time _tp is known, the corresponding sheath cover thickness ds is calculated by Eq.

ここで、０．５～０．７５の範囲でオペレータが設定する値を閾値α_σとし、以降の説明では閾値α_σ＝０．５として説明する。
図１５（ａ）の分析用切り出し波ＧＢ（ｔ）｜_{ｉ＝１～５}に対するスペクトル比較図は、図１５（ｂ）に示すスペクトルＦＢ（ｆ）｜_{ｉ＝１～５}のようになる。図１５（ｂ）を用いて、グラウト充填状態の分析用スペクトルを閾値α_σ＝０．５として、図１５（ｃ）のＦＣ（ｆ）｜_{ｉ＝１～５}を求めている。

Here, the value set by the operator in the range of 0.5 to 0.75 is set as the threshold α _σ , and the following description assumes that the threshold α _σ =0.5.
Spectrum FB(f)| _{i=1 to 5} shown in FIG. 15(b) are spectrum comparison diagrams for the analysis cutting wave GB(t)| _{i=1 to 5} in FIG. 15(a). Using FIG _. 15(b) _, FC(f)|

This processing sets a threshold value of α _σ in the spectrum of FIG. 6, and the frequency Spectrum shape conversion processing in which the maximum spectrum value on the lower frequency side than f _w is set to "1.0" and the maximum spectrum value on the higher frequency side than the frequency f _w is set to "threshold α _σ =0.5" is. In FIGS. 6(b) and 6(d), this process is shown in FIGS. 7(a) and 7(b) respectively.

In the time series of FIG. 16(a) corresponding to the spectrum subjected to spectral shape conversion with the threshold value α _σ =0.5 in _FIG . _The obtained _{sheath reflection P - wave} occurrence _time t _p is t _p | 16(b) is obtained by plotting the change in the maximum spectrum value SP _f2 of the frequency _f2 band obtained by multiplying the time series by the trapezoidal window function A each time, with time as the horizontal axis. Details will be described later in the fifth analysis process.

The maximum spectrum value SP _f2 to be displayed is based on the maximum spectrum value on the lower frequency side than the frequency _fw in the f ₀ and f ₂ spectra obtained for each movement of the trapezoidal window function A, which is set to “1.0”. It means the maximum spectral value on the higher frequency side than the frequency _fw . Henceforth, this analysis result SP _f2 (t) of FIG.16(b) is called "time sweep normalization spectral value SP _f2 ."
The sheath cover thickness ds=248 mm shown in FIGS. 16(a) and 16(b) is the cover thickness at the measuring point i=1 of the sheath to be measured separately measured by the RC radar.

In FIG. 16(b), at the time *=20 μsec later than the time t _p (=t _p | _RC ), the time sweep normalized spectrum value SP _f2 other than the i=4 wave is the threshold value α _σ =0.5 exceeds. Under this condition, the main measurement sheath (drilling empty) is determined to be "unfilled (empty)". In the spectrum of the extracted wave by the trapezoidal window function A at the time t _* = _tp +*= _tp | _{RC +} *, the maximum spectrum value on the lower frequency side than the frequency _fw and FIG. 17A shows SP _f2 (f, t _* ) obtained by comparing the maximum spectral value on the high frequency side and normalizing the larger spectral value to "1.0".

According to FIG. 17A, the spectrum values near the frequency f ₂ (=80 kHz) greatly exceed the threshold value α _σ =0.5 except for the measurement point i=4.
Furthermore, the occurrence state of the time sweep f ₀ and f ₂ spectrum of the average wave i=5 (No. 1 + No. 2 + No. 3 + No. 4, SP addition) is a diagram in which the horizontal axis is the frequency and the oblique axis is the time. 17(b).

FIG. 17(b) is a display for visually showing unfilled (empty), underfilled, and completely filled sheaths to be measured. In the spectrum obtained every time, the maximum spectrum value on the lower frequency side than the frequency _fw and the maximum spectrum value on the higher frequency side are compared, and the larger spectrum value is normalized to "1.0". The resulting SP _f2 (f,t) ^nc | _i=5 (hereinafter referred to as the time-swept f ₀ , f ₂ spectrum) is denoted as nc=2.

Hereinafter, the time sweep f ₀ , f ₂ spectrum SP _f2 (f, t) is an FFT spectrum in order to more clearly show the state of unfilled (empty), underfilled, and completely filled by visual analysis results. MEM (maximum entropy method) spectrum is replaced and displayed.

It should be noted that MEM spectra, while recognized in mathematics, have not been used as a common method in engineering and mechanics. However, in a spectrum corresponding to an extremely short time series cut out by the trapezoidal window function A, the precision is extremely high compared to the FFT spectrum.

By the way, in an existing PC bridge, the difference between the cover thickness of the second stage sheath and the sheath to be measured may be around 100 mm, and the difference from the plate thickness of the sheath to be measured may be about 100 mm.
In addition, when the grout filling state is investigated under the condition that these relationships are not grasped, erroneous determination of the grout filling state frequently occurs.

For example, if reflected P waves of the second stage sheath and plate thickness with large amplitudes are mixed in the cutout wave for analysis, the frequency of these reflected waves will appear in the thresholded spectrum of FIG. The presence of a large amount of spectrum at _f2 results in misjudgment of the grout filling state.

One way to deal with this problem is to narrow the time band of the analysis clipping wave shown in FIG. 15(a) as much as possible. FIG. 18(a) is an example of the cutout wave for analysis that has achieved this countermeasure. In FIG. 18(a), vertical cursors indicate the occurrence times of the reflected P waves of the second-stage sheath or stencil thickness, which are assumed to exist 100 mm and 150 mm behind the cover thickness of the sheath to be measured.

No. 1 corresponding to the cutout wave for analysis in FIG. 18(a). 1 to No. 4 received wave, No. 5 is shape-transformed using the threshold value α _σ =0.5, a spectrum comparison diagram of FIG. 18(b) is obtained instead of FIG. 15(c).

19(a) is obtained by obtaining the time-swept standardized spectrum value SP _f2 corresponding to FIG. 16(b) from the threshold-processed spectrum of FIG. 18(b). Comparing FIG. 16(b) and FIG. 19(a), there is a difference in spectral value, but the shapes are substantially the same.

As a result, in the analysis of the grout filling state by reflection P wave measurement, if it is essential to use the cutting wave for analysis as a cutting wave in a narrow time band as shown in _FIG . It is possible to automatically eliminate erroneous determination of the grout filling state due to the presence of direct waves (DI waves) transmitted through shallow dives, second-stage sheaths, or slab thickness reflected waves. For this reason, in the analysis example used in the following description, the time series used for the analysis is the clipping wave of the narrow time band shown in FIG. 18(a).

Next, the "method for confirming the state of grout filling" using the time-swept standardized spectrum value SP _f2 will be described.
In FIG. 19(a), the sheath cover thickness ds to be measured in Equation 1 is replaced with the radar-measured cover thickness ds| _RC by RC radar measurement, and the sheath reflection P wave occurrence time _tp is replaced with _tp | _RC . The sheath reflection P-wave occurrence time _tp | _RC is indicated by a vertical cursor as in FIG. 16(b). However, in addition to _the vertical cursors indicating the radar-measured fog _{thickness ds} | _RC ^and the sheath reflection P-wave occurrence time _{t h =} t _{p |} (Note that ds ^~ represents a symbol with “~” above ds in formulas and drawings. The same applies hereinafter).

According to FIG. 19(a), it can be determined that the time indicated by the circle is near the time when the sheath reflected P-wave occurs from the history of the temporal change of the time-swept normalized spectrum value SP _f2 . The sheath covering thickness varies between measurement points i = 1 and 2 (No. 1 and No. 2 in the figure) and measurement points i = 3 and 4 (No. 3 and No. 4 in the figure). . Although it is an approximate value, the time of occurrence at measuring points i = 1 and 2 is Δt _v1 (= 6 μs) behind the time of occurrence of the radar-measured cover thickness ds| _RC , and at measuring points i = 3 and 4 is later than Δt _v2 (=17 μsec).

In this example, Δt _p is the average value of Δt _v1 and Δt _v2 , and the sheath reflection P-wave occurrence time t _h obtained by Equation 1 is changed using Equation 3 below.

式２でシース反射Ｐ波起生時刻ｔ_ｐをｔ_ｐ｜_ＲＣ＋Δｔ_ｐに置き換えて得た計測対象シースかぶり厚ｄｓを、分析用かぶり厚ｄｓ^～＝２７１ｍｍとして、その位置を縦カーソルで追加表示している。
さらに、図１９（ａ）では、シース反射Ｍ_１波の起生時刻ｔ_Ｍ１に関する時刻ｔ_Ｍ１｜_ＲＣ、及び時刻ｔ_Ｍ１｜_ｄｓ ^～を縦カーソルで示している。

The sheath cover thickness _{ds to} be measured obtained by ^replacing the sheath reflection P-wave occurrence time _tp with _tp | are doing.
Furthermore, in FIG. 19(a), _the time _{t M1 | RC} ^and the time t _{M1 |}

The time t _M1 | _RC is the time at which the sheath reflection _M1 wave occurs when the sheath cover thickness _is defined as the radar-measured cover thickness ds| _RC . Equations 5 and 6 are applied to the occurrence time _tp of the sheath reflection P wave to be obtained by replacement to obtain the occurrence time _tM1 of the sheath reflection _M1 wave, which is defined as time _tM1 | _RC . The occurrence time of the sheath reflection _M2 wave is shown in Equation 6.

時刻ｔ_Ｍ１｜_ｄｓ ^～はシースかぶり厚を分析用かぶり厚ｄｓ^～としたときのシース反射Ｍ_１波の起生時刻であり、式４のシースかぶり厚ｄｓを分析用かぶり厚ｄｓ^～に置き換えて求めるシース反射Ｐ波起生時刻ｔ_ｐを式５、及び式６に適用してシース反射Ｍ_１波の起生時刻ｔ_Ｍ１を求め、これを時刻ｔ_Ｍ１｜_ｄｓ ^～としている。

The time t _M1 | _ds ^~ is the time when the sheath reflection M ₁ ^wave occurs when the sheath cover thickness is set to the analytical cover thickness ds ^{~ .} The sheath reflection P wave occurrence time t _p to be obtained is applied to Equations 5 and 6 to obtain the occurrence time t _M1 of the sheath reflection M ₁ wave, which is _defined ^as time t _M1 |

In the acquisition of the cutout wave for analysis in FIG. 18(a), the sheath reflection P wave occurrence time t _h = t _p is changed to the sheath reflection P wave occurrence time t _h = t _p + Δt _p = 119.6 + 11 = 130.6 μsec. (ds ^∼ =271 mm) and reanalyzed, we obtain the time-swept normalized spectral value SP _f2 in FIG. 19(b) instead of FIG. 19(a).
In addition, in FIG.19(b), No. Two kinds of five-addition average waves are displayed.

In FIG. 19(b), No. indicated by a solid line. 5SP addition is spectral addition of measuring points i=1 to 4 (hereinafter referred to as SP addition), and the corresponding time-series phase information adopts that of WAVE addition. On the other hand, in FIG. 19(b), No. indicated by a dotted line. 5 is WAVE addition.
By the way, an empty-fill determination cursor is defined, and the time is obtained by the following equation (7).

なお、時刻＊値は、分析用シースかぶり厚をレーダ計測かぶり厚ｄｓ｜_ＲＣとする図１９（ａ）では時刻＊＝２０μ秒としたが、分析用かぶり厚ｄｓ^～とする図１９（ｂ）では、時刻＊＝１６μ秒としている。この値の適正なる設定値は、後述する「閾値を用いた反射Ｐ波自動化分析」で示す表２に分析用１次かぶり厚ｄｓ_（１）ごとに整理している。

Note that the time ^* value is set to time * = 20 μsec in _FIG . Then, time *=16 μs. Appropriate set values for this value are arranged for each primary cover thickness ds ₍₁₎ for analysis in Table 2 shown in "Automated Reflected P-wave Analysis Using Threshold" to be described later.

Furthermore, measurement data (sheath diameter φ _s 38, drilling cover thickness ds | _drilling = 165 mm, 2nd stage Sheath cover thickness d _2s =400 mm, plate thickness d _w =550 mm, concrete longitudinal wave speed V _p =4261 m/sec).

In this analysis example, since the radar-measured cover thickness ds| _RC by RC radar measurement is unknown, the radar-measured cover thickness ds| _RC is adopted as the same value as _{the drilling} cover thickness ds| And it is confirmed that the grout filling state is completely filled by drilling. In this case, instead of FIG. 19(a), the time-swept standardized spectrum value SP _f2 can be obtained as shown in FIG. 20(a).

There are three types of sheath reflected waves: sheath reflected P wave, sheath reflected _M1 wave, and sheath reflected _M2 wave. , sheath reflection P wave occurrence time t _p , sheath reflection M ₁ wave occurrence time t _M1 , and sheath reflection M ₂ wave occurrence time t _M2 are respectively _{reduced to} occurrence time t _p | and occurrence time t _M1 | The vertical cursor indicates the occurrence time _{t M2} | _shaving .

Furthermore, from Equations 5 and 6, the relationship between the sheath reflection P-wave occurrence time t _p and the sheath reflection _M1 wave occurrence time t _M1 is: concrete transverse wave speed V _s /concrete longitudinal wave speed V _p =0. 62 is defined in Equation 8 below.

これら振動数ｆ_２＝８０ｋＨｚ成分のシース反射Ｍ_１波、及びシース反射Ｍ_２波の振幅は、中心間距離ａの狭い反射波計測の場合、絶対量として小さい値である。加えて、図１８（ａ）のＴＧＣ２（ｔ）処理で、さらにその振幅が縮小されるため、極々小さい値となっている。

The amplitudes of the sheath reflected _M1 wave and the sheath reflected _M2 wave of the frequency f ₂ =80 kHz component are small absolute values in the case of reflected wave measurement with a narrow center-to-center distance a. In addition, the TGC2(t) processing in FIG. 18(a) further reduces the amplitude, resulting in an extremely small value.

However, in FIG. 20(a) showing changes in _the time-swept normalized spectral value SP _f2 obtained for each movement of the trapezoidal window function A shown in FIG. Since the spectrum values are normalized to "1.0", the spectrum values of the sheath reflection _M1 wave and the sheath reflection _M2 wave are displayed as large values.

This numerical analysis phenomenon is used to correct the sheath reflection P-wave occurrence time _tp caused by erroneous measurement of radar measurement cover thickness _ds | be able to. Judging that the correct sheath reflection _M1 wave occurrence time t _M1 in _FIG . , from Equation 8 obtained from Equation 6, if the sheath reflection P-wave occurrence time t _p is changed to 0.76t _M1 , the corresponding sheath cover thickness ^ds is calculated by Equation 9 obtained by rewriting Equation 4. can.

なお、図２０（ａ）に記載されているΔｔ_ｐは、式１０で計算されている。

Δt _p shown in FIG. 20( a ) is calculated by Equation 10.

これにより、分析で用いるシースかぶり厚をレーダ計測かぶり厚ｄｓ｜_ＲＣ（＝削孔かぶり厚ｄｓ｜_削）からｄｓ^～に変更して再分析すれば、図２０（ｂ）の分析結果を得る。
時刻ｔ_＊で測点ｉ＝１～４、加算平均波ｉ＝５の全ての時刻掃引基準化スペクトル値ＳＰ_ｆ２が閾値α_σ＝０．５を下回る状況を確認できる。このような時刻掃引基準化スペクトル値ＳＰ_ｆ２が得られた場合、「完全充填」と判断する。空充填判定カーソル時刻ｔ_＊は、ｔ_ｐ＝ｔ_ｐ｜_ＲＣ（本分析例では、ｔ_ｐ｜_削とする）として、式１１で計算される。

Accordingly, if the sheath cover thickness used in the analysis is changed ^from the _radar - _measured cover thickness ds|
It can be confirmed that all the time-swept normalized spectrum values SP _f2 of the measurement points i=1 to 4 and the addition average wave i=5 are below the threshold value α _σ =0.5 at the time t _* . When such a time-swept normalized spectrum value SP _f2 is obtained, it is determined as "complete filling". The empty-fill determination cursor time t _* is calculated by Equation 11 as _tp = _tp | _RC (in this analysis example, _tp | _removal ).

なお、本分析例では、時刻＊を後述する表２を用いて、時刻＊＝１４μ秒としている。
さらに、図２０（ｂ）の時刻ｔ_＊＝ｔ_ｐ｜_削＋Δｔ_ｐ＋＊での時刻掃引ｆ_０，ｆ_２スペクトルＳＰ（ｆ，ｔ_＊）を図２１（ａ）に示す。

In this analysis example, time* is set to time*=14 μs using Table 2 to be described later.
Furthermore, the time sweep f ₀ , f ₂ spectrum SP(f, t _* ) at the time t _* =t _p | _cut +Δt _p +* in FIG. 20(b) is shown in FIG. 21(a).

It can be confirmed that the time sweep f ₀ , f ₂ spectrum SP(f, t _* ) is below the threshold value α _σ =0.5 for all the received waves at the measurement points i=1 to 4. Time sweep f ₀ , f ₂ spectrum SP _{f 2 (2)} (f, t) ^nc _| b). When such a spectral shape is visually recognized, the sheath to be measured is judged to be "completely filled".

<Reflected P-wave automated analysis using threshold>
In the analysis shown in the above-mentioned "Overview of Sheath Filling State Threshold Analysis", the ultra-narrow band time series shown in _FIG . It eliminates erroneous determination of the grout filling state due to the presence of direct waves (DI waves) that propagate shallowly and reflected waves from the second sheath or plate thickness.

However, such countermeasures alone cannot completely eliminate erroneous determinations.
Problems that cause erroneous determination in the reflected P-wave automated analysis and countermeasures are listed below, and the analysis flow for dealing with these problems is shown in FIGS. 22 to 24. FIG.

First, the first problem (hereinafter referred to as problem (1)) is an erroneous determination of the grout filling state due to erroneous settings of the radar-measured cover thickness ds| _RC and the concrete longitudinal wave sound velocity _Vp . be. The sheath reflection P-wave occurrence time t _p value used in the analysis narrowband time series acquisition of FIGS _. It is calculated by replacing ds with the radar-measured cover thickness ds| _RC . The radar-measured cover thickness ds| _RC is often different from the actual value due to an erroneous setting of the concrete dielectric constant or the like.

Furthermore, the concrete longitudinal wave speed V _p used in Equation 1 must be measured at a location different from the location where the received wave directly above the sheath to be measured shown in FIG. do not get Due to the difference in concrete casting date and time between these two locations, it cannot _be denied that there is a difference in casting conditions such as the water-cement ratio. .

For this reason _, using the _sheath reflection P wave occurrence time t _{p | RC} obtained by applying the radar measured cover thickness _{ds |} | _RC ) as a reference value, the cutout wave of FIG. 15A or FIG.

According to numerous analytical cases, the incidence of misjudgment of measured grout filling status due to this problem can be 50% or more. This problem needs to be addressed.

The second problem (hereafter referred to as problem (2)) is that when the sheath cover thickness to be measured becomes shallow, the concrete surface _S1 wave with a large amplitude precedes the occurrence time of the sheath reflected P wave. And a direct wave (DI wave) is generated, and a reflected wave with a large amplitude is generated from the second stage sheath, the plate thickness, and the bottom corner of the plate thickness after the sheath reflection P wave occurrence time, and the grout filling It may adversely affect the analysis of the state and exhibit false positives. In order to avoid this problem, in the analysis, it is essential to use the ultra-narrow band time series shown in FIG. 18(a) as the cutout wave for analysis.

The third problem (hereinafter referred to as problem (3)) is that in the first analysis process (step S104 in FIG. 22), i=nA to nB (FIG. 27 , see Table 1), any of the measurement points between them may happen to be the boundary area between the gap and the filled portion. An analytical method that addresses this problem needs to be prepared to automatically determine boundary stations i=n1.

In a sixth analysis process (step S112 in FIG. 23), which will be described later, it is specified whether the spectral shape of the time-swept normalized spectral value SP _f2(1) (t)| _i has the characteristic TA or the characteristic TB. , in the case of characteristic TA, the grout filling state is determined in a seventh analysis process (steps S114 to S116 in FIG. 24), which will be described later.

In the case of multi-point measurement with nw>1, the judgment result is "unfilled (empty)" or "insufficient filling" at all measuring points i = nA to nB, or "unfilled" at measuring points i = nA to n1. "filled (empty)" or "underfilled", and "fully filled" at stations i=n1+1 to nB. In the case of a single point measurement with nw=1, there will be only i=1 station and it will be "unfilled" or "underfilled".

In the case of characteristic TB, the grout filling state is determined in the eighth analysis process (steps S117 to S119 in FIG. 24), which will be described later. In the case of multi-point measurement with nw>1, the judgment result is "complete filling" at all measuring points i = nA to nB, or "complete filling" at measuring points i = nA to n1, and At the measurement point i=n1+1 to nB (where n1<nB), it becomes "unfilled (empty)" or "insufficiently filled". For a single point measurement with nw=1, there will be only i=1 stations and a "full fill".
Specific analysis examples of the above-described processing are performed using analysis examples 1 and 2 shown in Table 3 in the "threshold reflection P-wave automated analysis example" described later.

The fourth problem (hereinafter referred to as problem (4)) is that the sheath cover thickness to be measured may vary greatly in its longitudinal direction. If the measurement analysis considering this change is not performed, the grout filling state is erroneously determined.

To deal with this problem, we are preparing two processes. The first process is the first analysis process (step S104) in FIG. 22 in the flow of automated analysis to be described later. Cover thickness ds ( _{1 )} , or ds ₍₁₎ | _large and ds ₍₁₎ | Primary cover thickness ds ₍₁₎ in (1) represents a letter enclosing a number in parenthesis with a circle, and is indicated by the enclosing letter in the drawings to be described later (the same shall apply hereinafter).

In the second process, under the condition of problem (4), the phase information of the wave received at each station changes. As a result, even if all of the measuring points i = 1 to nw (nw = 4) are "unfilled (empty)", the average wave (WAVE summation) by time series is the sheath reflection of each measuring point i P-waves are often out of phase and exhibit a "fully filled" or "underfilled" appearance. Therefore, it is necessary to prepare an analysis function to deal with this problem by using the average wave (SP summation) of the spectra of the measurement points i=1 to nw. A specific example of analysis is shown in FIG. 39(a) using analysis example 4 shown in Table 3 in the "threshold reflection P-wave automated analysis case" described later. In addition, No. in FIG.39(a). The solid line of No. 5 is SP addition. The dashed line at 5 is the WAVE addition.

22, 23, and 24 (input receiving process, first recording process, second recording process, and second 1 to 8) will be described with reference to FIGS. 22 to 27. FIG.

First, when the analysis program is executed by the operator's operation, the control unit 136 of the analysis device 13 starts input acceptance processing as shown in FIG. 22 (step S101). At this time, the control unit 136 receives the operator's input operation, acquires the concrete longitudinal wave speed V _p , the cover thickness d2s of the second stage sheath, the plate thickness dw, and the path length dwc of the bottom corner of the plate thickness, Move to the first recording process. If the covering thickness d2s of the second stage sheath, the plate thickness dw, and the path length dwc of the bottom corner of the plate thickness are unknown, the input reception processing is skipped by the operator's input operation, and the process proceeds to the first recording processing. do.

Here, the concrete longitudinal wave velocity _Vp is obtained by ultrasonic measurement at a site where the concrete thickness can be confirmed on a scale, such as the girder beam of the PC bridge to be measured or the partition wall of the internal space.
Also, the cover thickness d2s of the second stage sheath, the plate thickness dw, and the path length dwc of the bottom corner of the plate thickness are the values at the measurement position of the sheath to be measured obtained from the structural drawing.

Next, the first recording process (step S102 in FIG. 22) will be described. In RC radar measurement, at the time of multi-point measurement, the sheath cover thickness ds at measurement point 1 and measurement point nw are measured as ds| _{RC left} and ds| _{RC right,} respectively, and radar measurement cover thickness ds| _RC = ( Calculate ds| _{RC left} + ds| _{RC right} )/2.

Furthermore, using the concrete longitudinal wave speed _{V p} acquired in step S101, the occurrence time t _p | _RC of the reflected wave is changed _to t _p | The fogging thickness ds is replaced with the radar-measured fogging thickness ds| _RC . When a single-point measurement is assumed, the radar-measured cover thickness ds| _RC at the measurement point i=1 is recorded, and the occurrence time _tp | _RC is obtained in the same manner as in the case of multi-point measurement.

Next, the second recording process (step S103 in FIG. 22) will be described. On the concrete upper surface 4a (see FIG. 8) directly above the sheath to be measured, the center-to-center distance a between the transmitting probe 11a and the receiving probe 12a is set to 110 mm to 200 mm, and the number of multipoint measurement points is nw = 4. Wave group G(t)| _{i = 1 to nw} is measured at measurement points i (No. .3, No. 4). Note that nw=1 for single-point measurement.

As for the received waves, ultrasonic waves are continuously transmitted 500 times every 5 mm seconds into the concrete interior toward the sheath to be measured. Calculated by averaging.

Next, the first analysis process (step S104 in FIG. 22) will be described. As described above, due to the problem (1), the radar-measured cover thickness ds| _RC may differ from the actual value, making it difficult to determine the grout filling state. Therefore, it is necessary to establish a method for accurately obtaining the reflected P-wave occurrence time of the sheath to be measured.

The primary occurrence time of the sheath-reflected P-wave is tp ₍₁₎ , which is obtained by the first analysis process. Note that ( _{1) in tp(} 1) represents a character enclosing a number in parentheses with a circle, and is illustrated by the enclosing character in the drawings to be described later.

FIG. 26A shows an example of the spectrum and time series of received ultrasonic waves measured with the center-to-center distance a of 200 mm at one measuring point of the sheath to be measured. For the received wave in the right diagram of FIG. 26(a), using the radar-measured cover _{thickness ds} | Occurrence time tp|RC = 125.5 µs obtained by replacing the sheath cover thickness ds in Equation 1 with the radar-measured _cover thickness ds| _RC and the sheath reflected P-wave occurrence time _tp with the occurrence time _tp | _RC = 125.5 µs _. is indicated by a vertical cursor.

In addition, the F3(f) filter function for spectrum extraction is indicated by a dotted line in the left diagram of FIG. 26(a).
Note that the F3(f) filter function is "0.0" between the frequency 0.0 and (f _s -Δf _s ), and "0.0" between the frequency (f _s -Δf _s ) and f _s . 0 to 1.0" sin-shaped decreasing function between frequency f _s and (f _s +Δf _s ) is between "1.0 and 0.0", frequency (f _s +Δf _s ) is a function that becomes “0.0” above, and its initial shape is set to center frequency f _s =80 kHz and Δf _s =40 kHz.

The control unit 136 expands the spectrum shown in FIG. 26(a) from i=3 to i=1 to nw to find the received wave spectrum F(f)| _{i=1 to nw} , and obtains the F3(f) filter function After multiplication, the time-series wave obtained by the inverse FFT transform is multiplied by the time filter function TGC4(t) having the center time at the sheath reflection P-wave occurrence time t _p =t _p | _RC to obtain the spectrum shown in FIG. , and the corresponding time-series waves G(t)| i _{= 1 to nw} are obtained.

Furthermore, the control unit 136 receives an operator's operation via the operation unit 134 to gradually shift the center frequency _fs of the F3(f) filter function to the low frequency side or the high frequency side.
At this time, every time the central frequency _fs of the F3(f) filter function is moved to the low frequency side or the high frequency side, the control unit 136 changes the F3(f) filter function to the received wave spectrum F(f)| After multiplying by _i , time-series wave _G (t ₎ | Each time the time-series wave G(t) _| there is

In this way, the control unit 136 converts the central time of the time filter function TGC4(t) to the sheath reflected P wave at any measuring point _i of the time-series wave G(t) | By moving to the occurrence time, the occurrence time of the time-series wave generated in the vicinity of _the sheath reflection P wave occurrence time t _p | It is defined as time t _p(1) | _i .
Furthermore, the _control unit 136 defines the corresponding primary cover thickness for analysis as ds _{(1) |} At time _tp(1) | _i , the sheath cover thickness ds is replaced with the primary cover thickness ds ₍₁₎ | _i for analysis, and the primary cover thickness ds ₍₁₎ | _i for analysis is obtained for each measurement point i. there is

Note that the time filter function TGC4(t) is such that the time t = 0.0 to (t _p | _RC - Δt _{k )} is " 0.0” at _time t=(t _p | _RC −Δt _{k )} , a sinusoidal increasing function that becomes “0.0” at time t=( _{t p} | A sine-shaped decreasing function that becomes “1.0” and becomes “0.0” at time t = (t _p | _RC + Δt _k ), and becomes “0.0” after time t = (t _p | _RC + Δt _k ) is a function of shape.

The right figure of FIG. 26(b) obtained by applying the F3(f) filter function and the time filter function TGC4(t) to the received wave of FIG _{. (1)} is clearly shown. In the right diagram of FIG. 26(b), the center time of the above time filter function TGC4(t) is changed from _tp | _RC to _tp(1) .

In this example, the sheath cover thickness ds ₍₁₎ is as deep as 225 mm. As a result, the phenomenon that the surface _S1 wave of the concrete surface and the backward residual wave of the direct wave (DI wave) are mixed on the sheath reflected P wave of the above-mentioned problem (2) is eliminated, and the reflected P wave is Although it is clearly shown, due to unexpected mixing of exploration interference waves due to reinforcing bars densely arranged in the surface layer, fine cracks that cannot be seen on the surface layer, etc., the primary reflected P wave for analysis occurs at the time t _{p (1)} can be difficult to identify.

In _this case, as described above, the time filter function TGC4 By moving the center time of (t) to the starting point of the generated wave, the analysis primary reflected P-wave generation time _tp(1) can be accurately specified. FIG. 28(b) with the frequency _fs of analysis example 1 of the "threshold reflection P wave automated analysis example" described later as 82 kHz, FIG. 32(a) with the frequency _fs of analysis example 2 as 100 kHz, analysis example 35(a) where the frequency f _s of Example 3 is 96 kHz, and FIG. 38(a) where the frequency f _s of Analysis Example 4 is 96 kHz.

According to FIG. 26(b), the analysis primary reflected P-wave occurrence time _tp(1) becomes 109.6 μs near the occurrence time _tp | _RC =125.5 μs, and the occurrence time t A difference of 16 μs can be confirmed between _p | _RC and the primary reflected P-wave occurrence time _tp(1) for analysis. The sheath cover thickness ds obtained by replacing the occurrence time t _p in Equation 2 with the analysis primary reflected P-wave occurrence time t _{p (1)} becomes the analysis primary cover thickness ds ₍₁₎ (=225 mm), There is a difference of 35 mm from the radar-measured fog thickness ds| _RC (=260 mm).

If the concrete longitudinal wave speed V _p differs from the actual value, the analytical primary cover thickness ds ₍₁₎ value also differs from the actual value. By using _p(1) , misidentification of the primary cover thickness ds ₍₁₎ for analysis does not cause misjudgment of the grout filling state.
The spectrum of the time series (thick line) obtained by multiplication of this time filter function TGC4(t) is shown in the left diagram of FIG. 26(b).

In this analysis example, the analysis primary reflected P-wave occurrence time _tp(1) is specified very clearly, but there are many measurement examples in which this specification is difficult. In this case, while the center frequency f _s =80 kHz is gradually moved toward higher or lower frequencies, the time filter function TGC4(t) is moved around the time axis. The P-wave occurrence time _tp(1) can be accurately specified.

Furthermore, due to the problem (4) described above, the primary cover thickness for analysis ds ₍₁₎ (the primary reflected P-wave occurrence time for analysis t _p(1) ) at each measurement point i (=1 to 4) is There are many examples of varying measurements. In order to deal with this problem, the analysis primary reflection P-wave occurrence time _tp(1) is obtained for each measurement point in the above analysis, and as shown in FIG. The changes in the cover thickness ds ₍₁₎ are patterned and designated as "pattern (0),""patterns (1) to (4)," and "patterns (1') to (4'). The primary cover thickness is classified into three types, ds ₍₁₎ , ds ₍₁₎ | _large , and ds ₍₁₎ | _small , and the grout filling state is analyzed at each measurement point of this cover thickness.

For example, if "pattern (0)" in FIG. 27, No. From 1 measuring point No. At all four measurement points, the primary cover thickness for analysis is ds ₍₁₎ .
If "Pattern (1)" in FIG. 27, No. The primary cover thickness ds ₍₁₎ | ₁ for analysis at one measuring point _becomes ds ₍₁₎ | 2 stations, No. 3 stations, and No. The average value of the primary cover thicknesses ds ₍₁₎ | ₂ , ds ₍₁₎ | ₃ , and ds ₍₁₎ | ₄ for analysis at the four measurement points is _smaller than ds ₍₁₎ |.

No. after this. In the analysis of the grout filling state at one measuring point, _{the large} ds ₍₁₎ | 2 stations, No. 3 stations, and No. In the analysis of the grout filling state at four measurement points, ds ₍₁₎ | _small is taken as the primary cover thickness for analysis.

If "pattern (2')" in FIG. 27, No. The primary cover _thickness for analysis at one measuring point ds ₍₁₎ | The _average value of the primary cover thickness ds _{( 1 )} | Analytical primary cover thickness ds ( _{1 )} | The average value of the primary cover thickness ds ₍₁₎ | ₄ for analysis at the four measurement points becomes ds ₍₁₎ | _large .

No. after this. 1 station, and No. In the analysis of the _grout filling state at two measurement points, ds ₍₁₎ | 3 stations, and No. In the analysis of the filling state at four measuring points, _{the large} ds ₍₁₎ | is taken as the primary cover thickness for analysis.

In addition, even in "patterns (2), (3), (4)" and "patterns (1'), (3'), (4')" in FIG. 27, "patterns (1), (2' )”, ds ₍₁₎ | _large or ds ₍₁₎ | _small is used as the primary cover thickness for analysis, and the combination of measurement points i for analyzing the grout filling state is specified.

Arranging the above, for each pattern primary cover thickness ds ₍₁₎ or ds ₍₁₎ | _large or ds ( _{1 )} | , and the number of multipoint measurement points nw=4.

なお、表１において、単一点計測の場合、「パターン（０）」、かつ開始測点ｎＡ＝１、終了測点ｎＢ＝１とする。
また、表１において、ｎｗ値が「４」を超える場合、ｎｗ値に応じてパターン数が増加する。
表１を用いて、分析用１次かぶり厚ｄｓ_（１）、またはｄｓ_（１）｜_大、あるいはｄｓ_（１）｜_小ごとに対応する測点ｉのグラウト充填状態を以降の分析で判定する。

In Table 1, in the case of single-point measurement, "pattern (0)", starting point nA=1, and ending point nB=1.
Also, in Table 1, when the nw value exceeds "4", the number of patterns increases according to the nw value.
Using Table 1, the grouting state of the measuring point i corresponding to each primary cover thickness ds ₍₁₎ for analysis, or ds ₍₁₎ | _large , or ds _{(1) |} .

Next, the second analysis processing (step S105 in FIG. 22) will be described. In the second analysis process, the received wave spectrum F( _f )| _{i = 1 to nw+1} are multiplied by the A _K (f) filter function to obtain the analysis spectrum FA(f)| _{i=1 to nw+1} shown in FIG. 14(b), and the corresponding analysis time series GA(t)| _{i =1 to nw+1} are obtained by inverse FFT.

The A _K (f) filter function is a sinusoidal increasing function from frequency f = -10 kHz to f ₀ from 0.0 to 1.0, and from frequency f = f ₀ to f _w from 1.0 to 0.0", a sin-shaped increasing function from frequency f= _fw to _f2 from "0.0 to 1.0", from frequency f= _f2 to ( _f2 +30kHz) It is a sine-shaped decreasing function that is "1.0 to 0.0" and a function that is "0.0" above the frequency f=(f ₂ +30 kHz). Note that the center frequency f ₀ is (f _w −10 kHz) / 2 ≈ 20 kHz, and the frequency f _w is set by the operator in the range of 50 kHz - Δf _w < f _w < 50 kHz + Δf _w (where Δf _w = 5 kHz) and the frequency _f2 is 80 kHz.

After the second analysis process, the analysis of the grout filling state for each sheath cover thickness pattern in Table 1 created in the above-described first analysis process is transferred to the first process through step S106 in FIG. 22, or This is done in the second processing and the third processing.

More specifically, when the pattern created in the first analysis process described above is "pattern (0)" (step S106: No), the first process is shifted to "pattern (1) to (4)". , and “patterns (1′) to (4′)” (step S106: Yes), the process proceeds to the second process, and then to the third process.

The first process (step S107 in FIG. 22) analyzes and determines the grout filling state of the primary covering thickness ds ₍₁₎ for analysis of "Pattern (0)" in Table 1, which does not have the above problem (4). do. Using the start measurement point nA and the end measurement point nB of "Pattern (0)" in Table 1, the measurement target sheath where the grout filling state is the same at measurement points i = nA to nB, or problem (3) The analysis determination is terminated by dealing with the sheath to be measured that has a boundary between the void and the filled portion. It should be noted that the first process also deals with the analysis decision of a single point measurement (measurement point i=1).

The second process (step S108 in FIG. 22) is for "patterns (1) to (4)" and "patterns (1') to (4')" in Table 1 having problem (4) described above. _Primary cover thickness for analysis ds ₍₁₎ | Using the start measurement point nA and the end measurement point nB for each pattern in Table 1, the measurement target sheath where the grout filling state is the same at the measurement point i = nA to nB, or the problem at the measurement point i = nA to nB After dealing with the sheath to be measured that has a boundary between the gap and the filling portion in (3), the third process is performed. Note that the second process does not address the analytical determination of single point measurements.

The third process (step S109 in FIG. 22) is for "patterns (1) to (4)" and "patterns (1') to (4')" in Table 1 having problem (4) described above. _Primary cover thickness for analysis ds ₍₁₎ | Using the start measurement point nA and the end measurement point nB for each pattern in Table 1, the measurement target sheath where the grout filling state is the same at the measurement point i = nA to nB, or the problem at the measurement point i = nA to nB (3) The analysis determination is completed by dealing with the sheath to be measured that has a boundary between the gap and the filling portion. Note that the third process does not address analytical determination of single point measurements.

FIG. 22 shows the flow of sheath reflection P-wave threshold analysis, of which the first process (step S107 in FIG. 22) is shown in FIGS. 23 and 24. FIG.
The second process (step S108 in FIG. 22) is the same as the first process. However, the primary reflected P-wave occurrence time for analysis _tp(1) and the secondary reflected P-wave occurrence time for analysis _tp(2) described later are set to tp ₍₁₎ | _large and _{tp( 2)} │ is replaced with _large .

The contents of the third process (step S109 in FIG. 22) are the same as those of the first process. However, the analysis primary reflected P-wave occurrence time _tp(1) and the analysis secondary reflection P-wave occurrence time _tp(2) , which will be described later, are set to _tp(1) | _small and _{tp( 2)} The processing is performed by replacing | _small .

Here, the first processing will be described in detail. As shown in step S111 of FIG. 23, the first process is the continuous third analysis process, fourth analysis process, and fifth analysis process, which are performed to analyze the "pattern (0)" of the sheath cover thickness. We start with the primary fog thickness ds ₍₁₎ for analysis (the primary reflected P-wave occurrence time t _p(1) for analysis).

First, the third analysis process multiplies the time _{series for} analysis GA(t) | The cutout wave for analysis GB ₍₁₎ (t)| _{i=1 to nw+1 shown} in FIG. 15(a) is obtained, and the corresponding spectrum FB ₍₁₎ (f)| b) as shown.

Note that the analysis cutting wave GB ₍₁₎ (t)| _i and the spectrum FB ₍₁₎ (f)| _i used in the subsequent analysis are the poles of FIG. A narrow time band clipping wave is used. This is to address problem (2) above, by combining the concrete surface _S1 wave, the direct wave (DI wave), and the large amplitude reflections from the second sheath, the slab, and the bottom corners of the slab. This is a countermeasure for removing or reducing the adverse effects of waves and the like on the determination result of the grout filling state. Furthermore, for similar measures, the settings of the time filter function TGC1(t) and the time filter function TGC2(t) are changed.

The time filter function TGC1(t) assumes that the reference time is t _h = t _{p (1)} + Δt _h1 (Δt _h1 = 6 μs), becomes “0.0” at time t = 0.0, and becomes “0.0” at the reference time _t TGC1(t)=(TGCA( ^t ))ne using a sine-shaped increasing line segment that is "1.0" and a TGCA(t) function that is "1.0" after time t= _th (However, ne=50).

In addition, the time filter function TGC2(t) assumes that the reference time is t _h =t _p(1) , the time t = 0.0 to t _h is "1.0", and the time t = t _h is "1.0 ”, TGC2 (t) = ( TGCB(t)) ^nf (however, nf=150).

Note that Δt _h1 , ne, and nf will be the time-swept standardized spectrum values SP _f2(2) (t)| _{i=1 to nw+1} and the time-sweep f ₀ , f ₂ The spectral shape of the spectrum SP _f2(2) (f, t) ^nc | _{i=1 to nw+1} is modified if an optimum value is obtained that clearly indicates the unfilled or filled grouting state.
Also, the maximum value of the cutout wave for analysis GB ₍₁₎ (t)| _i and the spectrum FB ₍₁₎ (f)| _i is normalized to 1.0 for each measurement point i.

Next, in the fourth analysis process, the maximum spectral value of the frequency lower than the frequency _fw in the spectrum for each analysis cutting wave of the spectrum FB ₍₁₎ (f) | _{i = 1 to nw + 1} described above is 1.0”, the spectral shape conversion process shown in FIG. _15C ( _hereinafter referred to as (called threshold processing) to obtain the primary spectrum for analysis FC _{( 1)} ( _f ) _| Find _nw+1 . Also, the primary time series for analysis GC ₍₁₎ | _i is displayed with the maximum value normalized to "1.0" for each of the measurement points i=1 to nw+1.

Note that the value of the threshold value α _σ will be selected from 0.5 to 0.75 in the analysis and study of a large number of sheath tubes in the future, and the time-swept normalized spectrum value SP _f2(2) (t)| _i , which will be described later, and when the spectral shape of the time-swept f ₀ , f _{2 spectrum} SP _{f2(2) (} f, t) ^nc | do.

_Next , the fifth analysis process applies a trapezoidal window function _A (see FIG. In the spectrum corresponding to the time series that is cut out by multiplying each time it moves from the _beginning of time t (=t _p(1) −Δt _p1 ) to _{the end of} time t (=t _p(1) +Δt _p2 ) at intervals of Δt _a , the frequency When the maximum spectral value occurring at f _w or less is normalized to "1.0", the maximum spectral value occurring at frequency f _w or more is defined as time sweep normalized spectrum value SP _f2 , and time sweep normalized spectrum value SP _{f2 ( 1)} (t)| _{i=1 to nw+1} (see FIGS. 16(b) and 20(a)) are created and displayed.

In addition, the spectrum obtained by comparing the maximum spectrum values generated at the frequency fw _or less and at the frequency fw _or more for each transition of time, and normalizing the larger spectrum value to "1.0" is the time sweep f ₀ , f ₂ spectrum, SP _{f2(1) (} f, t) ^nc | The exponent nc is a coefficient that allows SP _f2(1) (f, t) ^nc to be clearly divided between the void portion and the filled portion, and is set to nc=2 in this embodiment.
Note that the time sweep f ₀ , f ₂ spectrum SP _f2(1) (f, t) ^nc is represented by the maximum entropy method spectrum display (hereinafter referred to as MEM spectrum display).

_In addition, if the shape of the trapezoidal window function A described above is shown in _FIG . = "0.0" at _{the beginning of} t -5 and "1.0" at _{the beginning} of time t, time t = beginning of t to _{beginning of t} + _ta is "1.0", time t = t A sine-shaped decreasing function that becomes "1.0" at the _beginning + t _a and becomes "0.0" at time t = t _beginning + t _a +5, and a function that becomes "0.0" after time t = t _beginning + t _a +5 is.

Among the shape setting coefficients, the time t _a is shown in Table 2 for each of the primary cover thickness for analysis ds ₍₁₎ and the secondary cover thickness for analysis ds ₍₂₎ . Also, Δt _a =2 μsec.
Furthermore, Δt _p1 and Δt _p2 are approximate values of Δt _p1 =19 μs and Δt _p2 =82 μs, and the time sweep normalized spectrum value SP _f2(1) (t)| _i and the time sweeps f ₀ and f It enables the operator to set a value that facilitates confirmation of the shape of the change in the _2- spectrum SP _f2(1) (f, t) ^nc | _i . For example, in an analysis example (analysis example 1 in Table 3) to be described later, as shown in FIGS. 29A and 29B, the analysis primary reflected P-wave occurrence time t _p(1) =130. In the case of 1 μs, Δt _p1 is 11.2 μs and Δt _p2 is 94.4 μs.

Furthermore, among the reflected P wave, reflected M1 wave, and reflected _M2 wave of the cover thickness d2s of the second stage sheath, the plate thickness dw, or the path length dwc at the bottom corner of the plate thickness, t p ( _{1 )} −Δt _{p1 d2s , tM1 | d2s} , _tM2 | _{d2s ,} and tp _| dw, _tM1 | _{dw , tM2} | _dw can be displayed with a vertical cursor.

The occurrence times of these reflected waves are obtained by the above equations 4, 5, and 6, where the sheath reflected P-wave occurrence time _tp in the second stage is _changed to the reflected P-wave occurrence time _tp | Occurrence time _{tM1 of the second sheath} reflection _M1 wave is _the occurrence time _tM1 | _tM2 | _d2s , or replace the plate thickness reflected P wave occurrence time _tp with the reflected P wave occurrence time _tp | _dw , and the plate thickness reflected _M1 wave occurrence time _tM1 with the reflected _M1 wave The occurrence time t _M1 | _dw is obtained by replacing the occurrence time t _M2 of the plate thickness reflection _M2 wave with the occurrence time t _M2 | _dw of the reflection _M2 wave. The reflected wave from the path length dwc of the bottom corner of the stencil thickness is obtained in the same way.

次に、第６の分析処理（図２３のステップＳ１１２）で、時刻掃引基準化スペクトル値ＳＰ_{ｆ２（１）}（ｔ）｜_{ｉ＝ｎＡ～ｎＢ}の形状から特性ＴＡが選択され、空隙部分と充填部分との境界測点をｎ１と特定した場合（ステップＳ１１３：１）、第７の分析処理における特性ＴＡの処理（第１ＴＡ処理、及び第２ＴＡ処理）へ移行する。

Next, in the sixth analysis process (step S112 in FIG. 23), the characteristic TA is selected from the shape of the time sweep normalized spectrum value SP _f2(1) ( _t )| When n1 is specified as the boundary measurement point with the part (step S113: 1), the process proceeds to the characteristic TA process (first TA process and second TA process) in the seventh analysis process.

Alternatively, when the characteristic TB is selected in the sixth analysis process (step S112 in FIG. 23) and the boundary measurement point between the filled portion and the void portion is specified as n1 (step S113: 2), in the eighth analysis process The processing of the characteristic TB (first TB processing and second TB processing) is performed.

In general, the grout filling state is investigated at the end of the girder or side wall, and as described above as problem (3), the event that becomes the boundary between unfilled or insufficient filling and complete filling frequently occurs. do. Characteristic TA processing (first TA processing, second TA processing) and characteristic TB processing (first TB processing, second TB processing) are the processing flows for dealing with problem (3).

_{where the} characteristic TA is the time- _{swept normalized} spectral _{value SP} The value of _f2(1) (t)| _i=nA tends to increase with each increment of time t, and exceeds the threshold value _ασ at time _tp(1) + _ΔtB2 . It can be confirmed at measurement points i = nA to n1 (n1 ≤ nB) that the value of the integrated spectrum value SP _{f2 (1)} (t) | _i exceeds the threshold α _σ at time t _{p (1)} + Δt _B2 , And when n1 _{< nB} , the time sweep normalized spectrum value SP _{f2 (1) ( t} ) | Then, the boundary measurement point i=n1 between "unfilled or insufficiently filled" and "completely filled" of the sheath to be measured is specified.

On the other hand, _the characteristic TB is a time _- swept normalized spectrum value SP _f2 ( _{1 )} ( _t )| is below _σ , and the value of the time-swept normalized spectrum value SP _f2(1) (t)| _i is below the threshold α _σ at time t _p(1) +Δt _B2 . When it can be confirmed at i = nA ~ n1 (n1 ≤ nB) and n1 < nB, the time sweep normalized spectrum value SP _{f2 (1)} (t) _| There is an increasing tendency between _p(1) −Δt _B1 and time _{t p(1)} +Δt _B2 , and it is confirmed that the threshold α _σ is exceeded at time t _p(1) +Δt _B2 , and the sheath to be measured “ Identify the boundary station i=n1 between "fully filled" and "unfilled or underfilled".

Subsequently, the first TA process and the second TA process in the seventh analysis process (steps S114 to S116 in FIG. 24) will be described in detail.
In the first TA process (step S114 in FIG. 24) in the seventh analysis process, the time sweep normalized spectrum value SP _f2(1) (t) _| n1≦nB), there is an increasing trend between time t _p(1) −Δt _B1 and time t _p(1) +Δt _B2 where Δt _B1 =6 μs and Δt _B2 =12 μs, and time t _{p (1)} When _the threshold α _σ =0.5 is exceeded at +Δt _B2 , the time sweep normalized spectrum value SP _f2(1) (t) | Between t _p(1) −Δt _B1 and time t _p(1) +Δt _B2 , let t _i be the time when the threshold value α _σ is exceeded, and let t _A be the average value of this, or t _A in the case of single-point measurement. = t ₁ , Δt _A is obtained by the following equation 12, and the analysis secondary reflected P-wave occurrence time t _p(2) is specified by the following equation 13.

Secondary cover thickness for analysis ds ₍₂₎ is obtained by setting occurrence time _tp to analysis secondary reflected P-wave occurrence time _tp(2) in Equation 2, and sheath cover thickness ds to analysis secondary cover thickness ds ₍₂₎ .
In addition, the analysis secondary reflection P-wave occurrence time t _{p (2)} and the analysis secondary cover thickness ds ₍₂₎ are used to accurately and automatically specify the grout filling state at the target measurement point in the measurement target sheath. I am preparing.

ここで、式１３の係数０．３３は、多数の分析事例で特定したΔｔ_Ａに乗ずる値である。

Here, the coefficient 0.33 in Equation 13 is the value by which Δt _A specified in many analytical cases is multiplied.

After that, the analysis primary reflected P-wave occurrence time _tp(1) is changed to the analysis secondary reflection P-wave occurrence time _{tp( 2)} to create a secondary time series GC ₍₂₎ (t)| _{i=1 to nw+1 for} analysis instead of the primary time series GC for analysis ₍₁₎ (t)|

Next, in the second analysis process of _the fifth analysis process, the analysis secondary time series GC _{(2) (} t) | ₎ of the trapezoidal window function A using t _{p (2)} −Δt _p1 is the _starting point time t, and t _{p (2)} +Δt _p2 is the _ending point time t _{. (2)} (t)| _{i = 1 to nw+1} and the time sweep f ₀ , f ₂ spectrum SP _f2(2) (f, t) ^nc | _{i = 1 to nw+1} are created.

At this time, the control unit _{136 controls} the time sweep normalized spectrum value SP _{f2( 2 )} ( ^t )| _{i=1 to nw+1} (however, MEM spectrum display, nc=2) can be displayed on the display unit 135 upon receiving an operator's operation.

By the way, the summation average wave must be created using GC ₍₂₎ (t)| _i at measurement points i=nA to n1.
Therefore, the WAVE addition average wave GC ₍₂₎ ( _t ) |

さらに、上述のＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}のＦＦＴ変換でスペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を求め、式１５で、スペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を作成し、位相情報をスペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}のそれに変更し、この後、ＦＦＴ逆変換でＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}を作成する。なお、ＦＣ^～、及びＧＣ^～は、数式において、それぞれＦＣの上、ＧＣの上に“～”を付された符号を表す。

Further, the spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 described above, and the ^spectrum FC ₍₂₎ (f _{) | _} ^_ _{_ _ =nw+1} . Note that FC ^˜ and GC ^˜ represent the symbols with “˜” above FC and GC, respectively, in the formulas.

その後、第５の分析処理の再々度の台形窓関数Ａのｔ_ｐ（２）－Δｔ_ｐ１を始点時刻ｔ_始とし、ｔ_ｐ（２）＋Δｔ_ｐ２を終点時刻ｔ_終とする掃引処理に、上述のＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}、及び上述のＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}を適用し、分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）を用いて、ＷＡＶＥ加算とＳＰ加算との双方で時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝ｎｗ＋１}、及び時刻掃引ｆ_０，ｆ_２スペクトルＳＰ_{ｆ２（２）}（ｆ，ｔ）^ｎｃ｜_{ｉ＝ｎｗ＋１}を作成し直している。

After that, in the fifth analysis process, the sweep process with t _p(2) −Δt _p1 of the second trapezoidal window function A as the _start point time t and t _p(2) +Δt _p2 as the _end point time t is performed. Applying the WAVE averaged wave GC ₍₂₎ (t)| _{i=nw+1 and} the above-mentioned SP averaged wave GC ^~ ₍₂₎ (t)| Using t _p(2) , time-swept normalized spectral values SP _f2(2) (t)| _i=nw+1 and time-swept f ₀ , f ₂ spectra SP _{f2(2 )} (f,t) ^nc | _i=nw+1 .

At this time, _the control unit 136 controls the time _sweep normalized spectrum value SP _f2 ( _{2 )} (t)| f, t) ^nc | _i=nw+1 and time sweep f ₀ , f ₂ spectrum SP _{f2(2) (} f, t _* ) _{| i =1 to nw+1} can be displayed on the display unit 135 by accepting an operator's operation.

Next, using the time-swept normalized spectral values SP _f2(2) (t)| _{i=nA to n1} and the time-swept normalized spectral values SP _f2(2) (t)| _i=nw+1 , measuring points i=nA to n1, and at SP addition i=nw+1 are automatically determined by the following process.

Using the empty determination line segment α ^to _σ values and the empty determination cursor t _* =t _p(2) +*, the time sweep normalized spectrum value SP _f2(2) (t _{* )} | _i is obtained and set as SP _t* | _i , and the grout filling state is automatically determined as "unfilled" or "insufficient filling" based on the grout filling state determination formula shown in Equation 16 below. Note that the α ^to _σ values represent the sign with “~” added above α in the formula. The automatic determination result in the first TA process and the time-swept standardized spectral values SP _f2(2) (t)| _{i=1 to nw+1} are automatically displayed together on the display unit 135 .

ここで、空充判定線分α^～ _σ値は、閾値α_σ＝０．５を用いてα^～ _σ＝α_σ＋０．０６としている。空充判定カーソルｔ_＊＝ｔ_ｐ（２）＋＊の＊値は、多数シースの充填状態分析例により得た平均値であり、表２で分析用１次かぶり厚ｄｓ_（１）及び分析用２次かぶり厚ｄｓ_（２）ごとに設定している。

Here, _the value of the vacancy judgment line segment α ^∼ _σ is α ^σ =α _σ +0.06 using the threshold value α _σ =0.5. The * value of _the empty determination cursor t _* = t _{p (2)} + * is the average value obtained by the example of filling state analysis of multiple sheaths. It is set for each secondary cover thickness ds ₍₂₎ .

Using the starting measuring point nA and the ending measuring point nB for each sheath cover thickness pattern in Table 1 obtained in the first analysis process, when n1=nB (step S115 in FIG. 24: Yes), measuring point i=nA to nB Since the grout filling state at all measurement points has already been determined, after displaying the determination result on the display unit 135, the second TA process of the seventh analysis process is skipped, and all the processes end. Also in the case of single-point measurement, the second TA processing of the seventh analysis processing is skipped, and all processing ends.

In the first process, the primary cover thickness for analysis ds ₍₁₎ is a constant value "pattern (0)", and the reflected P-wave phase information of the measurement points i = nA to nB is the same. .

From this, in the first TA process, the grout filling state is the same analysis result (insufficient filling or unfilling) regardless of the time sweep normalized spectrum value SP _{f2 (2)} (t) | _{i = nw + 1} of SP addition and WAVE addition becomes. Although the primary cover thickness ds ₍₁₎ for analysis is the same value, if there is a slight difference, the phase of the sheath reflected P wave at the measurement point i = nA to n1 will change in WAVE addition. The amplitude of this wave is reduced.

From this, two time _- swept normalized spectrum values SP _f2(2) ( _t )| , _{f2 spectrum} SP _{f2(2) (} f, t) ^nc _| Two time sweeps f ₀ , f ₂ spectrum SP _f2(2) (f, _{t *} ) | .
On the other hand, if n1<nB (step S115 in FIG. 24: No), the process proceeds to the second TA process in order to determine the grout filling state at the measurement point i=n1+1 to nB.

The second TA process (step S116 in FIG. 24) in the seventh analysis process is applied only to multi-point measurement and is not automatically applied to single-point measurement _{. )} (t)| _i sets the threshold _{α σ} = 0.5 at time t _p(1) + Δt _B2 with Δt _B1 = 6 μs and Δt _B2 = 12 μs for each station i = n1 + 1 to nB time sweep normalized _spectrum value SP _{f2(1) ( t )} | is t _i , and the time t _i value of the measuring point i that satisfies the following equation 17 is selected.

ここでｔ_{Ｍ１（１）}は、上述の式４、式５、及び式６でシース反射Ｐ波起生時刻ｔ_ｐをｔ_ｐ（１）に、シース反射Ｍ_１波の起生時刻ｔ_Ｍ１をｔ_{Ｍ１（１）}に、シース反射Ｍ_２波の起生時刻ｔ_Ｍ２をｔ_{Ｍ２（２）}に置き換えて得るシース反射Ｍ_１波起生時刻ｔ_{Ｍ１（１）}≒（ｔ_ｐ（１）＋ｔ_ｐ（１）／０．６２）／２である。なお、係数０．６２は、一般的なコンクリートの横波音速Ｖ_ｓ／縦波音速Ｖ_ｐで求めている。
これら時刻ｔ_ｉの平均値を時刻平均値ｔ_Ａとして、次の式１８でΔｔ_Ａを求める。なお、式１７を満足させる時刻ｔ_ｉ値がない場合、時刻平均値ｔ_Ａ＝ｔ_{Ｍ１（１）}として、式１８でΔｔ_Ａを求める。

Here, _tM1(1) is the occurrence time _{tp (1)} of the sheath reflection P wave in Equations 4, 5, and 6 above, and the occurrence time _tM1 of the sheath reflection _M1 wave. Sheath reflection M ₁ wave occurrence time t _{M1 (1 )} ≈ (t _{p (1) + t p (1)} /0.62)/2. Note that the coefficient of 0.62 is obtained by the ratio of transverse wave sound velocity V _s /longitudinal wave sound velocity V _p of general concrete.
Assuming that the average value of these times t _i is the time average value t _A , Δt _A is obtained by the following equation 18. If there is no time t _i value that satisfies Equation 17, Δt _A is obtained by Equation 18 with time average value t _A =t _M1(1) .

分析用２次シース反射Ｍ_１波起生時刻ｔ_{Ｍ１（２）}を、次の式１９で求めている。

The analysis secondary sheath reflection _M1 wave occurrence time _tM1(2) is obtained by the following equation 19.

ここで、係数０．６５は、多数の分析結果より得た平均値である。
分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）は、次の式２０で算定される。

Here, the factor 0.65 is an average value obtained from a large number of analytical results.
The analytical secondary reflected P-wave occurrence time _tp(2) is calculated by the following equation 20.

式８の関係が分析用１次反射Ｐ波起生時刻ｔ_ｐ（１）の増減分量と、シース反射Ｍ_１波起生時刻ｔ_{Ｍ１（１）}の増減分量Δｔ_Ａとの関係でも成立することにより、次の式２１が成立する。

The relationship of Equation 8 is also established between the increase/decrease amount of the analysis primary reflection P-wave occurrence time _tp(1) and the increase/decrease amount _ΔtA of the sheath reflection _M1 wave occurrence time _tM1(1). Thus, the following formula 21 holds.

分析用２次かぶり厚ｄｓ_（２）は、式２のｔ_ｐを分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）に、式２のｄｓを分析用２次かぶり厚ｄｓ_（２）に置き換えて求めている。
なお、分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）、及び分析用２次かぶり厚ｄｓ_（２）は、計測対象シースの対象測点のグラウト充填状態を正確に自動特定するために準備している。
この後、第３の分析処理、及び第４の分析処理の再度の処理で、分析用１次反射Ｐ波起生時刻ｔ_ｐ（１）を分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）に置き換え、分析用１次時系列ＧＣ_（１）（ｔ）｜_{ｉ＝１～ｎｗ＋１}の代わりに、分析用２次時系列ＧＣ_（２）（ｔ）｜_{ｉ＝１～ｎｗ＋１}を作成する。

Analytical secondary cover thickness ds ₍₂₎ is obtained by setting t _p in Equation 2 to analytical secondary reflected P-wave occurrence time t _{p (2)} and ds in Equation 2 to analytical secondary cover thickness ds ₍₂₎ I'm looking for it instead.
In addition, the analysis secondary reflection P-wave occurrence time t _{p (2)} and the analysis secondary cover thickness ds ₍₂₎ are used to accurately and automatically specify the grout filling state at the target measurement point of the sheath to be measured. I am preparing.
After that, the analysis primary reflected P-wave occurrence time _tp(1) is changed to the analysis secondary reflection P-wave occurrence time _{tp( 2)} , and instead of the primary time series GC for analysis ₍₁₎ (t) | _{i=1 to nw+1} , create a secondary time series GC for analysis ₍₂₎ (t)| _{i=1 to nw+1} .

Next, in the processing of the fifth analysis processing again, the analysis secondary time series GC ₍₂₎ ( _{t )} | t _{p (2)} −Δt _p1 of the trapezoidal window function A _using , and t _{p (2)} + Δt _p2 as the _end point time t. SP _f2(2) (t)| _{i=1 to nw+1} and a time sweep f ₀ , f ₂ spectrum SP _f2(2) (f,t) ^nc | _{i=1 to nw+1} are created.

At this time, the control unit 136 controls the time sweep normalized ^spectrum value SP _{f2( 2 ) ( t} ) _{| =nw+1} ( _however , MEM spectrum display, nc= ₂ ) and time sweep f ₀ , f ₂ spectrum SP _{f 2 (2)} (f, t _* )| _{i=1 to nw+1} can be displayed on the display unit 135 upon receipt of an operator's operation.

By the way, the summation average wave must be created using GC ₍₂₎ (t)| _i at measurement points i=n1+1 to nB.
Therefore, the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 is recreated by the following equation 22.

さらに、上述のＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}のＦＦＴ変換でスペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を求め、次の式２３でスペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を作成し、位相情報をスペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}のそれに変更し、この後、ＦＦＴ逆変換でＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}を作成する。

Furthermore, the spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the above WAVE additive mean wave GC ₍₂₎ (t)| _i=nw+1 , and the ^spectrum FC ₍₂₎ ( f) Create | _{i=nw+1 ,} change the phase information to that ^of spectrum FC _{(2 )} (f)| Create _i=nw+1 .

次に、第５の分析処理の再々度の台形窓関数Ａのｔ_ｐ（２）－Δｔ_ｐ１を始点時刻ｔ_始とし、ｔ_ｐ（２）＋Δｔ_ｐ２を終点時刻ｔ_終とする掃引処理を、上述のＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}、及び上述のＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}に適用し、分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）を用いて、ＷＡＶＥ加算とＳＰ加算の双方で時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝ｎｗ＋１}、時刻掃引ｆ_０，ｆ_２スペクトルＳＰ_{ｆ２（２）}（ｆ，ｔ）^ｎｃ｜_{ｉ＝ｎｗ＋１}を作成し直している。

Next, the sweep processing with t _p(2) −Δt _p1 of the trapezoidal window function A of the fifth analysis processing as the _starting point time t and t _p(2) + Δt _p2 as the _ending point time t, Applied to the above WAVE averaged wave GC ₍₂₎ (t)| _{i=nw+1 and} the above-mentioned SP averaged wave GC ^~ ₍₂₎ (t)| Using time t _p(2) , time sweep normalized spectrum value SP _f2(2) (t)| _i=nw+1 for both WAVE addition and SP addition, time sweep f ₀ , f ₂ spectrum SP _f2(2) We are recreating (f, t) ^nc | _i=nw+1 .

At this time, _the control unit 136 _controls the time sweep normalized spectrum value SP _f2 ( _{2 )} (t)| f, t) ^nc | _i=nw+1 (however, MEM spectrum display, nc=2) can be displayed on the display unit 135 in response to an operator's operation.

After that, using the time-swept normalized spectral values SP _f2(2) (t)| i=n1+ _{1 to nB} and the time-swept normalized spectral values SP _f2(2) (t)| Automatically determine the grout filling state at each of the measurement points i=n1+1 to nB and at the SP addition i=nw+1.

Using the empty determination line segment α ^to _σ values and the empty determination cursor t _* =t _p(2) +*, the time sweep normalized spectrum value SP _f2(2) (t _{* )} | _i is obtained, SP _{t * |} are automatically displayed on the display unit 135 together with the time-swept standardized spectral values SP _f2(2) (t)| _{i=1 to nw+1} , and the analysis is completed.

At this time, as in the first TA process of the seventh analysis process, in the second TA process as well, the operator manipulates two time-swept standardized spectrum values SP _{f2(2 )} (t)| _{i=1 to nw+1} , two time sweeps f ₀ , f ₂ spectrum SP _f2(2) (f,t) ^nc | _i=nw+1 (where MEM spectral representation, nc=2), and empty two time sweeps f ₀ , f ₂ spectrum SP f _{2 (2)} ( _f , _{t *} ) | The presence or absence of the above-mentioned problem (4) can be confirmed.

Measurement points i = 1 to 4 and i = 5 (SP addition) by analysis of analysis example 3 (measurement points i = 1 to 4: complete filling) in Table 3 of "Threshold reflection P wave automated analysis case" described later is _shown in _FIG . 36(a).

Time-swept standardized spectrum value SP of empty-fill determination cursor t _* = _tp(2) + * (* = 16 in Table 2 from analysis secondary cover thickness ds ₍₂₎ = 201 mm in Analysis Example 3) When _f2 (t _* )| _{i=1 to 5,} it is automatically determined to be completely filled.
Note that the time sweep f ₀ , f _{2 spectrum} SP _f2(2) (f, t) ^nc | It is shown in FIG. 36(b). The SP summation will also show a fully packed shape.

Subsequently, the 1st TB processing and the 2nd TB processing in the eighth analysis processing (steps S117 to S119 in FIG. 24) will be described in detail.
In the first TB process (step S117 in FIG. 24) in the eighth analysis process, the time sweep normalized spectrum value SP _f2(1) (t)| _i is obtained from the measurement point i=nA ∼ n1 (n1≤nB), Δt _B1 = 6 μs, Δt _B2 = 12 μs, and when the threshold value α _σ = 0.5 is exceeded at time t _p(1) + Δt _B2 , time t _p(1) + Δt _Time -swept normalized spectrum value _{SP f2(1) ( t} ) | t _i =t ₁ ), and the average value of these is t _A. When there is no time t _i exceeding the threshold value α _σ , the primary reflection P Using the wave occurrence time t _p(1) , t _A =t _M1(1) in the same procedure as the second TA process in the seventh analysis process described above, the above equations 17, 18, 19, 20 and 21 are used to specify the secondary reflected P-wave occurrence time _tp(2) for analysis, and the occurrence time _tp is changed to the secondary reflected P-wave occurrence time _tp( In ₂₎ , the secondary cover thickness ds ₍₂₎ for analysis is obtained by replacing the sheath cover thickness ds with the secondary cover thickness ds ₍₂₎ for analysis.

After that, in the third analysis process and the second analysis process of the fourth analysis process, the analysis primary reflected P-wave occurrence time _tp(1) is changed to the analysis secondary reflection P-wave occurrence time _{tp(2 )} to create a secondary time series GC for analysis ₍₂₎ (t)| _{i=1 to nw+1} instead of the primary time series GC for analysis ₍₁₎ (t)| _{i=1 to nw+1} .

Next, in _the fifth analysis process, the analysis secondary time series GC ₍₂₎ (t ₎ | t _p(2) −Δt _p1 of the used trapezoidal window function A is the _starting point time t, and t p _{( 2)} +Δt _p2 is _{the ending} point time t. ₎ (t)| _{i=1 to nw+1} and the time sweep f ₀ , f ₂ spectrum SP _f2(2) (f,t) ^nc | _{i=1 to nw+1} .

At this time, the control unit _{136 controls} the time sweep normalized spectrum value SP _{f2( 2 )} ( ^t )| _{i=1 to nw+1} (however, MEM spectrum display, nc=2) can be displayed on the display unit 135 upon receiving an operator's operation.

By the way, the summation average wave must be created using GC ₍₂₎ (t)| _i at measurement points i=nA to n1.
Therefore, the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 is recreated by the following equation 14.

さらに、上述のＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}のＦＦＴ変換でスペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を求め、下記の式１５でスペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を作成し、位相情報をスペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}のそれに変更し、この後、ＦＦＴ逆変換でＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}を作成する。

Further, the spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the above WAVE additive mean wave GC ₍₂₎ (t)| _i=nw+1 , and the ^spectrum FC ₍₂₎ ( f) Create | _{i=nw+1 ,} change the phase information to that ^of spectrum FC _{(2 )} (f)| Create _i=nw+1 .

その後、第５の分析処理の再々度の台形窓関数Ａのｔ_ｐ（２）－Δｔ_ｐ１を始点時刻ｔ_始とし、ｔ_ｐ（２）＋Δｔ_ｐ２を終点時刻ｔ_終とする掃引処理に、上述のＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}、及び上述のＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}を適用し、分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）を用いて、ＷＡＶＥ加算とＳＰ加算の双方で時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝ｎｗ＋１}、及び時刻掃引ｆ_０，ｆ_２スペクトルＳＰ_{ｆ２（２）}（ｆ，ｔ）^ｎｃ｜_{ｉ＝ｎｗ＋１}を作成している。

After that, in the fifth analysis process, the sweep process with t _p(2) −Δt _p1 of the second trapezoidal window function A as _the start point time t and t _p(2) +Δt _p2 as the _end point time t is performed. Applying the WAVE averaged wave GC ₍₂₎ (t)| _{i=nw+1 and} the above-mentioned SP averaged wave GC ^~ ₍₂₎ (t)| Using t _p(2) , time- _swept normalized _spectral values SP _{f2(2) (} t ₎ | (f, t) ^nc | _i=nw+1 is created.

At this time, _the control unit 136 _controls the time sweep normalized spectrum value SP _f2 ( _{2 )} (t)| f, t) ^nc | _i=nw+1 (however, MEM spectrum display, nc=2) and time sweep f ₀ , f ₂ spectrum SP _f2 at the time of empty/empty determination cursor t _* =t _s(2) +* ₍₂₎ (f, t _* )| _{i=1 to nw+1} can be displayed on the display unit 135 upon receipt of an operator's operation.

Next, using the time-swept normalized spectral values SP _f2(2) (t)| _{i=nA to n1} and the time-swept normalized spectral values SP _f2(2) (t)| _i=nw+1 , at each station i=nA to n1 and at SP addition i=nw+1. Using the empty determination line segment α ^to _σ values and the empty determination cursor t _* =t _p(2) +*, the time sweep normalized spectrum value SP _f2(2) (t _{* )} | _i is obtained, this is SPt _* | _i , and based on the grout filling state determination formula of formula 16, the grout filling state is automatically determined as "complete filling", and the automatic determination result in this first TB process and the above-mentioned The time-swept standardized spectral values SP _f2(2) (t)| _{i=1 to nw+1} are automatically displayed together on the display unit 135 .

Two time-swept standardized spectrum values SP _f2(2) (t)| _{i=1 to nw+1} , two time-sweep f ₀ , _{f 2} spectrum SP _{f2(2) (} f, t) ^nc _| Two time sweeps f ₀ , f ₂ spectrum SP _f2(2) (f, _{t *} ) | .

Using the starting measuring point nA and the ending measuring point nB for each sheath cover thickness pattern in Table 1 obtained in the first analysis process, when n1=nB (step S118 in FIG. 24: Yes), measuring point i=nA Since the grout filling state at all nB measurement points has already been determined, after displaying the determination results on the display unit 135, the second TB process of the eighth analysis process is skipped, and all processes are terminated. Also in the case of single-point measurement, the second TB processing of the eighth analysis processing is skipped, and all processing ends.
On the other hand, if n1<nB (step S118 in FIG. 24: No), the process proceeds to the second TB process in order to determine the grout filling state at the measurement point i=n1+1 to nB.

The second TB processing (step S119 in FIG. 24) in the eighth analysis processing is applied only in the case of multi-point measurement, and is not automatically applied to single-point measurement _{. )} ( _{t)|i is time t p (1) −Δt B1 to time t p ( 1)} When there is an increasing trend between +Δt _B2 and exceeds the threshold value α _σ =0.5 at time t _p(1) +Δt _B2 , the time sweep normalized spectrum value SP _f2(1) (t)| _{i = n1 + 1 to nB,} the time when the threshold α _σ is exceeded between time t _{p (1)} - Δt _B1 and time t _{p (1)} + Δt _B2 is t _i , and the average value of time t _i for each measurement point i is determined, Δt _A is determined by Equation 12 above, and the analysis secondary reflected P-wave occurrence time t _p(2) is specified by Equation ₁₃ above.

The corresponding analytical secondary cover thickness ds ₍₂₎ is expressed by the expression 2 where the occurrence time t _p is the analytical secondary reflected P-wave occurrence time t _{p (2)} and the sheath cover thickness ds is the analytical secondary cover It is obtained by replacing the thickness ds with ₍₂₎ .
After that, in the third analysis process and the second analysis process of the fourth analysis process, the analysis primary reflected P-wave occurrence time _tp(1) is changed to the analysis secondary reflection P-wave occurrence time _{tp(2 )} to create a secondary time series GC for analysis ₍₂₎ (t)| _{i=1 to nw+1} instead of the primary time series GC for analysis ₍₁₎ (t)| _{i=1 to nw+1} .

Next, in _the fifth analysis process, the analysis secondary time series GC ₍₂₎ (t ₎ | t _p(2) −Δt _p1 of the used trapezoidal window function A is the _starting point time t, and t p _{( 2)} +Δt _p2 is _{the ending} point time t. ₎ (t)| _{i=1 to nw+1} and the time sweep f ₀ , f ₂ spectrum SP _f2(2) (f,t) ^nc | _{i=1 to nw+1} .

At this time, the control unit _{136 controls} the time sweep normalized spectrum value SP _{f2( 2 )} ( ^t )| _{i=1 to nw+1} (however, MEM spectrum display, nc=2) can be displayed on the display unit 135 upon receiving an operator's operation.

By the way, the summation average wave must be created using GC ₍₂₎ (t)| _i at measurement points i=n1+1 to nB.
Therefore, the WAVE addition average wave GC ₍₂₎ ( _t ) |

さらに、上述のＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}のＦＦＴ変換でスペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を求め、式２３でスペクトルＦＣ^～ _（２）（ｆ）｜_{ｉ＝ｎｗ＋１}を作成し、位相情報をスペクトルＦＣ_（２）（ｆ）｜_{ｉ＝ｎｗ＋１}のそれに変更し、この後、ＦＦＴ逆変換でＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}を作成する。

Furthermore, the spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the above WAVE addition average wave GC ₍₂₎ (t)|i _=nw+1 , and the ^spectrum FC ₍₂₎ (f) | _i=nw+1 is created, the phase information is changed to that of the spectrum FC ₍₂₎ (f)| _i=nw+1 , and then the SP addition average wave GC ^~ ₍₂₎ (t)| _i= Create _nw+1 .

次に、第５の分析処理の再々度の台形窓関数Ａのｔ_ｐ（２）－Δｔ_ｐ１を始点時刻ｔ_始とし、ｔ_ｐ（２）＋Δｔ_ｐ２を終点時刻ｔ_終とする掃引処理を、上述のＷＡＶＥ加算平均波ＧＣ_（２）（ｔ）｜_{ｉ＝ｎｗ＋１}、及び上述のＳＰ加算平均波ＧＣ^～ _（２）（ｔ）｜_{ｉ＝ｎｗ＋１}に適用し分析用２次反射Ｐ波起生時刻ｔ_ｐ（２）を用いて、ＷＡＶＥ加算とＳＰ加算との双方で時刻掃引基準化スペクトル値ＳＰ_{ｆ２（２）}（ｔ）｜_{ｉ＝ｎｗ＋１}、及び時刻掃引ｆ_０，ｆ_２スペクトルＳＰ_{ｆ２（２）}（ｆ，ｔ）^ｎｃ｜_{ｉ＝ｎｗ＋１}を作成し直している。

Next, the sweep processing with t _p(2) −Δt _p1 of the trapezoidal window function A of the fifth analysis processing as the _starting point time t and t _p(2) + Δt _p2 as the _ending point time t, Applied to the above-mentioned WAVE averaged wave GC ₍₂₎ (t)| _{i=nw+1 and} the above-mentioned SP averaged wave GC ^~ ₍₂₎ (t)| Using t _p(2) , time-swept normalized spectral values SP _f2(2) (t)| _i=nw+1 and time-swept f ₀ , f ₂ spectra SP _{f2(2 )} (f,t) ^nc | _i=nw+1 .

At this time, _the control unit 136 controls _the time-swept standardized spectrum values SP _{f2 (2) (} t)| (f, t) ^nc | _i=nw+1 (however, MEM spectrum display, nc=2) can be displayed on the display unit 135 upon receipt of an operator's operation.

After that, using the time-swept normalized spectral values SP _f2(2) (t)| i=n1+ _{1 to nB} and the time-swept normalized spectral values SP _f2(2) (t)| The grout filling state at each of the measurement points i=n1+1 to nB and at the SP addition i=nw+1 is automatically determined by the following processing.

Using the empty determination line segment α ^to _σ values and the empty determination cursor t _* =t _p(2) +*, the time sweep normalized spectrum value SP _f2(2) (t _{* )} | _i is obtained, SPt _* | _i , and based on the grout filling state determination formula of formula 16, the grout filling state is automatically determined as "unfilled" or "insufficient filling", and the determination result in this second TB process and the time-swept standardized spectral values SP _f2(2) (t)| _{i=1 to nw+1} are automatically displayed together on the display unit 135 .

At this time, as in the first TA process of the seventh analysis process, in the second TB process of the eighth analysis process as well, the operator operates two time sweep standardizations in which i=nw+1 is used for both WAVE addition and SP addition. Spectral value SP _f2(2) (t) | _{i=1 to nw+1} , two time sweeps f ₀ , f ₂ spectrum SP _f2(2) (f, t) ^nc | _i=nw+1 (where MEM spectral display, nc = 2), and two time sweeps f ₀ , f ₂ spectrum _{SP f2(2) (} f, t _* ) _| can be displayed for comparison, so that the presence or absence of the above-mentioned problem (4) can be confirmed.

Subsequently, in step S106 of FIG. 22, if it is not "pattern (0)" (step S106: Yes), the second process (step S108 in FIG. 22) and the third process (step S108 in FIG. 22) started by the analysis device 13 , step S109) will be described in detail.

When the sheath cover thickness patterns are "patterns (1) to (4)" and "patterns (1') to (4')" shown in FIG. Using the measurement point nB, the second processing with a _large primary fog thickness for analysis ds ₍₁₎ | and the third processing with a _small primary fog thickness for analysis ds ₍₁₎ | are sequentially performed. However, in the case of single-point measurement, these second and third processes are not performed because the analysis is performed in the first process.

First, the second process (step S108 in FIG. 22) is the same analysis flow as the first process shown in FIGS. 23 and 24, and its processing content is also the same as the first process .
However, in the second process, the analysis primary reflected P-wave occurrence time _tp(1) in the first process _is set to _{tp(1) | (1)} | _increased , secondary reflected P-wave occurrence time t _p(2) for analysis _increased to t _p(2) |, secondary cover thickness for analysis ds _{(2) increased} to ds ₍₂₎ | , sheath reflection _M1 wave occurrence time _{tM1(1) increased} to _tM1(1) |, secondary sheath reflection _M1 wave occurrence time _tM1(2) for analysis _increased to _tM1(2) | replace.

Also, the third process (step S109 in FIG. 22) has the same process flow as the first process shown in FIGS. .
However, in the third process, the analysis primary reflected P-wave occurrence time _tp(1) in the first process is _set to _{tp(1) | (1)} | to _small , secondary reflection P-wave occurrence time t _p(2) for analysis to t _p(2) | _small , secondary cover thickness for analysis ds ₍₂₎ to ds _{(2) |} , sheath reflection _M1 wave occurrence time _tM1(1) is reduced to _tM1(1) | _small , and analysis secondary sheath reflection _M1 wave occurrence time _tM1(2) is reduced to _tM1(2) | _small replace.

By the way, if the above-described problem (4) exists, the time-swept standardized spectrum value SP _f2(2) (t)| _{i =nw+1} is used to determine the state of grout filling, erroneously judging "unfilled" as "completely filled" or "insufficiently filled" often occurs.

FIG. 39(a) shows the time-swept normalized spectrum values SP _f2(2) ( _t )| .
In FIG. 39(a), No. 5 (=No. 1 + No. 2 + No. 3 + No. ₄ ) Time-swept standardized spectrum value SP _f2(2) (t) | 5 (=No. 1+No. 2+No. 3+No. 4) The time-swept standardized spectrum value SP _f2(2) (t)| _i=5 by WAVE addition is indicated by a dotted line.

FIG. 39(a) shows a sheath to be measured that has been confirmed to be "unfilled" by drilling, and an empty/filled determination cursor t _* = _tp(2) +* (however, analysis of analysis example 4 in Table 3 From the secondary cover thickness ds ₍₂₎ = 198 mm, at the time of * = 16) in Table 2, the SP addition (solid line) greatly exceeds the empty-filling judgment line segment α ^to _σ , and it is judged to be unfilled (correct). However, in the WAVE addition (dotted line), it slightly exceeds the empty/empty judging line segment α ^to _σ .

Looking at the sheath reflected wave generation situation shown in FIG. is occurring. It is shown that even a change of this degree in the sheath cover thickness due to problem (4) has an adverse effect on the determination of the grout filling state in the analysis by WAVE addition.

Here, a method for confirming the existence of problem (4) and a method for coping with it will be organized. First TA processing (step S114) and second TA processing (step S116) of the seventh analysis processing for each of the first processing (step S107), second processing (step S108), and third processing (step S109) , and in the first TB processing (step S117) and the second TB processing (step S119) of the eighth analysis processing, the analysis _secondary reflected P-wave occurrence time _tp(2) or _tp(2) | For each _small t _{p (2)} |, select a group of measurement points corresponding to the sheath to be measured, and perform the WAVE addition of Equation 14 above, the SP addition of Equation 15 above, or the WAVE addition of Equation 22 above, Time-swept _{normalized spectral} values SP _{f2(2) ( t} ⁾ _{| nw+1} is obtained by both WAVE addition and SP addition.

At this time, _the control unit 136 _controls the time sweep normalized spectrum value SP _f2 ( _{2 )} (t)| f, t) ^nc | _i=nw+1 (however, MEM spectrum display, nc=2) and time sweep f ₀ , f ₂ spectrum SP _f2 at the time of empty/empty determination cursor t _* =t _s(2) +* ₍₂₎ (f, t _* )| _{i=1 to nw+1} can be displayed on the display unit 135 upon receipt of an operator's operation.

Since the addition wave that obtains the correct answer is SP addition, in the automated processing, the grout filling state is analyzed using the time sweep normalized spectrum value SP _f2(2) (t)| _i=nw+1 (SP addition). there is
By the operator's operation, the grout filling state is analyzed using the grout filling state determination formula of Equation 16 even with the time sweep normalized spectrum value SP _{f2 (2)} (t) | _{i = nw + 1} (WAVE addition) using WAVE addition. Then, both filling states are compared as shown in FIG. 39(a) to confirm the presence or absence of problem (4). can be confirmed.

Such a comparison of analysis results is positioned as means for improving the analysis and examination ability of the operator in this threshold analysis. Note that if the adopted time-sweep normalized spectrum value SP _{f2(2) (} t _* ) | Due to the presence of point (4), "unfilled or insufficiently filled" is the correct answer, and in the case of "unfilled" in both SP addition and WAVE addition, "unfilled" is correct regardless of the presence or absence of problem (4). If the correct answer is "underfilling" or "unfilled" in both SP addition and WAVE addition, "underfilling" is the correct answer regardless of the presence or absence of problem (4), and SP addition In the case of "complete filling", WAVE addition always results in "complete filling" regardless of the presence or absence of problem (4).

<Case example of automatic analysis of threshold reflection P-wave>
The threshold reflected P-wave analysis along the analysis flow of FIGS. 22, 23 and 24 will be specifically described using sheath received waves selected from among many measured PC bridge sheaths.
The four sheaths shown in Table 3 below are examples of analyzes that address any of the four issues (1) to (4) described above, or a combination of the four issues (1) to (4). .

表３は、シース径欄が計測対象シースの直径（全てφ_ｓ３８）を示し、版厚欄、２段目シース欄、及びＲＣレーダ欄が、それぞれ分析を妨害する版厚ｄ_ｗ、２段目シースｄ_２ｓ、計測対象シースのレーダ計測かぶり厚ｄｓ｜_ＲＣを示している。さらに、削孔欄が削孔で確認した削孔かぶり厚ｄｓ｜_削、及びグラウト充填状態を示している。

In Table 3, the sheath diameter column shows the diameter of the sheath to be measured (all φ _s 38), and the plate thickness column, the second stage sheath column, and the RC radar column respectively indicate the plate thickness d _w that interferes with the analysis, and the two stages The eye sheath d _2s shows the radar-measured cover thickness ds| _RC of the sheath to be measured. Further, the hole drilling column shows _the hole cover thickness ds |

In addition, the primary cover thickness for analysis field contains the primary cover thickness for analysis ds ₍₁₎ (or ds ₍₁₎ | _large , and ds ₍₁₎ | _Small ). Furthermore, the analytical secondary fog thickness column indicates the analytical secondary reflected P-wave occurrence times t _p(2) (or t _p(2) | The analytical secondary cover thickness ds ₍₂₎ (or ds ₍₂₎ | _large and ds (2) | _{small )} for each station corresponding to large and t _{p (2)} | _small ) is shown.

Furthermore, the empty/filling determination column indicates the determination result of the grout filling state by the automatic analysis and the determination result of the grout filling state by the analysis operator, the white circle mark indicates "not filled", and the white triangle mark indicates "insufficient filling". , and the black circle indicates "completely filled".

<Analysis example 1>
Analysis example 1 is an analysis that addresses the four problems (1) to (4) described above. It should be noted that the sheath to be measured in Analysis Example 1 was confirmed to be "completely filled" by drilling a hole at an intermediate position between measurement point i=1 and measurement point i=2 under dense bar arrangement on the surface layer. .

In analysis example 1, through the first recording process (step S102) and the second recording process (step S103) in FIG. The spectrum and time series of (No. 1 + No. 2 + No. 3 + No. 4) are obtained.

Furthermore, in Analysis Example 1, the occurrence time t _p | _shaving (= 125.5 μsec) corresponding to the drilling cover thickness ds | _shaving (= 260 mm) obtained by drilling was separately obtained, The time series is multiplied by the time filter function TGC4(t), which is determined by Equation 1 using the _speed of sound V _p and has t _h = t _p | thick line) and the corresponding spectrum.

According to FIG. 28(b) obtained by multiplying the spectrum of FIG. 28(a) by the F3(f) filter function shown in FIG. At measuring point i = 1, _{the primary} reflected P-wave occurrence time tp _{( 1)} for analysis The average value of | _i becomes t _p(1) | _small , and the condition of the cover thickness of the sheath to be measured becomes "Pattern (1)" shown in FIG.

Primary _cover thickness ds ₍₁₎ | for analysis at measuring point i = 1 _Large and primary cover thickness ds _{( 1)} | _Small is the ds value obtained by applying the corresponding analytical primary reflected P-wave occurrence time t _p(1) | _large or t _p(1) | _small to the occurrence time t _p in Equation 2, respectively is.
In the analysis example 1, in the first analysis process, the central frequency _fs of the F3(f) filter function is changed from _fs = 80 kHz to _fs =82 kHz.

Next, in the second analysis process (step S105 in FIG. 22), the received wave (i=1 to 4) and the average wave (i=5, WAVE addition) spectrum (see FIG. 14(a)) Multiply the A _K (f) filter function to obtain the analysis spectrum FA(f)| _{i=1 to 5} and the analysis time series GA(t)| _{i=1 to 5} as shown in FIG. 14(b) ing.

First, the grout filling state at the measuring point i=1 of the primary cover thickness for analysis ds ₍₁₎ | _large (the primary reflection P-wave occurrence time t _{p(1) |} Since the sheath cover thickness pattern is "Pattern (1)" (step S106 in FIG. 22: Yes), the analytical time series GA( _t ) | The third analysis process, the fourth analysis process, and the fifth analysis process (step S111 in FIG. 23) in the process (step S108 in FIG. 22) are sequentially applied, and the primary reflection for analysis is applied in the third analysis process. P-wave occurrence _time t _{p (1)} | _Large cutout wave GB ₍₁₎ (t)| The spectrum FB ₍₁₎ (f)| _{i=1 to 5} is obtained by FFT transforming this wave.

Furthermore, a primary spectrum for analysis FC ₍₁₎ (f)| _{i=1 to 5} obtained by thresholding the spectrum FB ₍₁₎ (f)| _{i=1 to 5} in the fourth analysis process (FIG. 18 (b)) is inversely transformed by FFT to obtain the primary time series GC for analysis ₍₁₎ ( _t ) | Using _{large p(1)} |, time-swept normalized spectrum values SP _{f2 (1)} ( _t )| ₀ , f ₂ spectrum SP _f2(1) (f, t) ^nc | _{i=1 to 5} (not shown) is obtained. In addition, in the drawing, the notation of “| _large ” is omitted for clarity of illustration.
According to Table 1, since analysis example 1 is "pattern (1)", when _{the primary} cover thickness for analysis ds ₍₁₎ | The normalized spectral values SP _f2(1) (t)| _i=1 are shown in bold.

Next, in the sixth analysis process (step S112 in FIG. 23), the characteristic TA is selected according to the shape of the time-swept normalized spectrum value SP _f2(1) (t)| _i=1 , and n1=nB= 1 is specified.
The time-swept normalized spectrum value SP _f2(1) (t)| _i=1 tends to _increase sequentially from the _time t _p ( _{1 )} | , t _p(1) | _large +Δt _B2 exceeds the threshold value α _σ at B2, so this selection is made, and the process proceeds to the first TA process (step S114 in FIG. 24) of the seventh analysis process.

Time average value t A ₌ t 1 from the time sweep normalized spectrum value SP _f2(1) (t) | _{i=nA to n1} (where nA=1, n1=nB= ₁ ) in FIG. , Equation 12, and Equation 13, the _primary reflected P-wave occurrence time _tp(1) for analysis is set to tp _{( 1)} | Δt _A and the analytical secondary reflection P-wave occurrence time t p ₍₂ ) | _large are obtained by replacing with _p(2) | _large .

After that, in the third analysis process and the second analysis process of the fourth analysis process, the analysis _primary reflected P-wave occurrence time t _{p(1) | (2)} 1st _order time series GC for analysis ₍₁₎ (t)| 2nd order time series GC for analysis instead of _{i = 1 to 5 (2)} (t) | _{i = 1 to 5} , and then the time-swept normalized spectrum value SP _f2(2) (t)| _{i=1 to 5} and the time-swept spectrum SP _{f2 ( 2 )} (f, t) ^nc | _{i=1 to 5} are created and then displayed on the display unit 135 .

By the way, the addition average wave i=5 is the WAVE addition average wave GC ₍₂₎ (t)| _i=5 and the SP ^addition average wave GC ₍₂₎ (t)| _{i = both sides of 5} . Therefore, in the sweep processing of the trapezoidal window function A of the fifth analysis processing, the WAVE addition average wave GC ₍₂₎ (t)| _i=5 and the SP addition average wave GC ^~ ₍₂₎ (t) Applying | _i=5 , time-swept normalized spectral values SP _f2(2) (t)| _i=1˜5 and time-swept f ₀ , _f2 spectra SP _{f2( 2)} After recreating (f, t) ^nc | _i=5 , it is displayed on the display unit 135 .

In analysis example ₁ , by chance, _the secondary reflected P-wave occurrence time for analysis _{tp(2) |} Since the normalized spectrum value SP _f2(1) (t)| _i and the time sweep normalized spectrum value SP _f2(2) (t)| _i have substantially the same shape, FIG. time _- swept normalized spectral values SP _{f2 (2)} ( _t )| is used to determine the grout filling state at the measurement point i=1. Since nA=nB=1, the time-swept standardized spectrum values SP _f2(2) (t)| _i by SP addition and WAVE addition are the same, and the same analysis result is obtained.

According to the _above time- _swept standardized _spectrum value _{SP f2(2) ( t} )| However ^, from the _{analysis secondary} cover thickness ds ₍₂₎ | Therefore, since α ^~ _σ < SPt _* | _{i = 1, 5} < α ^~ _σ + 0.18 in the grout filling state determination formula shown in Equation 16, it is automatically determined as “insufficient filling” and the first TA process is terminated. . In addition, in FIG. 29(a), for the sake of clarity, the analysis primary reflected P-wave occurrence times _tp(1) and ds ₍₁₎ and the analysis secondary reflection P-wave occurrence time _{tp (2)} and ds ₍₂₎ omit the addition of “| _large ”.

In FIG. 29(a), vertical cursors indicated by white square marks indicate the second stage sheath reflection P-wave occurrence time _tp | _d2s . It can be confirmed that the second-stage sheath-reflected P-wave (thin solid line in the figure) at measuring points i=2 to 4 is generated near the second-stage sheath-reflected P-wave occurrence time t _p | _d2s .

The primary cover thickness for analysis ds ₍₁₎ | _large (=270 mm) and _the secondary cover thickness for analysis _{ds (2)} | P-wave occurrence times t _p(1) | _large and t _{p(2) |}
Also, FIG. 29(b) shows the time sweep f ₀ , f ₂ spectrum SP _{f 2 (2)} (f, t) ^nc | _i=1 (where MEM spectrum display, nc= 2) is illustrated.

After completing the first TA process of the seventh analysis process, since n1=nB (=1) (step S115 in FIG. 24: Yes), the analysis device 13 skips the second TA process of the seventh analysis process and , the second process is terminated, and the process proceeds to the third process (step S109 in FIG. 22) for analyzing the measurement points at which the primary fogging thickness for analysis ds ₍₁₎ | is _small .

This results in an analysis of the grout filling state at measuring points i=2, 3, and 4 where the primary cover thickness for analysis ds ₍₁₎ | _{is small} . In the third process, the analytical time series GA( _t ) | , and in the third analysis process, the analysis cutout wave GB using the analysis primary reflected P-wave occurrence time t _p(1) | _{small (1)} (t)| _{i=1 to 5} is obtained , corresponding spectra FB ₍₁₎ (f)| _i=1-5 .

Furthermore, in the fourth analysis _process , the spectrum FB _{( 1) (} f) | GC _{( 1 )} (t) _| In the time sweep processing by the window function A, the time sweep normalized spectrum value SP _f2(1) (t) | _{i=1 to 5} and the time sweep f ₀ , f ₂ spectrum SP _f2(1) ( f, t) ^nc | _{i=1 to 5} (not shown).

Next, in the sixth analysis process in the third process, the characteristic TB is selected according to the shape of the time-swept normalized spectral values SP _f2(1) (t)| _i=2-4 .
According to Table 1, since the analysis example 1 is "Pattern (1)", the start station nA=2 and the end station nB=4. _{Time -} swept normalized _spectrum value SP _{f2(1) ( t} ) _| Since nA to n1 (however, nA=2, n1=nB=4) can be confirmed, this selection is made, and the process proceeds to the first TB process (step S117 in FIG. 24) of the eighth analysis process.

According to the time-swept normalized spectral values SP _f2(1) (t)| _{i=nA to n1 in} FIG _. and time t ₄ satisfies Equation 17, Δt _A is calculated by Equation 18 with the time average value t _A as the average value of time t ₂ and time t ₄ . Here, the sheath reflection _M1 wave occurrence time t _M1(1) shown in Equations 17, 18, and 19 is t _M1(1) ≈(t _p(1) +t _p(1) /0.62 )/2.

Furthermore, the analytical secondary sheath reflection _M1 wave occurrence time t _M1(2) obtained by Equation 19 is set to t _M1(2) | _small , and the analytical primary reflection P wave occurrence time t _{p(1 )} , and the analysis secondary reflected P-wave occurrence time t _p(2) are replaced by t _p(1) | _small and t _{p(2) |} Time t _p(2) | _small is sought. Note that the increment/decrement amount Δt in Equation 20 is calculated by Equation 21.

The _secondary reflection P-wave occurrence time _{tp (2) | for} analysis is set to 2 Next _fogging thickness ds ₍₂₎ |
According to FIG. 30(a), the analytical primary fog thickness ds ₍₁₎ | _small (=230 mm), the analytical primary reflected P-wave occurrence time t _p(1) | _small (=111.8 μsec). , the analytical secondary fog thickness ds ₍₂₎ | _small (=221 mm), and the analytical secondary reflected P-wave occurrence time t _p(2) | _small (=107.8 μsec).

Next, by applying the analytical _secondary reflected P-wave occurrence time t _p(2) | , the time-swept normalized spectral values SP _f2(2) (t)| _{i=1 to 5} shown in FIG. 30(b). Note that the time sweep standardized spectrum value SP _f2(2) (t)| _i=5 and the time sweep f ₀ , f ₂ spectrum SP _f2(2) (f, t) ^nc | _i=5 is recreated by both WAVE summation of stations i=2,3,4 and SP summation.

Furthermore, _using the time-swept normalized spectral values SP _f2(2) (t) | 4 grout filling state is automatically determined.
Empty determination cursor t _* = _tp(2) +* (however, *=18 in Table 2 from secondary fog thickness for analysis ds ₍₂₎ =221 mm) at the time of time sweep standardized spectrum value SP _{f2( 2)} (t) | _{i = 2, 3, 4} is much lower than the line segment α ^~ _σ = α _σ + 0.06 (= 0.56) for judging emptyness, so based on the grout filling state judgment formula of formula 16 Then, the grout filling state at the measurement points i=2, 3, 4 is automatically determined as "complete filling", and the first TB processing of the eighth analysis processing ends.

FIG. 31 shows the time sweep f ₀ , f ₂ spectrum SP _{f 2 (2)} (f, t) ^nc | _i=5 (where MEM spectrum representation, nc=2).
In addition, in FIGS. 30A and 30B, for clarity of illustration, the primary reflection P-wave occurrence times for analysis t _p(1) , ds ₍₁₎ , the secondary reflection for analysis P The wave occurrence times t _p(2) and ds ₍₂₎ omit the addition of “| _small ”.

In the analysis example 1, when the first TB process of the eighth analysis process is completed, the grout filling state does not change in the secondary cover thickness for analysis ds ₍₂₎ | _small cover thickness, in other words, n1=nB Since (=nw=4) (step S118 in FIG. 24: Yes), the analysis device 13 skips the second TB process of the eighth analysis process and ends all the processes.

In FIGS. 30(a) and 30(b), the second sheath reflection P wave occurrence time _tp | _d2s is automatically displayed with a vertical cursor, and the second sheath reflection P wave is the sheath reflection P It shows how it does not mix on the waves. The second-stage sheath reflection P-wave occurrence time t _p | _d2s is obtained by replacing the sheath cover thickness ds in Equation 4 above with the second-stage sheath cover thickness d2s input in the input reception process (step S101). ing. Similar measures are taken in FIGS. 38(b), 39(a), and 39(b) of Analysis Example 4, which will be described later.

<Analysis example 2>
For the sheath to be measured used in Analysis Example 2, it has been confirmed that the grout filling state is "unfilled (empty)" at the drilling of measurement point i=1. As shown in the order of FIGS. 14, 15, 16, and 17, the sheath to be measured was subjected to a series of analyzes with the sheath cover thickness set to the same value. It is the same sheath whose status is being analyzed as "unfilled (empty)".

In the series _{of analyses} , the radar-measured cover thickness ds| However, this is an erroneous determination due to problems (3) and (4). Correctly, it is the measurement at the grout filling state boundary position where the measuring points i = 1 and 2 are "unfilled" and the measuring points i = 3 and 4 are "completely filled".

Specifically, in analysis example 2, after going through the first recording process (step S102) and the second recording process (step S103) in FIG. 22, the frequency of the first analysis process (step S104) in FIG. By analysis (see FIGS. 26(a) and 26(b)), the analysis primary reflected P-wave occurrence times t _p(1) | _{i=1 to 4} in FIG. The primary cover thickness for analysis ds ₍₁₎ | _{i=1 to 4} is obtained by Equation (2).

In analysis example 2, the primary cover thickness for analysis at measuring points i = 1 and 2 is ds ₍₁₎ | _large = 271 mm, the primary cover thickness for analysis at measuring points i = 3 and 4 _is ds ₍₁₎ | This is an analysis example of "Pattern (2)" shown in FIG. 27 with 244 mm.
In the first analysis process, the center frequency f _s of the F3(f) filter function is sequentially moved from f _s =80 kHz to f _s =100 kHz by the operation of the operator. _{Fog thickness ds (1 ) |} The time t _p(1) | _small ) is obtained with high accuracy.

Next, in the second analysis process (step S105), A _K (f) A filter function is multiplied to obtain an analysis spectrum FA(f)| _{i=1 to 5} and an analysis time series GA(t)| _{i=1 to 5} (see FIG. 14(b)).

First, the grout filling state of _{the primary} cover thickness for analysis ds ₍₁₎ | In the second process (step S108), the analysis time series GA( _t ) | 5 analysis processing is sequentially applied, and in the same processing flow as in Analysis Example ₁ , the time sweep _reference shown in FIG. obtained _spectral ^values SP _{f2(1) ( t ) |} ing.

However, the time-sweep normalized spectrum value SP _f2(1) (t)| _i=5 in FIG _. It is calculated and displayed using the WAVE addition result of _{i=1, 2} . Since there is no phase shift in the waves with i=1 and 2 in FIG. 32(a), the result of SP addition and the result of WAVE addition are the same.
Next, in the sixth analysis process (step S112), the characteristic TA is selected according to the shape of the time-swept normalized spectral value SP _f2(1) (t)| _i=1,2 , and the boundary station n1= 2.

Since analysis example 2 is "pattern (2)", from Table 1, the start station nA=1 and the end station nB=2. Time sweep normalized spectrum value SP _f2(1) (t) | Time _{t p(1)} | _Large -Δt _B1 to time t _p where _{i = 1 to 2} are Δt _B1 = 6 µs and Δt _B2 = 12 µs ₍₁₎ There is an increasing trend between | _large + Δt _B2 , and the _number of measurement points exceeding the threshold value α _σ at time t p _{( 1)} | = 2), this selection is made, and the process proceeds to the first TA process (step S114) of the seventh analysis process.

Time-swept normalized spectrum value SP _f2(1) (t) | _{i=nA to n1} (where _n1 =nB= ₂ ) in FIG _. 2, the analysis primary reflected P-wave occurrence time _tp(1) in Equations 12 and 13 _{is increased} to _tp(1) |, and the analysis secondary reflected P-wave occurrence time _{tp(2 )} is replaced with t _p(2) | _large to obtain Δt _A and the analysis secondary reflection P-wave occurrence time t _p(2) | _large .

Next _, the analysis primary reflection P-wave occurrence time t _p(1) | P _{- wave} occurrence time t p _{( 2)} | _As in Analysis Example 1, also in Analysis Example 2, by chance, the occurrence time of the primary reflected _P -wave for analysis tp( _{1 )} | , the time-swept normalized spectral value SP _f2(1) (t)| _i and the time-swept normalized spectral value SP _f2(2) (t)| _i have substantially the same shape.

For this reason, the second processing of the fifth analysis processing is omitted, and the time sweep normalized spectral value SP _f2(1) (t)| _i in _{FIG. 2)} (t) | _i (= SP _{t *} | _{i = 1, 2} ) is applied to the grout filling state determination formula of Formula 16, and the grout filling state at the measurement point i = 1, 2 is "unfilled ( Empty)” is automatically determined, and the first TA process ends.

Fig. 33(a) shows the time sweep _{f0 , f2} spectrum SP _f2(2) (f, t) ^nc | ) is displayed.
Note that the time-sweep normalized spectrum value SP _f2(2) (t)| _i=5 in FIG. there is Originally, the procedure for the subsequent analysis is to use the time-swept standardized spectrum value SP _f2(2) (t) | _i=5 by SP addition, but for the following reasons, Analysis is performed using time-swept normalized spectral values SP _f2(2) (t)| _i=5 of WAVE summation.

Since the analysis primary reflected P-wave occurrence time t _p(1) | ₁ and the analysis primary reflected P-wave occurrence time t _p(1) | ₂ in FIG. No phase shift occurs in the sheath-reflected P-waves with i=1 and 2. As a result, both WAVE addition and SP addition result in correct answers.
In addition, in FIG. 32(b), for clarity of illustration, the secondary reflection P-wave occurrence time t _p(2) for analysis and ds ₍₂₎ are omitted from the addition of “| _large ”. .

Since the above analysis results in n1=nB=2 (step S115: Yes), the second TA process of the seventh analysis process is skipped, the second process is terminated, and the primary cover thickness for analysis ds _{( 1)} Move to the third process (step S109) for analyzing measurement points i=3 and 4 where | is _small .

In the third process, the analytical time series GA( _t ) | are sequentially applied, and the measurement points i = 3 and 4 are analyzed using the analysis primary reflected P-wave occurrence time t _{p (1)} | _small in the same processing flow as in Analysis Example 1 33( _b ) time _- swept normalized _spectrum values SP _f2 ⁽ _{1 )} (t)| _{~ 5} (not shown) is sought.

Next, in the sixth analysis process (step S112), the characteristic TB is selected according to the shape of the time-swept normalized spectral value SP _f2(1) (t)| _{i=3, 4} , and n1=nB=4 is identified. According to Table 1, the analysis example 2 is "pattern (2)", and the start station nA=3 and the end station nB=4 in the third process.

Time _- swept normalized _spectral value _{SP f2 ( 1 )} (t)| (However, nA=3, n1=nB=4) can be confirmed, so this selection is made, and the process proceeds to the first TB process (step S117) of the eighth analysis process.

Time-swept normalized spectral values SP _f2(1) (t) | _{i=nA to n1} (where n1=nB) in _FIG . ₄ satisfy Expression 17. Therefore, the time average value t _A is the average value of time t ₃ and time t ₄ , Δt _A is calculated by Equation 18, and the secondary sheath reflection for analysis M ₁ wave occurrence time t _{M1 (2 ) |}

Furthermore, using Equations 20 and 21, the amount of increase or decrease from the primary reflected P-wave occurrence time for analysis t _p(1) | _small to the secondary reflected P-wave occurrence time for analysis t _p(2) | _small Δt and the analysis secondary reflected P-wave occurrence time t _p(2) | _small are calculated. Analyzing secondary cover thickness ds ₍₂₎ | _small is the occurrence time _tp of Equation 2 to the analysis secondary reflected P-wave occurrence time _tp(2) | _small , and the sheath cover thickness ds is changed to analysis 2 Next _fogging thickness ds ₍₂₎ |

According to FIG. 33(b), the analytical primary fog thickness ds ₍₁₎ | _small (=244 mm), the analytical primary reflected P-wave occurrence time t _p(1) | _small (=118.2 μsec). , the analytical secondary fog thickness ds ₍₂₎ | _small (=229 mm), and the analytical secondary reflected P-wave occurrence time t _p(2) | _small (=111.2 μsec).

Next, in the continuous processing of the third analysis processing, the fourth analysis processing, and the fifth analysis processing using the analysis secondary reflection P-wave occurrence time t _p(2) | _small , FIG. SP _f2 (t) | _{i = 1 to 5} (i = 5 is SP addition of i = 3 and 4, i = 3, 4 and 5 are shown by thick solid lines) shown in (a) After that, in the second processing of the fifth analysis processing, create the time sweep normalized spectrum value SP _{f2 (2)} ( _t ) | Then, the time-swept normalized spectrum values SP _f2(2) (t)| _{i=3, 4} and the SP-added time-swept normalized spectrum values SP _f2(2) (t)| _i=5 are , is applied to the grout filling state determination formula of formula 16, the grout filling state at i=3, 4, 5 is automatically determined as "complete filling", and the first TB processing of the eighth analysis processing ends.

FIG. 34(b) shows the time sweep f ₀ , f ₂ spectrum SP _{f 2 (2)} (f, t) ^nc | _i=5 (but MEM spectral display, nc=2) is shown.
In addition, in FIG.33(b) and FIG.34(a), in order to clarify illustration, _tp(1) , ds ₍₁₎ , _tp(2) , ds ₍₂₎ , _tM1(1) , and t _M1(2) , the addition of “| _small ” is omitted.

When the first TB processing of the eighth analysis processing is completed, the measurement points i=3 and 4 where _{the primary} cover thickness for analysis ds ₍₁₎ | Since the filling state has been determined, the second TB processing of the eighth analysis processing is skipped, and all processing ends.

<Analysis example 3>
The sheath to be measured used in Analysis Example 3 is confirmed to be "completely filled" at the drilling of measurement point i=1.
In the first analysis process of FIG. 22, the operator manipulates the _cover thickness ds| for _drilling instead of the cover thickness ds| _RC measured by the radar, and the occurrence time t _p | By frequency analysis and time-series processing by the time filter function TGC4(t) (see FIGS. 26(a) and 26(b)), it corresponds to the primary reflected P-wave occurrence time _tp(1) for analysis. The primary cover thickness for analysis ds ₍₁₎ is obtained as shown in FIG. 35(a). The cover thickness is substantially the same in the longitudinal direction of the sheath, forming "pattern (0)" (see FIG. 27).
In the analysis example 3, in the first analysis process, the center frequency f _s of the F3(f) filter function is moved from f _s =80 kHz to f _s =96 kHz by the operation of the operator.

The analytical primary reflection P-wave occurrence time _tp(1) is 97.5 μs, and the corresponding analytical primary cover thickness ds ₍₁₎ is obtained by multiplying the occurrence time _tp of Equation 2 by the analytical primary reflection. At the P-wave occurrence time _tp(1) , the sheath cover thickness ds is replaced with the analysis primary cover thickness ds ₍₁₎ to be 194 mm. Since the drilling cover thickness ds | _is 236 mm, there is a difference of 42 mm between the primary cover thickness ds ₍₁₎ for analysis and _the drilling cover thickness ds | It is determined that the measurement position and the drilling position are different. If the hole _cover thickness ds |

In the second analysis processing, which is the same as the analysis examples 1 and 2 described above, using the A _K (f) filter function, the analysis spectrum FA (f) | _{i = 1 to 5} and the analysis time series GA (t ) | _{i = 1 to 5} , then in the first process, a third analysis process using the analysis primary reflected P-wave occurrence time t _{p (1)} , a fourth analysis process, and a 5 analysis processing is applied sequentially, and in the same processing flow as analysis examples 1 and 2, the time sweep normalized spectrum values SP _f2(1) (t) | _{i = 1 to 5} and A time sweep f ₀ , f ₂ spectrum SP _f2(1) (f, t) ^nc | _{i=1 to 5} (not shown) is obtained.

Next, in the sixth analysis process, the characteristic TB is selected from the shape of the time-swept normalized spectral values SP _f2(1) (t)| _{i=1 to 4} , and n1=nB=4 is specified. .
Since analysis example 3 is "pattern (0)", from Table 1, the start station nA=1 and the end station nB=4. Time _{- swept} normalized spectrum value SP _{f2(1) ( t} ) _| Since it can be confirmed that nA=1, n1=nB=4), this selection is made, and the process shifts to the first TB process of the eighth analysis process.

Time sweep normalized spectrum value SP _f2(1) (t) | _{i=nA to n1 (} where n1=nB= ₄ ) in FIG. Since time t ₃ and time t ₄ satisfy Equation 17, Δt _A is calculated by Equation 18 using the time average value t _A as the average value of these times t _i .

Furthermore, the analytical secondary sheath reflection _M1 wave occurrence time _tM1(2) is calculated using Equation 19, and the analytical primary reflection P wave occurrence time _tp(1) is calculated using Equations 20 and 21. to the analysis secondary reflection P-wave occurrence time tp ₍₂₎ , and calculate the analysis secondary reflection P-wave occurrence time _tp(2) = _tp(1) + Δt. there is

Next, the analysis primary reflected P-wave occurrence time _tp(1) is changed to the analysis secondary reflected P-wave Time _- swept normalized _spectrum values SP _{f2(2) ( t )} | t) ^nc | _{i = 1 to 5} are created, and time-swept normalized spectral values SP _f2(2) (t) | _{i = 1 to 5} and the time sweep f ₀ , f ₂ spectrum SP _f2(2) (f, t) ^nc | _i=5 are recreated and displayed on the display unit 135 .

Time-swept normalized spectral values SP _f2(2) (t _* ) | _{i = 1 to 4} (=SP _t* | _{i = 1 to 4} ) and time-swept normalized spectral values of SP addition in Fig. 36(a) By applying SP _f2(2) (t _* ) | _{i = 5} (=SP _t* | _{i = 5} ) to the grout filling state determination formula of formula 16, measuring points i = 1, 2, 3, 4 and i=5 SP addition waves automatically determine the grout filling state.

_{The time} -swept standardized spectral _values SP _{f2(2) (} t) | ₂₎ From = 201 mm, from Table 2, * = 16), since it falls below the line segments α ^to _σ for determining whether there is empty, the grout filling state at measuring points i = 1 to 4 is judged to be "complete filling". , ends the first TB processing of the eighth analysis processing.

When the first TB processing of the eighth analysis processing is completed, the analysis equipment 13 has nA = 1 and n1 = nB (= 4), so in other words, the analysis determination of the grout filling state at all measurement points has been completed, the second TB processing of the eighth analysis processing is skipped, and all processing ends.

Note that in this analysis example 3, the sheath reflection P-wave occurrence time _t corresponding to the radar-measured cover thickness _ds | or the sheath reflection P-wave occurrence time t _p | corresponding to _{the drilling cover thickness ds} | _{i=1 to 5} are shown in FIG. 37(a). Both the radar-measured cover thickness ds| _RC and _the drilled cover thickness _ds | The SP _f2 spectrum of the sheath reflection _M1 wave of the sheath to be measured, which is indicated by the mark, is large, and it is erroneously determined as "unfilled (empty)".

FIG. 37(b) shows the time sweep f ₀ , f ₂ spectrum SP _{f 2 (cut)} (f, t) ^nc | _i=5 (where SP addition, MEM spectrum display, nc=2 ). Due to the above-mentioned problem (1), when the sheath cover thickness or the concrete longitudinal wave sound velocity is misidentified and the cutout wave for analysis is obtained, and the grout filling state is analyzed using this, "complete filling (filling sheath)" is changed to "not complete filling (filling sheath)". Filling (empty sheath)” is erroneously determined.

Depending on the PC bridge to be measured, problem (1) (misidentification of dielectric constant of concrete and sound velocity value) may occur significantly in all sheaths to be measured. From this, if the first analysis process is omitted, the correct time-swept standardized spectrum values SP _f2(2) ( _t )| , and correct _time sweep f ₀ , f ₂ spectrum SP _f2(2) (f, t) ^nc |

<Analysis example 4>
The sheath to be measured used in Analysis Example 4 is a beam model for analysis and is confirmed to be "unfilled (empty sheath)".
In the first analysis process of FIG. 22, the time-series wave G(t)| _{i=1 to nw} obtained by multiplying the received wave spectrum F(f)| _{i=1 to nw} by the F3(f) filter function (where nw=4) is multiplied by the time filter function TGC4(t) using the radar-measured fog thickness ds| _RC as an index (see FIGS. 26(a) and 26(b)). The analysis primary reflected P-wave occurrence time _tp(1) is obtained, and the corresponding analysis primary cover thickness ds ₍₁₎ is obtained from Equation (2).
In Analysis Example 4, in the first analysis process, the center frequency f _s of the F3(f) filter function is moved from f _s =80 kHz to f _s =96 kHz by the operator's operation.

The covering thickness hardly changes in the longitudinal direction of the sheath, which is "Pattern (0)" (see FIG. 27).
At measurement points i=1 to 4, the primary cover thickness for analysis ds ₍₁₎ =194 mm is substantially the same, and the difference from the radar-measured cover thickness ds| _RC =215 mm is 21 mm.

Next, in the same second analysis processing as in the analysis examples 1, 2, and 3 described above, the analysis spectrum FA(f) | _{i=1 to 5} and _the analysis time Create a sequence GA(t)| _i=1-5 . After that, by "pattern (0)" (see FIG. 27), in the first process (step S107), the third analysis process, the fourth analysis process, and the fifth analysis process are sequentially applied, Analytical clipping wave GB ₍₁₎ ( _t )| _{i=1 to 5} and spectrum FB ₍₁₎ (f ) _|

Furthermore, the primary spectrum for analysis FC ₍₁₎ (f) | _{i = 1 to 5} and the primary time series for analysis GC ₍₁₎ (t) | _{i = 1 to 5} is obtained, _and the time-swept standardized spectrum value shown in FIG. SP _f2(1) (t) | _{i=1 to 5} (WAVE addition) and time sweep f ₀ , f ₂ spectrum SP _f2(1) (f, t) ^nc | _{i=1 to 5} (not shown) Seeking.

Next, in the sixth analysis process, the characteristic TA is selected according to the shape of the time-swept standardized spectrum value SP _f2(1) (t)| _{i=1 to 4} in FIG. identified. According to Table 1, since it is "pattern (0)", the start station nA=1 and the end station nB=4.

_{Time - swept} normalized spectral _values SP _{f2(1) ( t} )| +Δt _B2 , and the number of measurement points i exceeding the threshold value α _σ at time t p _{( 1)} +Δt _B2 can be confirmed as i = nA to n1 (where n1 = nB = 4), This selection is made, and the process moves to the first TA process of the seventh analysis process.

Time sweep normalized spectrum value SP _f2(1) (t) | _{i=nA to n1} (where nA= ₁ , n1=nB= ₄ ) in FIG. After selecting t ₄ and obtaining the time average value t _A = (t ₂ + t ₃ + t ₄ ) / 3, Δt _A is obtained by Equation 12, and the secondary reflected P-wave occurrence time for analysis is calculated by Equation 13. We are looking for _tp(2) .
The corresponding analysis secondary cover thickness ds ₍₂₎ is obtained by changing the occurrence time _tp of Equation 2 to the analysis secondary reflected P-wave occurrence time _tp(2) and the sheath cover thickness ds to the analysis secondary cover. It is obtained by replacing with the thickness ds ₍₂₎ .

Next, the analysis primary reflection P-wave occurrence time _tp(1) is changed to the analysis secondary reflection P The wave occurrence time is changed to t _p(2) , and the time sweep standardized spectrum values SP _f2(2) | _{i=1 to 5} shown in FIG. 39(a) are created.

By the way, the summation average wave i=5 can be obtained from the WAVE summation average wave GC ₍₂₎ (t)| _i=5 and the SP summation average wave ^GC ₍₂₎ (t)| _{i = both sides of 5} . For this reason, the above-described WAVE addition average wave GC ₍₂₎ (t)| _i=5 and SP addition average wave GC ^~ ₍₂₎ ( t) apply | _i=5 , time _- swept scaled spectral values SP _{f2(2) for} both WAVE and _SP summation ( _t )| ₍₂₎ (f, t) ^nc | _i=5 (not shown) is recreated and displayed on the display unit 135 .

Using these time-swept normalized spectrum values SP _{f2(2) (} t)| are doing.
Time-swept standardized spectrum value at the time when the empty-fill judgment cursor t _* = _tp(2) + * (* = 16 in Table 2 from the secondary cover thickness ds ₍₂₎ = 198 mm for analysis in Table 3) SP _f2(2) (t _* ) | _{i = 1 to 5} greatly exceeds the line segment α ^to =α _σ +0.06 (= 0.56) for judging emptyness, so the grout filling state judgment formula of formula 16 Based on this, the grout filling state at the measurement points i=1 to 4 is automatically determined as "unfilled", and the first TA process of the seventh analysis process ends.

Fig. 39(a) shows time-swept standardized spectra for both WAVE addition (dotted line in the figure) and SP addition (solid line in the figure) by averaging (No. 1 + No. 2 + No. 3 + No. 4) of i = 5 The value SP _f2(2) (t)| _i=5 is shown. Around the time of the empty/empty determination cursor t _* = _tp(2) +*, it becomes small with WAVE addition and large with SP addition. This is a phenomenon caused by a half-wave shift between the phase information of the sheath reflected wave at i=1 and the phase information of the sheath reflected waves at i=2, 3, and 4 in FIG. The correct answer is "unfilled (empty)" as a result of the addition analysis.

Note that FIG. 39(b) shows the time sweep f ₀ , f ₂ spectrum SP _f2(2) (f, t) ^nc | _i=5 (where MEM spectrum display, nc=2) in SP addition. . It can be confirmed that the reflected P wave of the second stage sheath ("stage 2P" in the figure) is generated after the time.

When the first TA process of the seventh analysis process ends, the analysis equipment 13 determines that the grout filling state at all measurement points i = 1 to 4 is "unfilled" in the first TA process, so the second TA process is performed. Skip and end all processing.

<Verification of validity of threshold reflection P-wave analysis method>
The threshold reflectance P-wave analysis method was detailed using several measured sheaths with known grouting conditions.
Using the received wave G(t) | _{i = 1 to 4} of sheath reflected P wave measurement selected from a large number of sheaths to be measured recorded on many existing PC bridges, "Reflected P wave automation using threshold The validity of the "analysis" is determined by a total of 38 sheaths to be measured that have been found to be "completely filled" shown in Tables 4 and 5, and the sheaths that have been found to be "unfilled (empty)" shown in Table 6. Verification is performed using 15 sheaths to be measured.

The received sheath waves used in the analysis are a total of 853 waves acquired as part of the applicant's research work during the research to establish the methodology for grout filling exploration of existing PC bridges from November 2005 to December 2010. It is arbitrarily selected from the reflected P wave and the reflected S wave of the sheath tube.

The grouting state of the sheath to be measured shown in Tables 4 and 5 is indicated by a black circle as "completely filled". This is confirmed by either visual inspection by cutting or drilling from a position directly above the sheath.

The grout filling state of the sheath to be measured shown in Table 6 is "unfilled (empty)" with white circles. This is confirmed by either visual inspection by cutting or drilling from a position directly above the sheath.

表４、表５、及び表６には、探査を妨害する反射波を生じさせる版厚ｄ_ｗ、及び２段目シースかぶり厚ｄ_２ｓと、コンクリート縦波音速Ｖ_ｐと、シース径φ_ｓと、ＲＣレーダ計測かぶり厚ｄｓ｜_ＲＣと、分析用１次かぶり厚ｄｓ_（１）、またはｄｓ_（１）｜_大及びｄｓ_（１）｜_小と、分析用２次かぶり厚ｄｓ_（２）、またはｄｓ_（２）｜_大及びｄｓ_（２）｜_小とを、分析用係数として記載している。

Tables 4, 5, and 6 show the slab thickness d _w that causes reflected waves that interfere with exploration, the second sheath cover thickness d _{2 s} , the concrete longitudinal wave speed V _p , and the sheath diameter φ _s . , the RC radar- _measured cover thickness ds| _RC and the primary cover thickness for analysis ds ₍₁₎ , or ds _{(1) | large} and ds ₍₁₎ | ds ₍₂₎ | _large and ds ₍₂₎ | _small are listed as analysis coefficients.

Although the RC radar measurement positions are specified to be two measurement points i=1 and i=4, in this analysis example, measurement is performed only at i=1 or 4.

First, the measurement analysis of the sheath to be measured, which has been found to be "completely filled" by visual inspection of the girder beam assumed sheath embedded concrete model, cut beam, or drilling in Tables 4 and 5, will be described in detail. Note that the center-to-center distance a between the transmitting probe and the receiving probe used in the measurement is a=200 mm for all the sheaths to be measured.

A total _of 38 sheaths to be measured on existing PC bridges that are known to be "completely filled" and are different in _principle . _tp(1) | _RC , and apply the concrete longitudinal wave velocity _Vp measured by a partition wall or the like with a known thickness near the measurement point of the sheath to be measured. Using the primary _reflected P-wave occurrence time for analysis _tp(1) | _RC , the secondary reflected P-wave occurrence time for analysis _tp(2) = _tp(1) | When _the threshold _analysis is performed in ₍ step S107) and in the first analysis processing of FIG _{. (1)} | _small is obtained, and analysis 1 Using the next reflected _P -wave occurrence time t _p(1) , or t _p(1) | _large , or t _{p( 1} ) | t _p(2) | _large or t p( _{2 )} | explain what

FIG. 40(a) shows the analysis primary reflected P-wave occurrence time _tp(1) | _RC as the analysis primary reflected P-wave occurrence time _tp(1) , and from problem (1) From _the time- _swept normalized spectral values SP _{f2(1) (} t) | The displayed spectral values SP _t* | _{i=1 to 4} are obtained and shown.

FIG. 40(b) shows the secondary reflected P-wave occurrence time t for analysis that addresses all of the problems (1) to (4) in the processing flow of FIGS. _p(2) or t _p(2) | _large or t _p(2) | _small time sweep standardized spectrum value SP _f2(2) ( _t ) | Normalized display spectral values SP _{t* | i=1 to 4} at cursor t*=t _p(2) +* are obtained and shown.

However, since the display of some sheaths to be measured overlaps with other sheaths to be measured, illustration is omitted and a total of 35 sheaths are shown. Hereinafter, description will be made using a total of 35 sheaths to be measured.

In order to clarify the comparison between FIGS. 40(a) and 40(b), the horizontal axis is the primary cover thickness for analysis ds ₍₁₎ (≈radar measurement cover thickness ds| _RC ), and the vertical axis is The axis is displayed for each i=1 to 4 as the normalized display spectrum value SP _t* . In addition, the standardized display spectrum values SP _t* | _{i = 1 to 4} are obtained from the virtual line segment of the concrete surface directly above the sheath to be measured at a measurement position of about 110 to 120 mm from left to right in principle for each sheath to be measured. It shows the values of the measuring points that move upwards.

In FIG ^. 40(a), the standardized display spectrum value SP _{t * |} , and the standardized display spectrum values SP _t* | _i below the empty-filling judgment line segment α ^∼ _σ = 0.56 are shown by black circles indicating “complete filling”.

By the way, all measured sheaths in Tables 4 and 5 that were analyzed were drilled or otherwise confirmed as "fully filled". If this were true, all the normalized display spectral values SP _t* | _i in FIG. The ratio of the sheaths set as “completely filled” to “completely filled” in the analysis with the analysis primary reflected P-wave occurrence time t _{p (1)} = t _p | _RC is (14 / 35 )×100=about 40%, which is an analysis result group with an extremely low percentage of correct answers.

On the other hand, as shown in FIG. 40(b), the analysis secondary reflection P-wave occurrence time t _p(2) or t _p(2) | SP _{f2(2) (} t _* )| _i (= normalized display spectral value SP _t* | _i ) obtained using _large or t _p(2 ) |small is drilled or otherwise “completely filled ”, the standardized display ^spectrum value _{SP t*} | It falls below _{σ 2} =0.56 and is marked with a black circle indicating "complete filling".

In addition, the measurement points of the sheaths to be measured "24" and "25" indicated by the circled numbers of the same bridge, and the sheaths to be measured "30" and "31" indicated by the circled numbers of the other same bridge Some are determined to be "unfilled (marked with double circles in the figure)" and some are determined to be "completely filled (marked by black circles in the figure)". It can be judged that this is the measurement analysis result at the boundary position between the gap and the filling portion of the sheath to be measured, which happens to have the above problem (3).

The measurement target sheaths indicated by the circled numbers "24" and "25" are analyzed as "unfilled" at the measurement point i = 1 and "completely filled" at the measurement points i = 2, 3, 4, The sheaths to be measured indicated by circled numbers "30" and "31" are analyzed as "completely filled" at measurement points i=1 to 3 and "unfilled" at measurement point i=4.

From this, the analysis result of the grout filling state (complete filling) at the filling state specific position of all 35 sheaths to be measured is analyzed as "complete filling". The analysis result of FIG. 40(b) using the secondary reflected P-wave occurrence time t _p(2) for analysis, or t _p(2) | _large , or t _{p(2) |} It is judged that the correct answer rate is 100% for all 35×4=140.

The "threshold reflection P-wave analysis method" using the secondary reflection P-wave occurrence time _tp(2) for analysis is extremely effective in investigating the filling state inside the sheath tube, and one of the causes of misjudgment. The first is the misidentification of the radar-measured cover thickness ds| _RC and the concrete longitudinal wave speed _Vp used in the analysis (problem (1) above). In addition, analysis that addresses other problems (2) to (4) also shows that the grout filling state of the sheath to be measured can be determined with extremely high accuracy.

Next, we describe what the threshold analysis results are for the received waves of the 15 measurement target sheaths in an existing PC bridge that has been found to be "unfilled" by drilling or other methods in Table 6.

Occurrence time t _p | _RC obtained by applying the radar _- measured cover thickness _ds | was found to be highly inadequate in Table 4 above, and in FIG. there is From this, the analysis secondary reflection P-wave occurrence time t _p(2) or t _p(2) | _large , or t _p(2) | The time-swept normalized spectral values SP _f2(2) (t)| _i (=SP _t* | _i ) by threshold analysis using _small are shown in FIG.

Since the positions of the sheaths to be measured are located at the ends of the girders and side walls as much as possible, the measurement positions are selected as shown in FIG. FIG. 41 (on the right side of the figure) shows the grout filling state assumed from the analysis result for each sheath to be measured.

Five measurement target sheaths analyzed as "unfilled" at all measurement points i = 1 to 4 ("3", "6", "9", "10" indicated by circled numbers on the right side of the figure) , and “12”), and there are other 10 sheaths to be measured that are determined to be the boundary positions between the gap and the filling portion.

FIG. 41 shows that any of the measurement points i=1 to 4 in the sheath to be measured that has been set as “unfilled” by drilling or other methods is “unfilled”, “underfilled”, or “void and filled portion”, or “fully filled”, “unfilled” is indicated by a double circle, and “underfilled” is indicated by a white triangle for each standardized display spectrum value SP _t* | _i. , and "completely filled" is indicated by a black circle.

Problems (1) and (2) are dealt with in the analysis of all sheaths to be measured, and secondary reflected P-wave occurrence time t _p(2) for analysis or t _p(2) | _Large or t _p(2) | _Small is used for threshold analysis to deal with problems (3) and (4). It is judged that the correct answer rate is 100% in all cases.
In addition, in FIG. 41, the drilling empty sheath indicated by the circled number "11" is "unfilled (empty)" at the measurement points 1 and 2 of Analysis Example 2 in Table 3, and "not filled (empty)" at the measurement points 3 and 4. 32(a), 32(b), 33(a), 33(b), 34(a) and 34(b).

<Optimal probe spacing for reflected P-wave measurement>
The above-described reflected P-wave measurement is performed with a probe outer diameter of φ100 mm (oscillator diameter and receiver diameter of φ78 mm) and a center-to-center distance a between the transmitting probe 11a and the receiving probe 12a of 200 mm. be. There are three types of reflected waves from the sheath to be measured: the sheath reflected P wave, the sheath reflected _M1 wave, and the sheath reflected _M2 wave.

As shown in FIG. 42, the amplitudes of these waves are determined by the linear distance d between the probe, which is the reflection source, and the sheath to be measured, and the center-to-center distance a between the transmitting probe 11a and the receiving probe 12a. changes greatly in relation to As the sheath cover thickness ds of the sheath to be measured becomes shallower, the center-to-center distance a/linear distance d changes from "small" to "large" as shown in FIG. 28(b), FIG. 32(a), FIG. 35(a), and FIG. 38(a), etc., it becomes difficult to specify the occurrence time _tp(1) of the sheath reflected P wave.

This problem can be dealt with by changing the center-to-center distance a=200 mm to around 110 mm to 120 mm. As an example, an example of acquisition of the primary cover thickness ds ₍₁₎ for analysis at a center-to-center distance a=110 mm using a sheath to be measured with a sheath cover thickness ds=115 mm is obtained using the F3(f) filter by the first analysis process. It is obtained using the function and the time filter function TGC4(t) and is shown in FIGS. 43(a) and 43(b).

In FIG. 43(a), the frequency band for analysis is around the center frequency f _s =80 kHz. Center-to-center distance a/straight-line distance d=110/115≈0.95. The fog thickness ds ₍₁₎ and the analysis primary reflected P-wave occurrence time t _p(1) values can be clearly specified.
Based on this, it is determined that the center-to-center distance a should be about 110 mm to 120 mm in the threshold analysis method using reflected P waves.

When the center-to-center distance a is about 200 mm, the reflected P-wave analysis becomes difficult when the sheath cover thickness ds is 150 mm or less. This is due to the problem (2) described above, and the occurrence time intervals of the sheath reflection P wave, the sheath reflection _M1 wave, and the sheath reflection _M2 wave are different from those shown in FIGS. ) is extremely narrow.

<Labor saving of reflected P-wave measurement analysis in threshold analysis>
Analytical secondary reflected P-wave occurrence time _tp(2) and analytical secondary cover thickness ds ₍₂₎ described above, or analytical _secondary reflected P-wave occurrence time _tp(2) | Secondary fog thickness ds ₍₂₎ | _{large ,} or _secondary reflected P-wave occurrence time t _{p (2) |} According to FIG. 40(b) and FIG. 41, which are the threshold analysis results of (i = 1 to 4), the grout filling state at all measurement points is accurately "completely filled", "unfilled", or "underfilled". ” has been determined.

Therefore, even if the ultrasonic measurement is replaced with the single-point measurement shown in the lower part of FIG. 44 instead of the multi-point measurement shown in the upper part of FIG. Using the time-swept normalized spectrum value SP _f2(2) (t)| _i=1 in single-point measurement, No. 1 or No. The analysis determination of the grout filling state at the measuring point 1' may be performed in the first process (step S107).

In addition, No. 1 is on the girder end side and is judged to be "completely filled", the No. 1 on the girder center side is 1' is physically "fully filled" and does not require metrological analysis determination. Conversely, No. 1' is on the girder end side and is judged to be "completely filled", the No. 1 on the girder center side. Measurement analysis judgment in 1 is unnecessary.

Single-point measurement can be positioned as a main method used in threshold analysis because the measurement work efficiency and analysis work efficiency are extremely high compared to multi-point measurement. On the other hand, the threshold analysis by multi-point measurement makes it possible to check how the problems (1) to (4) are being dealt with in the analysis judgment of the grout filling state by the transition of the analysis screen, so the analysis technique of the analysis operator It can also be positioned as a means to improve ability.

_{^{<A G (f) Threshold reflection P-wave automated analysis using nG filter function>}}
A method of analyzing and determining the grout filling state of the sheath to be measured using the _AG (f) ^nG filter function along the flow of the threshold reflection P-wave automated analysis of FIGS.
In the above-mentioned "threshold reflected P-wave automated analysis" and "threshold reflected P-wave automated analysis example", the received wave (i = 1 to nw) shown in FIG. _The received _wave spectrum F(f ₎ | spectrum.

On the other hand, in this threshold reflected P-wave automated analysis, the A _G (f) ^nG filter function is used instead of the A _K (f) filter function in the second analysis process (step S105), and the analysis spectrum FA(f) | _{i = 1 to nw+1 and} time series for analysis GA(t)|

FIG. 45 shows the difference between the A _K (f) filter function and the A _G (f) ^nG filter function.
The A _K ( _f ) filter function shown _in the left diagram of _FIG . , and extracts more of the 80 kHz band spectrum from the center frequency f ₀ =20 kHz spectrum and the frequency f ₂ =60 to 80 kHz spectrum. Spectra FA(f)| _{i=1 to nw+1} extracted in the second analysis process using this A _K (f) filter function are used as analysis spectra, and corresponding time series GA(t)| _{i= 1 to nw+1} are used as time series for analysis.

On the other hand, the A _G (f) ^nG filter function is a filter function whose central frequency is a separately determined frequency f _k as shown in the right diagram of FIG. 45 . Using this A _G (f) ^nG filter function, the spectrum FA(f)| _{i=1 to nw+1} extracted in the second analysis process is used as the spectrum for analysis, and the corresponding time series GA(t)| _{i =1 to nw+1} are used as time series for analysis.

Such an A _G (f) ^nG filter function has _a sinusoidal increasing function, a sin-shaped decreasing function that becomes "1.0" at the frequency f _k and "0.0" at the frequency f _k ×2, and a function that becomes "0.0" at the frequency f _k ×2 or higher is.

The frequency f _k is automatically set to f _k =(f _w +f ₂ ^∼ )/2 (where f ₂ ^∼ =80 kHz). However, it is possible for the operator to set any value within the range of (f _w + f ₂ ^∼ )/2 to f ₂ ^∼ .
In addition, the index nG is the value when any of the measurement points ⁱ of the ^spectrum for analysis FA(f)| _i has _the maximum spectral value between the frequencies f _{w ~} f in the above _f2 ). The frequency f _w is set by the operator to any value within the range of 40 kHz−Δf _w <f _w <40 kHz+Δf _w (where Δf _w =5 kHz).

Hereinafter, a method for analyzing and determining the grout filling state using the _AG (f) ^nG filter function will be described along the flow of the threshold reflection P-wave automated analysis shown in FIGS.
First, in the first recording process (step S102) and the second recording process (step S103), the processing contents described above are used as they are, and the received wave G(t) _| to be recorded.

In the first analysis process (step S104), the above-described process contents are used as they are, and the sheath cover thickness pattern is "pattern (0)", "pattern (1) to (4)", or "pattern (1' ) to (4′)”.

In the case of "pattern (0)", the analysis primary reflected P-wave occurrence time t _{p (1)} and the analysis primary cover thickness ds ₍₁₎ are obtained, and "pattern (1) to (4)" or In the case of “patterns (1′) to (4′)”, the primary reflected P-wave occurrence time t _p(1) for analysis _{is large} , and the primary cover thickness ds ₍₁₎ for analysis is _large and 1 for analysis. Next reflected P-wave occurrence time t _p(1) | _small and primary cover thickness for analysis ds ₍₁₎ | _small are obtained. In addition, the start station nA and end station nB for each pattern of sheath cover thickness are set as shown in Table 1 above, as in the case of using the Ak(f) filter function.

Next, in the second analysis process (step S105), the multi-point measurement reception wave G(t)| _{i=1 to nw and} these averaging waves G(t)| For the received wave spectrum F(f)| _{i=1 to nw+1} obtained by FFT transforming the wave group G(t)| _{i=1 to nw+1} , instead of the A _K (f) filter function, A _G (f) Multiply ^{the nG} filter function to obtain the analysis spectrum FA(f)| _{i=1 to nw+1} shown in FIG. Create _{i=1 to nw+1} (the thick solid line in the figure indicates i=nw+1).

According to the analysis time series GA(t) | _{i=1 to nw+1} in FIG. In both of the mean waves (thick solid lines), the mixture of the surface _P1 wave, the surface _S1 wave that propagates through the concrete upper surface 4a, and the rear residual wave of the direct wave (DI wave) that propagates shallowly in the surface layer is reduced, and the sheath It can be seen that the generation of reflected P waves is dominant.

This phenomenon is caused by the fact that, in this measurement example, the cover thickness ds of the sheath to be measured does not change in the longitudinal direction of the sheath, and ds is as deep as 212 mm. If the sheath cover thickness ds is shallow, these backward residual waves are mixed on the sheath reflected P wave, causing an erroneous determination of the grout filling state.

For this reason, in the case of the reflected P-wave automated analysis using the A _K (f) filter function, the analyzable sheath cover thickness ds is ds≧150 mm, but the reflected P-wave automated analysis using the A _G (f) ^nG filter function Then, the surface P ₁ wave, the surface S ₁ wave, and the direct wave (DI wave) of frequency f ₂ ^~ f _w ~ f ₂ ^~ less damped frequency may mix on the sheath reflected P wave. There is Therefore, in the automated analysis using the A _G (f) ^nG filter function, by changing the sheath cover thickness ds that can be analyzed and determined from ds ≧ 150 mm to ds ≧ 200 mm, the above-mentioned surface P ₁ wave, surface S ₁ wave, It eliminates the situation where the direct wave (DI wave) mixes on top of the sheath reflected P wave.

Similar to the use of the A _K (f) filter function in the left panel of FIG. 45, the use of the A _G (f) ^nG filter function in the right panel also allows subsequent analysis to show that the pattern of sheath cover thickness in FIG. (0)" (step S106: No), the process proceeds to the first process, and if "pattern (1) to (4)" or "pattern (1') to (4')" (step S106: Yes), the process sequentially shifts to the second process and the third process.

First, the third to eighth analysis processes (steps S111 to S119) in the first process (step S107) will be described.
In the third analysis process (step S111), the above process contents are used as they are, and the analysis _primary reflection P-wave occurrence time t Time filters TGC1(t) and TGC2(t) created using _p(1 ) and Δt _h1 = 6 μs are multiplied by the above-described analysis time series GA(t) | _{i = 1 to nw + 1} for analysis. , and the corresponding spectrum FB _{(1) (} f)| _{i =1 to nw+1} .

In the fourth analysis process (step S111 ₎ , the above-described process contents are used as _they are _. .0, and threshold processing is performed to set the maximum value of the spectrum with the above frequency _{f w} or higher to _0.5. A primary time series GC ₍₁₎ (t) | _{i=1 to nw+1} is obtained.

In the fifth analysis process (step S111), the contents of the above process are used as they are, and the trapezoidal window function A is obtained by the time sweep process from time t _p(2) −Δt _p1 to time t _p(2) +Δt _p2 . Time-swept normalized spectrum value SP _f2(1) (t)| _{i=1 to nw+1 and} time-swept f ₀ , f ₂ spectrum SP _f2(1) (f, t) the time-swept normalized spectral values SP _f1,2(1) (t)|i ⁼ _{1 to nw+1} when using the A _G (f) ^nG filter function instead of _{nc |i=1 to nw+1} , and Time sweep f ₀ , (f ₁ to f ₂ ) spectrum SP _{f 1,} ² _{( 1} ) ( _f , _t ) ^nc | Frequency f ₁ =40-50 kHz, frequency f ₂ =60-80 kHz, nc=2).

Next, in the sixth analysis process (step S112), the above-described process content is used as it is, and the time-swept standardized spectrum value SP _f1 obtained using the start station nA and the end station nB defined in Table 1 _{, 2(1)} (t) | _{i=nA to nB} shape characteristics are specified as characteristics TA, and after specifying the boundary survey point n1 (step S113: 1), the first TA process of the seventh analysis process, and sequentially shift to the second TA process.
Alternatively, after the shape characteristics of the time-swept normalized spectral values SP _f1,2(1) ( _t )| The process sequentially shifts to the first TB process and the second TB process of the eighth analysis process.

Subsequently, the first TA processing and the second TA processing in the seventh analysis processing will be explained. This is the process for both multipoint and single point measurements.

(First TA treatment)
In the first TA process (step S114) in the seventh analysis process, the above-described process contents are used as they are to specify the analysis secondary reflected P-wave occurrence time _tp(2) , and the third analysis process is performed again. In the process of , the analysis cutout wave GB (2) (t) is obtained by replacing the analysis primary reflected P-wave occurrence time _tp(1) with the analysis secondary reflection P-wave occurrence time _{tp (2)} | _{i=1 to nw+1} and corresponding spectra FB ₍₂₎ (f) | _{i=1 to nw+1} are generated.

Next, the first TA process uses the frequency f _w in the _AG (f) ^nG filter function in re-thresholding by the fourth analysis process to obtain the secondary spectrum for analysis FC ₍₂₎ (f) | _{i=1 to nw+1} are created, and corresponding secondary time series GC ₍₂₎ (t)| _{i=1 to nw+1} for analysis are obtained.

Furthermore, in the first TA process, the time sweep standardized spectrum value SP _{f1,2(2) (} t ) | _{i=1 to nw+1} and time sweep f ₀ , (f ₁ to f ₂ ) spectrum SP _f1,2(2) (f, t) ^nc | _{i=1 to nw+1} (where MEM spectrum display, nc= 2) is created, it can be displayed on the display unit 135 by receiving an operator's operation.

By the way, the addition average wave created in the first TA process is created using the secondary time series GC for analysis of the measurement points i = nA ~ n1 instead of the measurement i = nA ~ nB ₍₂₎ (t) | _i There is a need.
Therefore, the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 is replaced with the WAVE addition average wave GC ₍₂₎ ( _t )| and SP addition average wave GC ^~ _{(2) (} t) | _{of the} time-swept normalized _spectrum values SP f1,2 _{( 2 )} (t)| t) ^nc | _i=nw+1 (however, the MEM spectrum display, nc=2) is recreated, and then the operator's operation is received and the display unit 135 can display them respectively.

Next, the time-swept normalized spectral values SP _f1,2(2) (t)| _{i=nA to n1} and the time-swept normalized spectral values SP _f1,2(2) (t)| _{i = nw + 1} , the grout filling state at each of the measurement points i = nA to n1 and at the SP addition i = nw + 1 is added to the grout filling state determination formula of formula 16 with the empty determination cursor t _* = t _{p ( 2)} After applying the time-swept normalized spectral value SP _{f1,2 (2)} (t _* )| _i (=SP _t* | _{i = nA to n1, nw+1} ) obtained using +*, The determination result in the first TA process and the time-swept standardized spectrum value SP _f1,2(2) (t)| _{i=1 to nw+1} (SP addition) are automatically displayed together on the display unit 135. .

Two time-swept normalized spectrum values SP _f1,2(2) (t)| _{i=1 to nw+1} and two time-sweep f ₀ , (f ₁ to f _{2 )} spectrum SP _{f1, 2 (2)} (f, t) ^nc | The presence or absence of 4) can be confirmed.

Then, using the starting measuring point nA and the ending measuring point nB of the sheath cover thickness pattern in Table 1 obtained in the first analysis process, if n1=nB (step S115: Yes), measuring point i=nA Since the grout filling state at all measurement points of ~nB has already been determined, the second TA processing of the seventh analysis processing is skipped, and all processing ends. Note that all processing is terminated even in the case of single-point measurement.
On the other hand, if n1<nB (step S115: No), the process proceeds to the second TA process in order to determine the grout filling state at the measurement point i=n1+1 to nB.

(Second TA processing)
The second TA process (step S116) in the seventh analysis process specifies the analytical secondary reflected P-wave occurrence time _tp(2) using the above-described process contents as they are, and repeats the third analysis process again. In the processing, the analysis cutout wave GB _{(2) ( t} )| _{i =1 to nw+1} and the corresponding spectra FB ₍₂₎ (f)| _{i=1 to nw+1} .

Next, the second TA processing is a re-threshold processing by the fourth analysis processing, and uses the frequency f _w in the _AG (f) ^nG filter function to analyze the secondary spectrum FC ₍₂₎ (f) | _{i=1 to nw+1} are created, and corresponding secondary time series GC ₍₂₎ (t)| _{i=1 to nw+1} for analysis are obtained.

Furthermore, the second TA process is a second process of the fifth analysis process, and uses the analysis secondary reflected P-wave occurrence time t _p(2) to obtain the time-swept standardized spectrum value SP _f1,2(2) ( t) | _{i=1 to nw+1} and time sweep f ₀ , (f ₁ to f ₂ ) spectrum SP _f1,2(2) (f, t) ^nc | _{i=1 to nw+1} (where MEM spectrum display, nc = 2), it can be displayed on the display unit 135 by receiving an operator's operation.

By the way, the addition average wave created in the second TA process is created using the secondary time series GC for analysis of the measurement points i = n1 + 1 ~ nB, not the measurement i = nA ~ nB ₍₂₎ (t) | _i There is a need.
Therefore, the WAVE averaged wave GC ₍₂₎ (t)| _i=nw+1 is replaced with the WAVE averaged wave GC ₍₂₎ ( _t )| and SP addition average wave GC ^~ _{(2) (} t) | Time _- swept normalized _spectrum values SP f1,2 _{( 2 ) (} t)| ) ^nc | _i=nw+1 (however, the MEM spectrum display, nc=2) is recreated, and then the operator's operation is received and the display unit 135 can display them.

Next, the time-swept normalized spectrum value SP _f1,2(2) (t)| _{i=n1+1 to nB} and the time-swept normalized spectrum value SP _f1,2(2) ( _t )| Using the grout filling state at each of the measurement points i = n1 + 1 to nB and at the SP addition i = nw + 1, the empty filling determination cursor t _* = t _{p (2)} + After automatic determination by applying the time-swept normalized spectrum value SP _{f1,2 (2)} (t _* )| _i (=SP _t* | _{i=n1+1 to nB, nw+1} ) obtained using *, the second TA process and the time-swept standardized spectral _values SP _f1,2(2) (t)| exit.

Two time-swept normalized spectrum values SP _f1,2(2) (t)| _{i=1 to nw+1} and two time-sweep f ₀ , (f ₁ to f _{2 )} spectrum SP _{f1, 2 (2)} (f, t) ^nc | The presence or absence of 4) can be confirmed.

Next, the 1st TB processing and the 2nd TB processing in the eighth analysis processing will be described.
(First TB processing)
In the first TB process (step S117) in the eighth analysis process, the above-described process content is used as it is to specify the analysis secondary reflected P-wave occurrence time _tp(2) , and the third analysis process is performed again. In the processing, the analysis cutout wave GB _{( 2 )} (t)| _{i =1 to nw+1} and the corresponding spectra FB ₍₂₎ (f)| _{i=1 to nw+1} .

Next, the first TB processing is threshold processing again by the fourth analysis processing, using the frequency f _w in the _AG (f) ^nG filter function, the secondary spectrum for analysis FC ₍₂₎ (f) | _{i=1 to nw+1} are created, and corresponding secondary time series GC ₍₂₎ (t)| _{i=1 to nw+1} for analysis are obtained.

Furthermore, in the first TB processing, the time sweep standardized spectrum value SP _{f1,2 (2) (} t ) | _{i=1 to nw+1} and time sweep f ₀ , (f ₁ to f ₂ ) spectrum SP _f1,2(2) (f, t) ^nc | _{i=1 to nw+1} (where MEM spectrum display, nc= 2) is created, it can be displayed on the display unit 135 by receiving an operator's operation.

By the way, the additive mean wave created in the 1st TB process is created using the secondary time series GC for analysis of the measurement points i = nA ~ n1 instead of the measurement i = nA ~ nB ₍₂₎ (t)| _i There is a need.
Therefore, the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 is replaced with the WAVE addition average wave GC ₍₂₎ ( _t )| and SP addition average wave GC ^~ _{(2) (} t) | Time _- swept normalized _spectrum values SP f1,2 _{( 2 ) (} t)| ) ^nc | _i=nw+1 (however, the MEM spectrum display, nc=2) is recreated, and then the display unit 135 can receive the operation of the operator and display them on the display unit 135 respectively.

Next, time-swept normalized spectrum values SP _f1,2(2) (t)| _{i=nA to n1} and time-swept normalized spectrum values SP _f1,2(2) (t)| _i=nw+1 Using and, the grout filling state at each of the measurement points i = nA to n1 and at the SP addition i = nw + 1 is added to the grout filling state determination formula of formula 16 with the empty determination cursor t _* = t _{p (2)} After applying the time-swept normalized spectrum value SP _f1,2(2) (t _* )| _i (=SP _t* | _{i=nA to n1,nw+1} ) obtained using +*, the first TB The judgment result in the process and the time sweep normalized spectral values SP _f1,2(2) (t)| _{i=1 to nw+1} (SP addition) are automatically displayed together on the display unit 135 .

Two time-swept normalized spectrum values SP _f1,2(2) (t)| _{i=1 to nw+1} and two time-sweep f ₀ , (f ₁ to f _{2 )} spectrum SP _{f1, 2 (2)} (f, t) ^nc | The presence or absence of 4) can be confirmed.

Then, using the starting measuring point nA and the ending measuring point nB of the sheath cover thickness pattern in Table 1 obtained in the first analysis process, if n1=nB (step S118: Yes), all of nA to nB Since the grout filling state at the measurement point has already been determined, the second TB processing of the eighth analysis processing is skipped, and all processing ends. Note that all processing is terminated even in the case of single-point measurement.
On the other hand, if n1<nB (step S118: No), the process proceeds to the second TB process in order to determine the grout filling state at the measurement point i=n1+1 to nB.

(2nd TB processing)
In the second TB process (step S119) in the eighth analysis process, the above-described process contents are used as they are to specify the analysis secondary reflected P-wave occurrence time _tp(2) , and the third analysis process is performed again. In the processing, the analysis cutout wave GB _{(2 ) (} t)| _{i= 1 to nw+1} and spectra FB ₍₂₎ (f) | _{i=1 to nw+1} are created.

Next, the second TB processing is threshold processing again by the fourth analysis processing, using the frequency f _w in the _AG (f) ^nG filter function, the secondary spectrum for analysis FC ₍₂₎ (f) | _{i=1 to nw+1} are created, and corresponding secondary time series GC ₍₂₎ (t)| _{i=1 to nw+1} for analysis are obtained.

Furthermore, the second TB process is a second process of the fifth analysis process, and uses the analysis secondary reflected P-wave occurrence time t _p(2) to obtain the time sweep standardized spectrum value SP _f1,2(2) ( t) | _{i=1 to nw+1} and time sweep f ₀ , (f ₁ to f ₂ ) spectrum SP _f1,2(2) (f, t) ^nc | _i=nw+1 (where MEM spectrum display, nc=2 ) is created, it can be displayed on the display unit 135 in response to an operator's operation.

By the way, the average wave created in the 2nd TB process is created using the secondary time series GC ₍₂₎ (t) _| There is a need to.
Therefore, the WAVE averaged wave GC ₍₂₎ (t)| _i=nw+1 is replaced with the WAVE averaged wave GC ₍₂₎ ( _t )| and SP addition average wave GC ^~ _{(2) (} t) | _{of the} time-swept normalized _spectrum values SP f1,2 _{( 2 )} (t)| t) ^nc | _i=nw+1 (however, MEM spectrum display, nc=2) is recreated, and then it can be displayed on the display unit 135 in response to an operator's operation.

Next, the time-swept normalized spectral values SP _f1,2(2) (t)| _{i=n1+1 to nB} and the time-swept normalized spectral values SP _f1,2(2) (t)| _i=nw+1 Using and, the grout filling state at each of the measurement points i = n1 + 1 to nB and at the SP addition i = nw + 1 is added to the grout filling state determination formula of formula 16 with the empty filling determination cursor t _* = t _{p (2)} After automatic determination by applying the time-swept normalized spectrum value SP _f1,2(2) (t _* )| _i (=SP _t* | _{i=n1+1 to nB,nw+1} ) obtained using +*, the second TB The judgment result in the process and the time sweep standardized spectrum value SP _{f1,2(2) (} t)| End the process.

Two time-swept normalized spectrum values SP _f1,2(2) (t)| _{i=1 to nw+1} and two time-sweep f ₀ , (f ₁ to f _{2 )} spectrum SP _{f1, 2 (2)} (f, t) ^nc | The presence or absence of 4) can be confirmed.

Next, the second processing and the third processing will be described.
If the sheath cover thickness patterns are "patterns (1) to (4)" and "patterns (1') to (4')" shown in FIG. using the starting and ending measuring points _nA and nB of the _primary cover thickness for analysis ds ( _{1 )} | The third process (step S109) is performed in this order.
However, in the case of single-point measurement, analysis is performed in the first process, so the second process and the third process are not performed.

The analysis flow and processing details in the second process (step S108) are the same as those in the above-described first process (step S107). However, the third to eighth analysis processes in the second process are the primary reflection P for analysis of the third to eighth analysis processes (steps S111 to S119) in the first process. Replacing the wave occurrence time t _p(1) with t _p(1) | _large , replacing the _primary cover thickness ds ₍₁₎ for analysis with ds ₍₁₎ | _{p (2 ) to tp ( 2 ) | 1)} | _Large , replace the analytical secondary sheath reflection _M1 wave occurrence time _tM1(2) with _tM1(2) | _Large .

The analysis flow and processing details in the third process (step S109) are the same as those in the above-described first process (step S107). However, the third to eighth analysis processes in the third process are the primary reflection P for analysis in the third to eighth analysis processes (steps S111 to S119) in the first process. Replacing the wave generation time t p _{( 1)} with t _p(1) | _small , the analysis primary cover thickness ds ₍₁₎ with ds ₍₁₎ | _p(2) is set to _tp(2) | _small , the analytical secondary cover thickness ds ₍₂₎ is set to ds ₍₂₎ | _small , and the sheath reflection _M1 wave occurrence time _tM1(1) is set to _{tM1( 1)} | _small replaces the analytical secondary sheath reflection _M1 wave occurrence time t _M1(2) with t _M1(2) | _small .

A method for confirming the presence of problem (4) in the threshold analysis using the A _G (f) ^nG filter function and a method for coping with it will be organized. First TA processing (step S114) and second TA processing (step S116) of the seventh analysis processing for each of the first processing (step S107), second processing (step S108), and third processing (step S109) , and in the first TB processing (step S117) and the second TB processing (step S119) of the eighth analysis processing, the analysis _secondary reflected P-wave occurrence time _tp(2) or _tp(2) | For each _small t _{p (2)} |, select a group of measurement points corresponding to the sheath to be measured, and perform the WAVE addition of Equation 14 above, the SP addition of Equation 15 above, or the WAVE addition of Equation 22 above, Via the _SP addition of Equation ₂₃ , _the time-swept normalized spectral values SP _{f1,2 (2) (} t)| ₂₎ (f, t) ^nc | _{i = nw + 1} (where MEM spectrum display, nc = 2) can be obtained by both WAVE addition and SP addition, and can be displayed on the display unit 135 in response to an operator's operation. and

Since the addition wave that obtains the correct answer is SP addition, in the automated processing of i = nw + 1, the time sweep normalized spectrum value SP _{f1,2 (2) (} t)| It shows the analysis result of the state.
By the operator's operation, the time-swept normalized spectrum value SP _{f1,2(2) (} t)| , the presence or absence of the problem (4), and the validity of the analysis result of the grout filling state of the sheath to be measured by the SP addition can be confirmed by the operator.
Such a comparison of analysis results is positioned as a means for improving the operator's analysis and examination ability in this threshold analysis.

In the following, multi-point measurement with nw = 4, the flow of threshold analysis using the A _G (f) ^nG filter function of the sheath to be measured in which all of the measurement points i = 1 to nw are in the “unfilled” state , FIG. 47(a), FIG. 47(b), and FIG.
The analysis examples of the four sheaths to be measured in Table 3 show the flow of processing in _the case of using the A _K (f) ^filter function in a multifaceted manner. Analysis follows the same process flow.

This A _G (f) flow of threshold analysis using ^{the nG} filter function is as follows: in the first analysis process, the sheath embedding state is "pattern (0)", the starting point nA = 1, the sheath cover thickness does not change, Arithmetic averaging with sheath specified as end station nB = 4 and analytical primary reflected P-wave onset time _tp(1) = 125 µs (analytical primary cover thickness ds ₍₁₎ = 255 mm) Only the wave G(t)| _i=nw+1 (with center-to-center distance a=200 mm and nw=4) is used in detail.

First, FIG. 47(a) will be described.
The thin line _indicated by the circled number “1” in the _figure is _the ^A _G (f) Analytical spectrum FA (f) obtained by multiplying received wave spectrum F (f) | _{i = 1 to nw + 1} in measurement directly above the sheath to be measured with ^nG filter function as center distance a = 200 mm | The analytical time series GA(t)|i _=nw+1 corresponding to _i=nw+1 .

In addition, the thick line indicated by the circled number “2” in the figure corresponds to the cutout wave for analysis GB ₍₁₎ (t)| _{i=1 to nw+1} obtained in the third analysis process in the first process. _Spectrum FB _{( 1) ( f )} ^| _{FC (1)} ( _f )| Analytical first-order time series GC _{(1) (} t)| GC ₍₁₎ (t)| _{i= nw+} 1 for i=1 to nw+1.

Note that in the third analysis process, the above-described time filter function TGC1(t) and time filter function TGC2(t) are used to acquire the analysis clipping wave GB ₍₁₎ (t)| _{i=1 to nw+1.} However, in this analysis example, the amplitude of the sheath reflected wave is large because it is immediately after concrete is placed, and the sheath cover thickness ds ₍₁₎ is 255 mm (the primary reflected P wave generation for analysis Time t _{p (1)} = 125 μsec), the amplitude of the backward residual wave of the concrete surface S ₁ wave and the direct wave (DI wave) becomes smaller than the amplitude of the sheath reflected P wave, and the time filter function TGC1 (t), and the use of the time filter function TGC4(t) shown instead of the time filter function TGC2(t) does not adversely affect the grout filling analysis results.

As a result, in this analysis example, the time filter function TGC4(t) is used which sets the time t _h =t _p(1) =125 μs indicated by the circled number “4” in the figure. The circled number "3" in the figure indicates the time when the plate thickness reflection P wave occurs.

FIG. 47(b) shows, in the fifth analysis process, the trapezoidal window function A _is applied to the primary time series GC for analysis ₍₁₎ (t)| _{i=1 to nw+1} at time t (=t _{p(1 )} −Δt _p1 ) to _{the end of} time t (=t _p(1) +Δt _p2 ) is shown for i=nw+1 only. In this context _, the time _- swept normalized spectrum values SP _{f1,2 (1) ( t} )| (f, t) ^nc | _i=nw+1 (where MEM spectral representation, nc=2) is obtained.

Next, in the sixth analysis process, the shape characteristics of the time-swept standardized spectral values SP _f1,2(1) (t)| _{i=1 to nw} are as shown in FIGS. Since the characteristic TA and n1 = nB = 4 are specified (step S113: 1), the process proceeds to the seventh analysis process, and the analysis secondary reflected P-wave occurrence time t _{p ( 2)} , the time-swept standardized spectrum value SP _f1,2(2) (t) | _{i=1 ∼ nw+1} and time sweep f ₀ , (f ₁ to f ₂ ) spectrum SP _{f1,2(2) (} f,t) ^nc | and two time-swept normalized spectral values SP _f1,2(2) (t)| _{i=1 to nw+1} of WAVE addition and SP addition, respectively, and two time sweeps f ₀ , (f ₁ to f ₂ ) A spectrum SP _f1,2(2) (f, t) ^nc | _i=nw+1 is obtained.

Although detailed illustration is omitted, in this analysis example, by chance, the secondary reflected P-wave occurrence time for analysis _tp(2) ≈ the primary reflected P-wave occurrence time for analysis _tp(1). , time sweep normalized spectrum value SP _f1,2(2) (t)| _{i=1 to nw} ≈ time sweep normalized spectrum value SP _f1,2(1) (t)| _{i=1 to nw} , time sweep f ₀ , (f ₁ to f ₂ ) spectrum SP _f1,2(2) (f, t) ^nc | _{i=1 to nw} ≈ time sweep f ₀ , (f ₁ to f ₂ ) spectrum SP _{f1,2(1 ) (} f _, t ₎ ^nc | and _the time _- swept standardized spectrum value SP _{f1, 2 (2) (} t) | Applied to the filling state judgment formula, it is judged as "unfilled" at all measurement points, and the process ends.

FIG. 48 shows a time sweep f ₀ , (f ₁ to f ₂ ) spectrum SP _{f 1, 2 (2)} (f, t) ^nc | _i=nw+1 (where MEM spectrum display, nc=2) by SP addition. It is a thing. A spectrum of frequencies f _w to f ₂ occurs greatly, and the time sweep f ₀ , (f ₁ to f ₂ ⁾ spectrum indicates that the sheath to be measured is “unfilled”, and the drilling result is "unfilled".
Note that the time sweep f ₀ , (f ₁ to f ₂ ) spectrum SP _{f1, 2(2)} (f, t) ^nc normalizes the maximum spectrum value to "1.0" in all analysis times t. , nc=2.

By the way, in FIG. 48, the occurrence of the spectrum of frequencies f _w to f ₂ ^, which indicates the “unfilled” sheath-reflected P-wave, continues for a relatively long period of time. On the other hand, in the transition of time using the spectrum of frequency f ₂ =80 kHz indicating “unfilled” in _FIG . Its duration is short.

FIG. 48 is a sweep spectrum in which the frequencies on the low frequency side with less attenuation are dominant among the frequencies f _w to f ₂ ^, and FIG. This is a phenomenon caused by the fact that the spectrum at ₂ =80 kHz is the dominant sweep spectrum.
The nondestructive inspection device 10 based on the reflected P-wave threshold analysis method that realizes the above operation and the nondestructive inspection method using the same can efficiently and accurately nondestructively inspect the grout filling state. can.

Further, the software functions of the series of first analysis processing, second analysis processing, third analysis processing, fourth analysis processing, and fifth analysis processing described above are individually prepared, and these analysis functions After the operator applies the analysis result to the sixth analysis process, the third analysis process, the fourth analysis process, and the fifth analysis process in the seventh analysis process and the eighth analysis process are performed again, Further, even in the method of determining the grout filling state by semi-automated processing by an operator who repeatedly applies the fifth analysis processing, non-destructive inspection can be performed with high accuracy.

In correspondence with the configuration of this invention and the above-described embodiments,
The input reception means and operation reception means of the present invention correspond to the operation unit 134 of the embodiment,
and so on,
The concrete surface corresponds to the concrete upper surface 4a,
The sheath to be measured corresponds to the sheath tube 2,
First Recording Means, Second Recording Means, First Analysis Means, Second Analysis Means, Third Analysis Means, Fourth Analysis Means, Fifth Analysis Means, Sixth Analysis Means, Seventh Analysis Means The analysis means, the eighth analysis means, the first processing means, the second processing means, and the third processing means correspond to the control unit 136,
The input receiving step corresponds to step S101,
The first recording step corresponds to step S102,
A second recording step corresponds to step S103,
The operation reception step and the first analysis step correspond to step S104,
A second analysis step corresponds to step S105,
A first processing step corresponds to step S107,
A second processing step corresponds to step S108,
A third processing step corresponds to step S109,
A third analysis step, a fourth analysis step, and a fifth analysis step correspond to step S111,
A sixth analysis step corresponds to step S112,
The seventh analysis step corresponds to steps S114 to S116,
The eighth analysis step corresponds to steps S117 to S119,
The present invention is not limited to the configurations of the above-described embodiments, and many embodiments can be obtained.

2 Sheath tube 4a Concrete upper surface 10 Non-destructive inspection device 11a Transmitting probe 12a Receiving probe 13 Analyzing device 134 Operation unit 135 Display unit 136 Control unit

Claims (4)

It has a pair of probes consisting of a transmitting probe that transmits ultrasonic waves and a receiving probe that receives ultrasonic waves, and a display unit that displays at least various information, and analyzes the grout filling state of the sheath to be measured. A non-destructive inspection device comprising an analysis device for determining,
an input receiving means for receiving input of concrete longitudinal wave sound velocity, cover thickness of the second sheath, plate thickness, and path length of the bottom corner of the plate thickness, which are operated by the operator;
On the virtual line segment of the concrete surface along the longitudinal direction of the sheath to be measured that passes through the intersection of the concrete surface and the perpendicular line from the cross-sectional center of the sheath to be measured to the concrete surface, measuring points i = 1 to nw (however, , nw>1) are measured in order, and the average value of the sheath cover thickness at the measurement point i = 1 and the sheath cover thickness at the measurement point i = nw is obtained as the radar measurement cover thickness ds| _RC . a first recording means for acquiring the sheath reflected P-wave occurrence time _tp = _tp | _RC by replacing ds in the following equation with the radar-measured cover thickness ds| _RC ;

Ultrasonic waves are continuously transmitted from the transmission probe toward the sheath to be measured at predetermined time intervals, and each time the transmission is performed, the recorded waves obtained by the reception probe are averaged and received at each measurement point i. Wave G(t)| _{i=1 to nw} is obtained, and the received wave G(t)| _{i=1 to nw} is FFT-transformed to obtain the corresponding received wave spectrum F(f)| _{i=1 to nw.} a second recording means for
A sine shape in which the frequency between 0.0 and (f _s −Δf _s ) is “0.0” and the frequency between (f _s −Δf _s ) and f _s is “0.0 to 1.0” An increasing function, a sine-shaped decreasing function that is "1.0 to 0.0" between the frequency f _s and (f _s +Δf _s ), and is "0.0" above the frequency (f _s +Δf _s ) Let the function be the F3 filter function,
an operation receiving means for receiving an operator's operation for gradually moving the center frequency _fs of the F3(f) filter function to the low frequency side or the high frequency side;
Let Δt _k be a value set by the operator, "0.0" from time 0.0 to (t _p | _RC - Δt _k ), and "0.0" at time (t _p | _RC - Δt _k ). , a sine-shaped increasing function that becomes "1.0" at time t _p | _RC , and _a sin _- shaped increasing function that becomes "1.0" at time t _p | _RC and becomes "0.0" at time (t _p | A decreasing function, a function that becomes "0.0" after the time (t _p | _RC + Δt _k ) is defined as the time filter function TGC4(t), and each time the operation receiving means receives an operator's operation, the center frequency f For a time-series wave obtained by inverse FFT transforming the spectrum obtained by multiplying the received wave spectrum F(f) | _{i = 1 to nw} by the F3(f) filter function with _s , the time-series wave Multiply by the time filter function TGC4(t) whose central time is the time of occurrence of any measuring point i to obtain the primary reflection P-wave occurrence time t _p(1) | _{i = 1 to nw} for analysis. Then, replacing ds in the following equation with the primary cover thickness for analysis ds ₍₁₎ | _i , and replacing t _p in the following equation with the primary reflected P-wave occurrence time t _p(1) | _i for analysis, Acquire the primary cover thickness ds ₍₁₎ | _i for analysis,

Furthermore, when the primary cover thickness for analysis ds _{(1) |} t _{p (1)} | _i and _the primary cover thickness for analysis ds ( _{1 )} | When the point nB is set to i=nw and the primary cover thickness for analysis ds _{(1) | Occurrence} time _{t p} ( _{1 ) | The primary} cover thickness for analysis ds ₍₁₎ obtained by applying the P-wave occurrence time t _{p(1) |} The primary cover thickness ds ( _{1 )} for analysis obtained by applying _{the next} reflected P-wave occurrence time t p _{( 1)} | a first analysis means for obtaining a start station nA and an end station nB for each primary cover thickness ds ₍₁₎ | _large and ds ₍₁₎ | _small for
The center frequency f ₀ is 20 kHz, the frequency f _w is 50 kHz - Δf _w < f _w < 50 kHz + Δf _w (where Δf _w = 5 kHz) set by the operator, and the frequency f ₂ is 80 kHz. As a sin-shaped increasing function from frequency -10 kHz f ₀ is "0.0 to 1.0", a sin-shaped decreasing function from frequency f ₀ to f _w is "1.0 to 0.0", A sine-shaped increasing function from the frequency _fw to _f2 becomes "0.0 to 1.0", and a sine-shaped decreasing function from the frequency _f2 to ( _f2 +30kHz) becomes "1.0 to 0.0" , _the received wave spectrum _F (f _{) | _} a second analysis means for obtaining a time series GA(t) | _{i = 1 to nw + 1} for use ;
When the analytical primary cover thickness ds ₍₁₎ | _i in multi-point measurement of i = 1 to nw is the same, the analytical primary reflected P-wave occurrence time t _{p (1)} | _i is changed to t _{p ( 1)} , and the primary cover thickness for analysis ds _{(1 ) |} and a first processing means for determining the grout filling state of the sheath to be measured by analysis by the analysis means and the eighth analysis means;
When the analytical primary cover thickness ds ₍₁₎ | in multi-point measurement of i=1 to nw is different, the analytical primary reflected P-wave occurrence time t p _{( 1)} is changed to t _{p (1)} | _The third analysis means, the fourth analysis means, the fifth analysis means, and the sixth analysis in which the _primary cover thickness for analysis ds ₍₁₎ is replaced with ds ₍₁₎ | means, the seventh analysis means, and the eighth analysis means to determine the grout filling state of the sheath to be measured at _{the large} primary cover thickness for analysis ds ₍₁₎ | and,
Subsequent to the determination by the second processing means, the analysis primary reflected P-wave occurrence time _{tp(1) is reduced} to tp _{( 1)} | is replaced by ds ₍₁₎ | _small , the third analysis means, the fourth analysis means, the fifth analysis means, the sixth analysis means, the seventh analysis means, and the eighth a third processing means for determining the grout filling state of the sheath to be measured at _{the small} primary cover thickness for analysis ds ₍₁₎ | by analysis by the analysis means;
The third analysis means is
_The time _{series GA} (t )| _{i=1 to nw+1} are multiplied to obtain analysis cutout waves GB ₍₁₎ (t)| _{i=1 to nw+1} , and the analysis cutout waves GB ₍₁₎ (t)| _{i=1 to nw+1} are obtained by Analysis means for obtaining the corresponding spectrum FB ₍₁₎ (f) | _{i = 1 to nw + 1} by FFT transforming,
The time filter function TGC1(t) is
Assuming that reference time t _h = t _{p (1)} + Δt _h1 , a sine-shaped increasing line segment that becomes “0.0” at time t = 0 and “1.0” at reference time _t , time t = reference time t It is a function calculated by (TGCA (t)) ^ne using the TGCA (t) function in which _h and after is "1.0",
The time filter function TGC2(t) is
Assuming that the reference time _t = _tp(1) , the time t = t _h is "1.0" from the time t = 0.0, and the time t = the reference time _t is "1.0", and the time t = 400μ Function calculated by (TGCB(t)) ^nf and
The fourth analysis means is
The spectrum FB ( _{1 )} (f ₎ | Acquire the primary _spectrum for analysis FC _{( 1)} ( _f ) | ₍₁₎ (f) | primary time series GC for analysis corresponding to _{i = 1 to nw + 1 (1)} (t) |
The fifth analysis means is
Each time the trapezoidal window function A is moved from time t _start = t _{p (1)} - Δt _p1 to time t _end = t _{p (1)} + Δt _p2 at intervals of Δt _a , the primary time series for analysis GC ₍₁₎ (t)|A spectrum obtained by multiplying _{i=1 to nw+1} by a trapezoidal window function A to obtain a spectrum corresponding to the cut out time series, and normalizing the maximum spectrum value below the frequency _fw to 1.0. In the above, the maximum spectrum value at the frequency f _w or higher is set as the time sweep normalized spectrum value SP _f2 , and the time sweep normalized spectrum value SP _{f2 (1)} (t) | _{i = 1 to nw + 1} is created, and Time sweeps f ₀ and _{f 2 obtained} by comparing the maximum spectral values at the frequency fw _or higher and at the frequency fw or lower at each transition of time and normalizing the larger maximum spectral value to 1.0 Analysis means for creating a spectrum SP _f2(1) (f, t) ^nc | _{i=1 to nw+1} ,
The trapezoidal window function A is
With the reference time t as _{the beginning} and the value indicating the time width set according to the primary cover thickness for analysis ds ₍₁₎ or ds ₍₁₎ | _large or ds ₍₁₎ | _small as _{t a} , time t = "0.0 _" between 0.0 _and t-5, time t = sine-shaped increasing function from "0.0" to "1.0" from t-5 to t _-start , time t = sine-shaped decreasing function from t _start to t _start + t _a is "1.0", time t = t _start + t _a to t _start + t _a +5 is from "1.0" to "0.0", time t = t is a function in which _{the beginning} +t _a +5 and after is "0.0",
The sixth analysis means is
Using the start measurement point nA and the end measurement point nB obtained by the first analysis means, the time sweep normalized spectrum value SP _{f2 (1)} (t)| _i=nA~nB spectrum value at the station i=nA~n1 (where boundary station n1 ≤ end station nB), from time t _p(1) -Δt _B1 to time Characteristic TA, or time sweep criterion, by which said boundary station n1 is identified with an increasing trend between t _{p (1)} +Δt _B2 and confirming that the threshold α _σ is exceeded at time t p(1) +Δt _B2 spectral value SP _{f2(1) (} t ₎ | +Δt _B2 is less than the threshold value α _σ to identify which of the characteristic TBs the boundary survey point n1 is identified;
The seventh analysis means is
In the sixth analysis means, when the spectrum shape of the time sweep normalized spectral value SP _f2(1) (t)| _{i=nA to nB} is identified as the characteristic TA, the time sweep normalized spectral value SP _{f2(1 )} (t) | Based on _{i = nA to nB} , analysis is performed by the first TA processing means and the second TA processing means to determine the grout filling state,
The eighth analysis means is
In the sixth analysis means, when the spectrum shape of the time sweep normalized spectral value SP _f2(1) (t)| _{i=nA to nB} is identified as the characteristic TB, the time sweep normalized spectral value SP _{f2(1 )} (t) | Analysis means for determining the grout filling state by performing analysis by the first TB processing means and the second TB processing means based on _{i = nA to nB} ,
The first TA processing means of the seventh analysis means,
The time-swept normalized _spectrum value SP _{f2(1) ( t )} | +Δt _B2 , and when the threshold value α _σ is exceeded at time t _p(1) +Δt _B2 , the time sweep normalized spectrum value SP _f2(1) (t) | _{i=nA to n1} (where , n1≦nB), between time t _p(1) −Δt _B1 and time t _p(1) +Δt _B2 , let t _i be the time when the threshold value _ασ is exceeded, and let t _A be the average value of this and obtain Δt _A based on the following formula,

Acquire the analysis secondary reflection P-wave occurrence time t _{p (2)} based on the following formula,

ds in the following equation is replaced by the secondary cover thickness ds ₍₂₎ for analysis, and _tp in the following equation is replaced by the secondary reflection P-wave occurrence time _tp(2) for analysis, and the secondary cover thickness ds _{( 2)} to obtain

By replacing the analysis primary reflected P-wave occurrence time _tp(1) in the third analysis means and the fourth analysis means with the analysis secondary reflection P-wave occurrence time _tp(2) , the third analysis means, and the second analysis by the fourth analysis means, the analysis primary time series GC ₍₁₎ (t) | _{i = 1 to nw + 1} instead of the analysis secondary time series GC _{(2 )} ( _t ) _| Let t _p(2) −Δt _p1 of the trapezoidal window function A using the analysis secondary reflection P-wave occurrence time _{t p(2)} be the _start point time t, and t _p(2) +Δt _p2 be the end point time t _{apply the} time-swept normalized _spectrum values SP _{f2( 2 )} ⁽ t)| Create | _{i = 1 to nw + 1} , then recreate WAVE addition average wave GC ₍₂₎ (t) | _{i = nw + 1} with the following formula,

The spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 , and the ^spectrum FC ₍₂₎ (f) Create | _i=nw+1 ,

After changing the phase information of the spectrum ^FC ₍₂₎ (f)| _i=nw+1 to the phase information of the spectrum FC ₍₂₎ (f)| _i=nw+1 , the ^spectrum FC ₍₂₎ (f) | _{i = nw + 1 FFT} inverse transform to create SP addition average wave GC ^~ ₍₂₎ (t ₎ | -Δt _p1 is the _start point time t and t _{p (2) +} Δt _p2 is applied to the SP addition average wave GC ^~ ₍₂₎ ( _t ) | Time sweep normalized _spectrum value SP _{f2( 2 )} ( _t ) | After recreating _f2(2) (f, t) ^nc | _{i=nw+1 ,} time sweep normalized spectrum value SP _f2(2) (t)| Using _the value SP _{f2 (2) (} ^t )| =α _σ +0.06) value and the time set according to the secondary cover _thickness ds _{( 2)} for analysis. The acquired time-swept normalized spectral _value SP _{f2(2) (} t _{* )} ^| _i at time t _* is _“ unfilled ” ^, and when α ^~ _σ < SP _{f2 (2) (} t _* ) _| SP _f2(2) (t) | is processing means for displaying _{i=1 to nw+1} on a display unit,
The second TA processing means of the seventh analysis means,
_In the case of n1<nB, when the time-swept normalized spectral value SP _{f2(1) ( t )} | Further _time after time t _{p (1)} + Δt _B2 , the time sweep normalized spectrum value SP _{f2 (1)} ( _t ) _| Select the time t _i of the measuring point i that satisfies the following formula, and the average value of the time t _i is the time average value t _A ,

If there is no time t _i that satisfies the above formula, the time average value t _A = t _{M1 (1)} , and Δt _A is obtained by the following formula,

Obtaining the analysis secondary sheath reflection M ₁ wave occurrence time t _M1(2) and the analysis secondary reflection P wave occurrence time t _p(2) based on the following equation group,

Substituting ds in the following equation for the secondary cover thickness ds ₍₂₎ for analysis, and replacing _tp in the following equation for the secondary reflection P-wave occurrence time _tp(2) for analysis, the secondary cover thickness ds for analysis ₍₂₎ is obtained,

By replacing the analysis primary reflected P-wave occurrence time _tp(1) in the third analysis means and the fourth analysis means with the analysis secondary reflection P-wave occurrence time _tp(2) , the third analysis means, and the second analysis by the fourth analysis means, the analysis primary time series GC ₍₁₎ (t) | _{i = 1 to nw + 1} instead of the analysis secondary time series GC _{(2 )} ( _t ) _| Let t _p(2) −Δt _p1 of the trapezoidal window function A using the analysis secondary reflection P-wave occurrence time _{t p(2)} be the _start point time t, and t _p(2) +Δt _p2 be the end point time t _{apply the} time-swept normalized _spectrum values SP _{f2( 2 )} ⁽ t)| Create | _{i = 1 to nw + 1} , then recreate WAVE addition average wave GC ₍₂₎ (t) | _{i = nw + 1} with the following formula,

The spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 , and the ^spectrum FC ₍₂₎ (f) Create | _i=nw+1 ,

After changing the phase information of the spectrum ^FC ₍₂₎ (f)| _i=nw+1 to the phase information of the spectrum FC ₍₂₎ (f)| _i=nw+1 , the ^spectrum FC ₍₂₎ (f) | _{i = nw + 1 FFT} inverse transform to create SP addition average wave GC ^~ ₍₂₎ (t ₎ | -Δt _p1 is the _start point time t and t _{p (2) +} Δt _p2 is applied to the SP addition average wave GC ^~ ₍₂₎ ( _t ) | Time _- swept normalized _spectrum value SP _{f2(2) ( t} ) | After recreating SP _{f2(2 ) (} f, _t ) ^nc | Spectral _value SP _{f2 (2)} ⁽ _t ) | (=α _σ +0.06) and the time set according to the secondary cover thickness ds ( _{2 )} for analysis is used as the _* value. _The time-swept normalized spectral value SP _{f2(2) ( t * )} ^| _i at time t _* obtained by A processing means for automatically making a judgment and displaying the judgment result and the time-swept normalized spectrum value SP _f2(2) (t) | _{i = 1 to nw + 1} on the display unit,
The first TB processing means of the eighth analysis means,
If the time-swept normalized spectral value SP _f2(1) (t)| _i falls below the threshold α _σ at time t _p(1) +Δt _B2 for each station i=nA to n1 (where n1≦nB), At a further time after time t _p(1) +Δt _B2 , the time-swept normalized spectrum value SP _f2(1) (t)| _i is the threshold value _ασ , and select the time t _i at the measuring point _i that satisfies the following equation, and the average value of the time t _i is the time average value t _A ,

If there is no time t _i that satisfies the above formula, the time average value t _A = t _{M1 (1)} , and Δt _A is obtained by the following formula,

Obtaining the analysis secondary sheath reflection M ₁ wave occurrence time t _M1(2) and the analysis secondary reflection P wave occurrence time t _p(2) based on the following equation group,

Substituting ds in the following equation for the secondary cover thickness ds ₍₂₎ for analysis, and replacing _tp in the following equation for the secondary reflection P-wave occurrence time _tp(2) for analysis, the secondary cover thickness ds for analysis ₍₂₎ is obtained,

By replacing the analysis primary reflected P-wave occurrence time _tp(1) in the third analysis means and the fourth analysis means with the analysis secondary reflection P-wave occurrence time _tp(2) , the third analysis means, and the second analysis by the fourth analysis means, the analysis primary time series GC ₍₁₎ (t) | _{i = 1 to nw + 1} instead of the analysis secondary time series GC _{(2 )} ( _t ) _| Let t _p(2) −Δt _p1 of the trapezoidal window function A using the analysis secondary reflection P-wave occurrence time _{t p(2)} be the _start point time t, and t _p(2) +Δt _p2 be the end point time t _{apply the} time-swept normalized _spectrum values SP _{f2( 2 )} ⁽ t)| Create | _{i = 1 to nw + 1} , then recreate WAVE addition average wave GC ₍₂₎ (t) | _{i = nw + 1} with the following formula,

The spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 , and the ^spectrum FC ₍₂₎ (f) Create | _i=nw+1 ,

After changing the phase information of the spectrum ^FC ₍₂₎ (f)| _i=nw+1 to the phase information of the spectrum FC ₍₂₎ (f)| _i=nw+1 , the ^spectrum FC ₍₂₎ (f) | _{i = nw + 1 FFT} inverse transform to create SP addition average wave GC ^~ ₍₂₎ (t ₎ | -Δt _p1 is the _start point time t and t _{p (2) +} Δt _p2 is applied to the SP addition average wave GC ^~ ₍₂₎ ( _t ) | Time sweep normalized _spectrum value SP _{f2( 2 )} ( _t ) | After recreating _f2(2) (f, t) ^nc | _{i=nw+1 ,} time sweep normalized spectrum value SP _f2(2) (t)| Using _the value SP _{f2 (2) (} ^t )| =α _σ +0.06) value and the time set according to the secondary cover _thickness ds _{( 2)} for analysis. The acquired time-swept normalized spectral _value SP _f2(2) (t _* )| _i at time t _* is automatically labeled as “ ^fully filled” if SP _f2(2) (t _{* )} | A processing means for determining and displaying the determination result and the time-swept standardized spectrum value SP _f2(2) (t) | _{i=1 to nw+1} on the display unit,
The second TB processing means of the eighth analysis means,
In the case of n1<nB _, the time-swept normalized spectrum value SP _{f2(1) ( t ) |} When the threshold value α _σ is exceeded at time t _p(1) +Δt _B2 , the time sweep normalized spectrum value SP _f2(1) (t) | _i=n1+1 to time t _p(1) − Let t i be the time when the threshold value α _σ is exceeded between Δt _B1 and time t _p(1) +Δt _B2 , and obtain the time average value _{t A ,} which is the average value of time t _i for each measurement point i, and use the following formula: and obtaining Δt _A based on

Acquire the analysis secondary reflection P-wave occurrence time t _{p (2)} based on the following formula,

Substituting ds in the following equation for the secondary cover thickness ds ₍₂₎ for analysis, and replacing _tp in the following equation for the secondary reflection P-wave occurrence time _tp(2) for analysis, the secondary cover thickness ds for analysis ₍₂₎ is obtained,

By replacing the analysis primary reflected P-wave occurrence time _tp(1) in the third analysis means and the fourth analysis means with the analysis secondary reflection P-wave occurrence time _tp(2) , the third analysis means, and the second analysis by the fourth analysis means, the analysis primary time series GC ₍₁₎ (t) | _{i = 1 to nw + 1} instead of the analysis secondary time series GC _{(2 )} ( _t ) _| Let t _p(2) −Δt _p1 of the trapezoidal window function A using the analysis secondary reflection P-wave occurrence time _{t p(2)} be the _start point time t, and t _p(2) +Δt _p2 be the end point time t _{apply the} time-swept normalized _spectrum values SP _{f2( 2 )} ⁽ t)| Create | _{i = 1 to nw + 1} , then recreate WAVE addition average wave GC ₍₂₎ (t) | _{i = nw + 1} with the following formula,

The spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 , and the ^spectrum FC ₍₂₎ (f) Create | _i=nw+1 ,

After changing the phase information of the spectrum ^FC ₍₂₎ (f)| _i=nw+1 to the phase information of the spectrum FC ₍₂₎ (f)| _i=nw+1 , the spectrum ^FC ₍₂₎ (f)| SP addition average wave GC ^~ ( _{2 ) (} t ₎ | A sweep process with Δt _p1 as the _start point time t and t _{p (2)} + Δt _p2 as the _end point time t is applied to the SP addition average wave GC ^~ ₍₂₎ ( _t ) | Time _sweep normalized _{spectrum value} SP _{f2(2) ( t} ) | ₍₂₎ After recreating (f, t) ^nc | _i=nw+1 , the time sweep normalized spectrum value SP _f2(2) (t) | _{i=n1+1 to nB} and the time sweep normalized spectrum value of SP addition SP f2 _{( 2)} ( _t ) ^| α _σ +0.06) value and the time set according to the secondary cover thickness ds ₍₂₎ for analysis is obtained using an empty determination cursor t _* = t _{p (2)} + * Time-swept normalized _spectral value SP _{f2(2) (} t _{* )} ^| _i at time t _{* is} “unfilled” when Automatically determine, and when α ^~ _σ < SP _{f2 (2)} (t _* ) | _i ≤ α ^~ _σ + 0.18, automatically determine “insufficient filling”, the determination result and the time sweep normalized spectrum value SP _{f2 (2)} (t) | A non-destructive inspection device that is processing means for displaying _{i=1 to nw+1} on the display unit. The second analysis means is
Replacing the A _K (f) filter function with the A _G (f) ^nG filter function, the analysis spectrum FA (f) _| )| is a means for obtaining _i ,
The A _G (f) ^nG filter function is
(f _w + f ₂ ^~ ) / 2 (however, f ₂ ^~ = 80 kHz) is the frequency f _k , the frequency f = 0.0 is "0.0", and the frequency f _k is "1.0" a sine-shaped increasing function that becomes "1.0" at the frequency f _k and a sine-shaped decreasing function that becomes "0.0" at the frequency f _k ×2, and above the frequency f _k ×2 is a function that becomes "0.0",
The nG value of the A _G (f) ^nG filter function is
The _{analysis spectrum} FA ₍ f _{) | i} is the value when the maximum spectrum value is obtained between the frequency f _w ~ frequency f ₂ ^~ = 80 kHz at any of the measurement points i,
The fourth analysis means is
The maximum spectrum value at the frequency _{fw or less} is normalized to _1.0 for each spectrum FB(f) | Means for setting the spectral value to the threshold value α _σ ,
The fifth analysis means is
of the time sweep normalized spectrum value SP _f2(1) (t)| _{i=1 to nw+1} and the time sweep f ₀ , f ₂ spectrum SP _f2(1) (f, _t ) ^nc | Instead, _the time-swept normalized _spectrum values SP _f1,2 ( _{1 )} (t) _| , t) means for creating ^nc | _{i=1 to nw+1} ,
The sixth analysis means is
specifying whether the spectral values of the time-swept normalized spectral values SP _f1,2(1) (t)| _{i=nA to nB} are the characteristic TA or the characteristic TB, and is a means of identifying
The seventh analysis means and the eighth analysis means are
Instead of the time sweep normalized spectrum _value SP _f2(2) (t)| _i and the time sweep f ₀ , f ₂ spectrum SP _f2(2) (f, t) ^nc | Spectral value SP _f1,2(2) (t)| _i and time sweep f ₀ , (f ₁ to f ₂ ) spectrum SP _f1,2(2) (f, t) ^nc _| Instead of the time-swept normalized spectral value SP _f2(2) (t _{* )} | _i at t _* , the time-swept normalized spectral value SP _f1,2(2) (t _* )| 2. The non-destructive inspection apparatus according to claim 1, which is a means for determining the grout filling state by obtaining _i . It has a pair of probes consisting of a transmitting probe that transmits ultrasonic waves and a receiving probe that receives ultrasonic waves, and a display unit that displays at least various information, and analyzes the grout filling state of the sheath to be measured. A non-destructive inspection method using an apparatus equipped with an analysis device for determining,
The analysis equipment is
an input receiving step of receiving input of concrete longitudinal wave sound velocity, cover thickness of the second sheath, plate thickness, and path length of the bottom corner of the plate thickness, which are operated by the operator;
On the virtual line segment of the concrete surface along the longitudinal direction of the sheath to be measured that passes through the intersection of the concrete surface and the perpendicular line from the cross-sectional center of the sheath to be measured to the concrete surface, measuring points i = 1 to nw (however, , nw>1) are measured in order, and the average value of the sheath cover thickness at the measurement point i = 1 and the sheath cover thickness at the measurement point i = nw is obtained as the radar measurement cover thickness ds| _RC . a first recording step of replacing ds in the following equation with the radar-measured cover thickness ds| _RC to acquire the sheath reflected P-wave occurrence time _tp = _tp | _RC ;

Ultrasonic waves are continuously transmitted from the transmission probe toward the sheath to be measured at predetermined time intervals, and each time the transmission is performed, the recorded waves obtained by the reception probe are averaged and received at each measurement point i. Wave G(t)| _{i=1 to nw} is obtained, and the received wave G(t)| _{i=1 to nw} is FFT-transformed to obtain the corresponding received wave spectrum F(f)| _{i=1 to nw.} a second recording step to
A sine shape in which the frequency between 0.0 and (f _s −Δf _s ) is “0.0” and the frequency between (f _s −Δf _s ) and f _s is “0.0 to 1.0” An increasing function, a sine-shaped decreasing function that is "1.0 to 0.0" between the frequency f _s and (f _s +Δf _s ), and is "0.0" above the frequency (f _s +Δf _s ) an operation receiving step of receiving an operator's operation to gradually move the center frequency _fs of the F3(f) filter function to the low frequency side or the high frequency side, with the function as the F3 filter function;
Let Δt _k be a value set by the operator, "0.0" from time 0.0 to (t _p | _RC - Δt _k ), and "0.0" at time (t _p | _RC - Δt _k ). , a sine-shaped increasing function that becomes "1.0" at time t _p | _RC , and a sin _- shaped increasing function _that becomes "1.0" at time t _p | _RC and becomes "0.0" at time (t _p | A decreasing function, a function that becomes "0.0" after the time (t _p | _RC + Δt _k ) is set as the time filter function TGC4(t), and each time an operator's operation is received in the operation receiving step, the center frequency f For a time-series wave obtained by inverse FFT transforming the spectrum obtained by multiplying the received wave spectrum F(f) | _{i = 1 to nw} by the F3(f) filter function with _s , the time-series wave Multiply by the time filter function TGC4(t) whose central time is the time of occurrence of any measuring point i to obtain the primary reflection P-wave occurrence time t _p(1) | _{i = 1 to nw} for analysis. Then, replacing ds in the following equation with the primary cover thickness for analysis ds ₍₁₎ | _i , and replacing t _p in the following equation with the primary reflected P-wave occurrence time t _p(1) | _i for analysis, Acquire the primary cover thickness ds ₍₁₎ | _i for analysis,

Furthermore, when the primary cover thickness for analysis ds _{(1) |} t _{p (1)} | _i and _the primary cover thickness for analysis ds ( _{1 )} | When the point nB is set to i=nw and the primary cover thickness for analysis ds _{(1) | Occurrence} time _{t p} ( _{1 ) | The primary} cover thickness for analysis ds ₍₁₎ obtained by applying the P-wave occurrence time t _{p(1) |} The primary cover thickness ds ( _{1 )} for analysis obtained by applying _{the next} reflected P-wave occurrence time t p _{( 1)} | a first analysis step of obtaining a starting station nA and an ending station nB for each primary cover thickness ds ₍₁₎ | _large and ds ₍₁₎ | _small for
The center frequency f ₀ is 20 kHz, the frequency f _w is 50 kHz - Δf _w < f _w < 50 kHz + Δf _w (where Δf _w = 5 kHz) set by the operator, and the frequency f ₂ is 80 kHz. As a sin-shaped increasing function from frequency -10 kHz f ₀ is "0.0 to 1.0", a sin-shaped decreasing function from frequency f ₀ to f _w is "1.0 to 0.0", A sine-shaped increasing function from the frequency _fw to _f2 becomes "0.0 to 1.0", and a sine-shaped decreasing function from the frequency _f2 to ( _f2 +30kHz) becomes "1.0 to 0.0" , _the received wave spectrum _F (f _{) | _} a second analysis step of obtaining time series GA(t) | _{i=1 to nw+1} for
When the analytical primary cover thickness ds ₍₁₎ | _i in multi-point measurement of i = 1 to nw is the same, the analytical primary reflected P-wave occurrence time t _{p (1)} | _i is changed to t _{p ( 1)} , and the primary cover thickness for analysis ds _{(1 ) |} A first processing step of determining the grout filling state of the sheath to be measured by the analysis step of and the analysis by the eighth analysis step;
When the analytical primary cover thickness ds ₍₁₎ | in multi-point measurement of i=1 to nw is different, the analytical primary reflected P-wave occurrence time t p _{( 1)} is changed to t _{p (1)} | In _addition , the third analysis step, the fourth analysis step, the fifth analysis step, and the sixth analysis in which the _primary cover thickness ds ₍₁₎ for analysis is replaced with ds ₍₁₎ | a second processing step of determining the grout filling state of the sheath to be measured at _{the large} primary cover thickness ds ₍₁₎ | and,
Subsequent to the determination in the second processing step, the analysis primary reflected P-wave occurrence time _{tp(1) is reduced} to _{tp(1) |} is replaced by ds ₍₁₎ | _small , the third analysis step, the fourth analysis step, the fifth analysis step, the sixth analysis step, the seventh analysis step, and the eighth a third processing step of determining the grout filling state of the measurement target sheath at _{the small} primary cover thickness ds ₍₁₎ | for analysis by the analysis in the analysis step;
The third analysis step is
_The time _{series GA} (t )| _{i=1 to nw+1} are multiplied to obtain analysis cutout waves GB ₍₁₎ (t)| _{i=1 to nw+1} , and the analysis cutout waves GB ₍₁₎ (t)| _{i=1 to nw+1} are obtained by An analysis step of obtaining the corresponding spectrum FB ₍₁₎ (f) | _{i = 1 to nw + 1} by FFT transforming,
The time filter function TGC1(t) is
Assuming that reference time t _h = t _{p (1)} + Δt _h1 , a sine-shaped increasing line segment that becomes “0.0” at time t = 0 and “1.0” at reference time _t , time t = reference time t It is a function calculated by (TGCA (t)) ^ne using the TGCA (t) function in which _h and after is "1.0",
The time filter function TGC2(t) is
Assuming that the reference time _t = _tp(1) , the time t = t _h is "1.0" from the time t = 0.0, and the time t = the reference time _t is "1.0", and the time t = 400μ Function calculated by (TGCB(t)) ^nf and
The fourth analysis step is
The spectrum FB ( _{1 )} (f ₎ | Acquire the primary spectrum for _analysis FC _{( 1)} ( _f ) | ₍₁₎ (f) | first-order time series GC for analysis corresponding to _{i = 1 to nw + 1 (1)} (t) |
The fifth analysis step is
Each time the trapezoidal window function A is moved from time t _start = t _{p (1)} - Δt _p1 to time t _end = t _{p (1)} + Δt _p2 at intervals of Δt _a , the primary time series for analysis GC ₍₁₎ (t)|A spectrum obtained by multiplying _{i=1 to nw+1} by a trapezoidal window function A to obtain a spectrum corresponding to the cut out time series, and normalizing the maximum spectrum value below the frequency _fw to 1.0. In the above, the maximum spectrum value at the frequency f _w or higher is set as the time sweep normalized spectrum value SP _f2 , and the time sweep normalized spectrum value SP _{f2 (1)} (t) | _{i = 1 to nw + 1} is created, and Time sweeps f ₀ and _{f 2 obtained} by comparing the maximum spectral values at the frequency fw _or higher and at the frequency fw or lower at each transition of time and normalizing the larger maximum spectral value to 1.0 an analysis step of creating a spectrum SP _f2(1) (f, t) ^nc | _{i=1 to nw+1} ,
The trapezoidal window function A is
With the reference time t as _{the beginning} and the value indicating the time width set according to the primary cover thickness for analysis ds ₍₁₎ or ds ₍₁₎ | _large or ds ₍₁₎ | _small as _{t a} , time t = "0.0 _" between 0.0 _and t-5, time t = sine-shaped increasing function from "0.0" to "1.0" from t-5 to t _-start , time t = sine-shaped decreasing function from t _start to t _start + t _a is "1.0", time t = t _start + t _a to t _start + t _a +5 is from "1.0" to "0.0", time t = t is a function in which _{the beginning} +t _a +5 and after is "0.0",
The sixth analysis step is
Using the start measurement point nA and the end measurement point nB obtained in the first analysis step, the time sweep normalized spectrum value SP _{f2 (1)} (t)| _i=nA~nB spectrum value at the station i=nA~n1 (where boundary station n1 ≤ end station nB), from time t _p(1) -Δt _B1 to time Characteristic TA, or time sweep criterion, by which said boundary station n1 is identified with an increasing trend between t _{p (1)} +Δt _B2 and confirming that the threshold α _σ is exceeded at time t p(1) +Δt _B2 spectral value SP _{f2(1) (} t ₎ | an analysis step of identifying which characteristic TB the boundary station n1 is identified by confirming that +Δt _B2 is below the threshold α _σ ;
The seventh analysis step is
In the sixth analysis step, when the spectral shape of the time sweep normalized spectral value SP _f2(1) (t) | _{i=nA to nB} is identified as the characteristic TA, the time sweep normalized spectral value SP _{f2(1 )} (t) | Based on _{i = nA to nB} , an analysis step of performing analysis by the first TA treatment step and the second TA treatment step to determine the grout filling state,
The eighth analysis step is
In the sixth analysis step, when the spectral shape of the time sweep normalized spectral value SP _f2(1) (t) | _{i = nA to nB} is identified as the characteristic TB, the time sweep normalized spectral value SP _{f2(1 )} (t) | An analysis step of performing analysis by the first TB treatment step and the second TB treatment step based on _{i = nA to nB} to determine the grout filling state,
The first TA treatment step of the seventh analysis step is
The time-swept normalized _spectrum value SP _{f2(1) ( t )} | +Δt _B2 , and when the threshold value α _σ is exceeded at time t _p(1) +Δt _B2 , the time sweep normalized spectrum value SP _f2(1) (t) | _{i=nA to n1} (where , n1≦nB), between time t _p(1) −Δt _B1 and time t _p(1) +Δt _B2 , let t _i be the time when the threshold value _ασ is exceeded, and let t _A be the average value of this and obtain Δt _A based on the following formula,

Acquire the analysis secondary reflection P-wave occurrence time t _{p (2)} based on the following formula,

ds in the following equation is replaced by the secondary cover thickness ds ₍₂₎ for analysis, and _tp in the following equation is replaced by the secondary reflection P-wave occurrence time _tp(2) for analysis, and the secondary cover thickness ds _{( 2)} to obtain

By replacing the analysis primary reflected P-wave occurrence time _tp(1) in the third analysis step and the fourth analysis step with the analysis secondary reflected P-wave occurrence time _tp(2) , the third analysis step, and the analysis again by the fourth analysis step, the analysis primary time series GC ₍₁₎ (t) | _{i = 1 to nw + 1} instead of the analysis secondary time series GC _{(2 ) (} t) _| Let t _p(2) −Δt _p1 of the trapezoidal window function A using the analysis secondary reflection P-wave occurrence time _{t p(2)} be the _start point time t, and t _p(2) +Δt _p2 be the end point time t _{apply the} time-swept normalized _spectrum values SP _{f2( 2 )} ⁽ t)| Create | _{i = 1 to nw + 1} , then recreate WAVE addition average wave GC ₍₂₎ (t) | _{i = nw + 1} with the following formula,

The spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 , and the ^spectrum FC ₍₂₎ (f) Create | _i=nw+1 ,

After changing the phase information of the spectrum ^FC ₍₂₎ (f)| _i=nw+1 to the phase information of the spectrum FC ₍₂₎ (f)| _i=nw+1 , the ^spectrum FC ₍₂₎ (f) SP addition average wave GC ^~ ₍₂₎ (t) | i _{= nw + 1} is created by inverse FFT of | _{i = nw + 1} , and t _{p (2)} of the trapezoidal window function A by the fifth analysis step again. -Δt _p1 is the _start point time t and t _{p (2) +} Δt _p2 is applied to the SP addition average wave GC ^~ ₍₂₎ ( _t ) | Time sweep normalized _spectrum value SP _{f2( 2 )} ( _t ) | After recreating _f2(2) (f, t) ^nc | _{i=nw+1 ,} time sweep normalized spectrum value SP _f2(2) (t)| Using _the value SP _{f2 (2) (} ^t )| =α _σ +0.06) value and the time set according to the secondary cover _thickness ds _{( 2)} for analysis. The acquired time-swept normalized spectral _value SP _{f2(2) (} t _{* )} ^| _i at time t _* is _“ unfilled ” ^, and when α ^~ _σ < SP _{f2 (2) (} t _* ) _| SP _f2(2) (t) | A processing step for displaying _{i=1 to nw+1} on the display unit,
The second TA treatment step of the seventh analysis step is
_In the case of n1<nB, when the time-swept normalized spectral value SP _{f2(1) ( t )} | Further _time after time t _{p (1)} + Δt _B2 , the time sweep normalized spectrum value SP _{f2 (1)} ( _t ) _| Select the time t _i of the measuring point i that satisfies the following formula, and the average value of the time t _i is the time average value t _A ,

If there is no time t _i that satisfies the above formula, the time average value t _A = t _{M1 (1)} , and Δt _A is obtained by the following formula,

Obtaining the analysis secondary sheath reflection M ₁ wave occurrence time t _M1(2) and the analysis secondary reflection P wave occurrence time t _p(2) based on the following equation group,

Substituting ds in the following equation for the secondary cover thickness ds ₍₂₎ for analysis, and replacing _tp in the following equation for the secondary reflection P-wave occurrence time _tp(2) for analysis, the secondary cover thickness ds for analysis ₍₂₎ is obtained,

By replacing the analysis primary reflected P-wave occurrence time _tp(1) in the third analysis step and the fourth analysis step with the analysis secondary reflected P-wave occurrence time _tp(2) , the third analysis step, and the analysis again by the fourth analysis step, the analysis primary time series GC ₍₁₎ (t) | _{i = 1 to nw + 1} instead of the analysis secondary time series GC _{(2 ) (} t) _| Let t _p(2) −Δt _p1 of the trapezoidal window function A using the analysis secondary reflection P-wave occurrence time _{t p(2)} be the _start point time t, and t _p(2) +Δt _p2 be the end point time t _{apply the} time-swept normalized _spectrum values SP _{f2( 2 )} ⁽ t)| Create | _{i = 1 to nw + 1} , then recreate WAVE addition average wave GC ₍₂₎ (t) | _{i = nw + 1} with the following formula,

The spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 , and the ^spectrum FC ₍₂₎ (f) Create | _i=nw+1 ,

After changing the phase information of the spectrum ^FC ₍₂₎ (f)| _i=nw+1 to the phase information of the spectrum FC ₍₂₎ (f)| _i=nw+1 , the ^spectrum FC ₍₂₎ (f) SP addition average wave GC ^~ ₍₂₎ (t) | i _{= nw + 1} is created by inverse FFT of | _{i = nw + 1} , and t _{p (2)} of the trapezoidal window function A by the fifth analysis step again. -Δt _p1 is the _start point time t and t _{p (2) +} Δt _p2 is applied to the SP addition average wave GC ^~ ₍₂₎ ( _t ) | Time _- swept normalized _spectrum value SP _{f2(2) ( t} ) | After recreating SP _{f2(2 ) (} f, _t ) ^nc | Spectral _value SP _{f2 (2)} ⁽ _t ) | (=α _σ +0.06) and the time set according to the secondary cover thickness ds ( _{2 )} for analysis is used as the _* value. _The time-swept normalized spectral value SP _{f2(2) ( t * )} ^| _i at time t _* obtained by A processing step of automatically determining and displaying the determination result and the time-swept standardized spectral value SP _f2(2) (t) | _{i = 1 to nw + 1} on the display unit,
The first TB processing step of the eighth analysis step includes
If the time-swept normalized spectral value SP _f2(1) (t)| _i falls below the threshold α _σ at time t _p(1) +Δt _B2 for each station i=nA to n1 (where n1≦nB), At a further time after time t _p(1) +Δt _B2 , the time-swept normalized spectrum value SP _f2(1) (t)| _i is the threshold value _ασ , and select the time t _i at the measuring point _i that satisfies the following equation, and the average value of the time t _i is the time average value t _A ,

If there is no time t _i that satisfies the above formula, the time average value t _A = t _{M1 (1)} , and Δt _A is obtained by the following formula,

Obtaining the analysis secondary sheath reflection M ₁ wave occurrence time t _M1(2) and the analysis secondary reflection P wave occurrence time t _p(2) based on the following equation group,

Substituting ds in the following equation for the secondary cover thickness ds ₍₂₎ for analysis, and replacing _tp in the following equation for the secondary reflection P-wave occurrence time _tp(2) for analysis, the secondary cover thickness ds for analysis ₍₂₎ is obtained,

By replacing the analysis primary reflected P-wave occurrence time _tp(1) in the third analysis step and the fourth analysis step with the analysis secondary reflected P-wave occurrence time _tp(2) , the third analysis step, and the analysis again by the fourth analysis step, the analysis primary time series GC ₍₁₎ (t) | _{i = 1 to nw + 1} instead of the analysis secondary time series GC _{(2 ) (} t) _| Let t _p(2) −Δt _p1 of the trapezoidal window function A using the analysis secondary reflection P-wave occurrence time _{t p(2)} be the _start point time t, and t _p(2) +Δt _p2 be the end point time t _{apply the} time-swept normalized _spectrum values SP _{f2( 2 )} ⁽ t)| Create | _{i = 1 to nw + 1} , then recreate WAVE addition average wave GC ₍₂₎ (t) | _{i = nw + 1} with the following formula,

The spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 , and the ^spectrum FC ₍₂₎ (f) Create | _i=nw+1 ,

After changing the phase information of the spectrum ^FC ₍₂₎ (f)| _i=nw+1 to the phase information of the spectrum FC ₍₂₎ (f)| _i=nw+1 , the ^spectrum FC ₍₂₎ (f) SP addition average wave GC ^~ ₍₂₎ (t) | i _{= nw + 1} is created by inverse FFT of | _{i = nw + 1} , and t _{p (2)} of the trapezoidal window function A by the fifth analysis step again. -Δt _p1 is the _start point time t and t _{p (2) +} Δt _p2 is applied to the SP addition average wave GC ^~ ₍₂₎ ( _t ) | Time sweep normalized _spectrum value SP _{f2( 2 )} ( _t ) | After recreating _f2(2) (f, t) ^nc | _{i=nw+1 ,} time sweep normalized spectrum value SP _f2(2) (t)| Using _the value SP _{f2 (2) (} ^t )| =α _σ +0.06) value and the time set according to the secondary cover _thickness ds _{( 2)} for analysis. The acquired time-swept normalized spectral _value SP _f2(2) (t _* )| _i at time t _* is automatically labeled as “ ^fully filled” if SP _f2(2) (t _{* )} | A processing step of determining and displaying the determination result and the time sweep normalized spectral value SP _f2(2) (t) | _{i = 1 to nw + 1} on the display unit,
The second TB processing step of the eighth analysis step includes
In the case of n1<nB _, the time-swept normalized spectrum value SP _{f2(1) ( t ) |} When the threshold value α _σ is exceeded at time t _p(1) +Δt _B2 , the time sweep normalized spectrum value SP _f2(1) (t) | _i=n1+1 to time t _p(1) − Let t i be the time when the threshold value α _σ is exceeded between Δt _B1 and time t _p(1) +Δt _B2 , and obtain the time average value _{t A ,} which is the average value of time t _i for each measurement point i, and use the following formula: and obtaining Δt _A based on

Acquire the analysis secondary reflection P-wave occurrence time t _{p (2)} based on the following formula,

Substituting ds in the following equation for the secondary cover thickness ds ₍₂₎ for analysis, and replacing _tp in the following equation for the secondary reflection P-wave occurrence time _tp(2) for analysis, the secondary cover thickness ds for analysis ₍₂₎ is obtained,

By replacing the analysis primary reflected P-wave occurrence time _tp(1) in the third analysis step and the fourth analysis step with the analysis secondary reflected P-wave occurrence time _tp(2) , the third analysis step, and the analysis again by the fourth analysis step, the analysis primary time series GC ₍₁₎ (t) | _{i = 1 to nw + 1} instead of the analysis secondary time series GC _{(2 ) (} t) _| Let t _p(2) −Δt _p1 of the trapezoidal window function A using the analysis secondary reflection P-wave occurrence time _{t p(2)} be the _start point time t, and t _p(2) +Δt _p2 be the end point time t _{apply the} time-swept normalized _spectrum values SP _{f2( 2 )} ⁽ t)| Create | _{i = 1 to nw + 1} , then recreate WAVE addition average wave GC ₍₂₎ (t) | _{i = nw + 1} with the following formula,

The spectrum FC ₍₂₎ (f)| _i=nw+1 is obtained by the FFT conversion of the WAVE addition average wave GC ₍₂₎ (t)| _i=nw+1 , and the ^spectrum FC ₍₂₎ (f) Create | _i=nw+1 ,

After changing the phase information of the spectrum ^FC ₍₂₎ (f)| _i=nw+1 to the phase information of the spectrum FC ₍₂₎ (f)| _i=nw+1 , the spectrum ^FC ₍₂₎ (f)| Create SP addition average wave GC ^~ ( _{2 ) (} t ₎ | A sweep process with Δt _p1 as the _start point time t and t _{p (2)} + Δt _p2 as the _end point time t is applied to the SP addition average wave GC ^~ ₍₂₎ ( _t ) | Time _sweep normalized _{spectrum value} SP _{f2(2) ( t} ) | ₍₂₎ After recreating (f, t) ^nc | _i=nw+1 , the time sweep normalized spectrum value SP _f2(2) (t) | _{i=n1+1 to nB} and the time sweep normalized spectrum value of SP addition SP f2 _{( 2)} ( _t ) ^| α _σ +0.06) value and the time set according to the secondary cover thickness ds ₍₂₎ for analysis is obtained using an empty determination cursor t _* = t _{p (2)} + * Time-swept normalized _spectral value SP _{f2(2) (} t _{* )} ^| _i at time t _{* is} “unfilled” when Automatically determine, and when α ^~ _σ < SP _{f2 (2)} (t _* ) | _i ≤ α ^~ _σ + 0.18, automatically determine “insufficient filling”, the determination result and the time sweep normalized spectrum value SP _{f2 (2)} (t) | A non-destructive inspection method, which is a processing step for displaying _{i=1 to nw+1} on the display unit. The second analysis step includes
Replacing the A _K (f) filter function with the A _G (f) ^nG filter function, the analysis spectrum FA (f) _| ) _|
The A _G (f) ^nG filter function is
(f _w + f ₂ ^~ ) / 2 (however, f ₂ ^~ = 80 kHz) is the frequency f _k , the frequency f = 0.0 is "0.0", and the frequency f _k is "1.0" a sine-shaped increasing function that becomes "1.0" at the frequency f _k and a sine-shaped decreasing function that becomes "0.0" at the frequency f _k ×2, and above the frequency f _k ×2 is a function that becomes "0.0",
The nG value of the A _G (f) ^nG filter function is
The analysis _{spectrum FA} ( _{f ) | i} is the value when the maximum spectrum value is obtained between the frequency f _w ~ frequency f ₂ ^~ = 80 kHz at any of the measurement points i,
The fourth analysis step is
For each _spectrum FB ₍ f ₎ | A step of setting the spectral value to the threshold value α _σ ,
The fifth analysis step is
of the time sweep normalized spectrum value SP _f2(1) (t)| _{i=1 to nw+1} and the time sweep f ₀ , f ₂ spectrum SP _f2(1) (f, _t ) ^nc | Instead, _the time-swept normalized _spectrum values SP f1,2 _{( 1 )} (t) _| , t) creating ^nc | _{i=1 to nw+1} ,
The sixth analysis step is
specifying whether the spectral values of the time-swept normalized spectral values SP _f1,2(1) (t)| _{i=nA to nB} are the characteristic TA or the characteristic TB, and is a step of identifying
The seventh analysis step and the eighth analysis step are
Instead of the time sweep normalized spectrum _value SP _f2(2) (t)| _i and the time sweep f ₀ , f ₂ spectrum SP _f2(2) (f, t) ^nc | Spectral value SP _f1,2(2) (t)| _i and time sweep f ₀ , (f ₁ to f ₂ ) spectrum SP _f1,2(2) (f, t) ^nc _| Instead of the time-swept normalized spectral value SP _f2(2) (t _{* )} | _i at t _* , the time-swept normalized spectral value SP _f1,2(2) (t _* )| 4. The non-destructive inspection method according to claim 3, which is a step of determining the grout filling state by obtaining _i .

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