JP2543778B2 - Ground liquefaction prevention device - Google Patents
Ground liquefaction prevention deviceInfo
- Publication number
- JP2543778B2 JP2543778B2 JP2144451A JP14445190A JP2543778B2 JP 2543778 B2 JP2543778 B2 JP 2543778B2 JP 2144451 A JP2144451 A JP 2144451A JP 14445190 A JP14445190 A JP 14445190A JP 2543778 B2 JP2543778 B2 JP 2543778B2
- Authority
- JP
- Japan
- Prior art keywords
- ground
- liquefaction
- computer
- prevention device
- sensor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
- Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は例えば護岸部周辺地盤の如き、地下水位が高
く、液状化の可能性のある地盤の液状化防止装置に係る
ものである。Description: TECHNICAL FIELD The present invention relates to a liquefaction prevention device for ground, such as ground around a seawall, which has a high groundwater level and is likely to be liquefied.
（従来の技術） 地震時に地盤が液化したか否かを判定するためには目
視調査による方法と、土圧計及び間隙水圧計、並にそれ
らの増幅器、記録器を使用した計測機器による方法とが
ある。(Prior art) In order to determine whether or not the ground has liquefied during an earthquake, there are a method by visual inspection and a method by a measuring instrument using an earth pressure gauge and a pore water pressure gauge, as well as their amplifiers and recorders. is there.
（発明が解決しようとする課題） しかしながら目視調査による方法では、地表面におけ
る液状化判定は可能であるが、地盤内での判定はできな
い。(Problems to be Solved by the Invention) However, with the method by visual inspection, liquefaction determination on the ground surface is possible, but determination on the ground surface is not possible.
また土圧計と間隙水圧計を用いる計測機器による方法
では土圧力の測定自体が難しいこと、及び液状化の判定
をするには両者の値を比較しなければならないこと、更
に土圧計と間隙水圧計とが設置されている狭い範囲内で
の情報しか得られない。In addition, it is difficult to measure soil pressure itself with the method using a measuring instrument that uses an earth pressure gauge and a pore water pressure gauge, and it is necessary to compare the values of both in order to judge liquefaction. Information can only be obtained within the narrow range where and are installed.
このため地盤中の深奥に発生する微小破壊音を適確に
測定してAEの発生源を精度よく測定できるように、岩
石，土壌等の地盤に長孔を穿孔し、同孔内に流体を充填
するとともに、その内部に２個のAEセンサーを取り付け
て、地盤の内部に発生する微小破壊音の到達時間差を測
定してその発生源を標定するする方法が特開昭62−8368
5号公報において提案されている。For this reason, a long hole is drilled in the ground such as rocks and soil so that the sound of the source of AE can be measured accurately by accurately measuring the minute destructive sound generated deep inside the ground, and the fluid is introduced into the hole. JP-A-62-8368 discloses a method of filling and at the same time attaching two AE sensors to the inside of the ground to measure the arrival time difference of the minute destructive sound generated inside the ground and to locate the source thereof.
It is proposed in Japanese Patent Publication No. 5.
しかしながらこの地盤におけるAEの計測方法によれ
ば、トンネル等を掘削する場合、予め地山内部に発生し
た空洞，欠陥，割れ，硬軟等を適確に調査し、安全性，
施工法，工程，機材資材等を効率的に計画，実行するこ
とはできるが、将来地震時において発生が予測される地
盤の液状化現象に対応することは不可能であった。However, according to this AE measurement method in the ground, when excavating a tunnel or the like, it is necessary to properly investigate beforehand the cavities, defects, cracks, hardness, etc., that have occurred inside the ground, and
Although it is possible to efficiently plan and execute construction methods, processes, equipment materials, etc., it was impossible to deal with the liquefaction phenomenon of the ground, which is predicted to occur during future earthquakes.
本発明は前記従来技術の有する問題点に鑑みて提案さ
れたもので、その目的とするところは、簡単な構成で、
地盤の液状化が地盤のどの部分において発生したかを判
定し、この判定情報に基いて液状化の進行を未然に防止
する地盤の液状化防止装置を提供する点にある。The present invention has been proposed in view of the above problems of the prior art, and its object is to have a simple configuration.
An object of the present invention is to provide a ground liquefaction prevention device that determines in which part of the ground the liquefaction of the ground has occurred and that prevents the progress of the liquefaction based on this judgment information.
（課題を解決するための手段） 前記の目的を達成するため、本発明に係る地盤の液状
化防止装置は、液状化の可能性のある地盤内に設置さ
れ、且つ２個所にAEセンサーが配設された金属棒と、同
各AEセンサーに接続され同各AEセンサーによるAE信号を
検知するとともに、同各AE信号の到達時間差を計測する
AE処理装置と、同AE処理装置の計測データを入力して演
算処理するコンピュータと、前記液状化の可能性のある
地盤の周辺域に配置され、前記コンピュータによって地
盤の液状化が判定されると、同コンピュータの指令を受
けて作動する揚水装置より構成されている。(Means for Solving the Problem) In order to achieve the above-mentioned object, the ground liquefaction prevention device according to the present invention is installed in the ground where there is a possibility of liquefaction, and AE sensors are provided at two locations. It is connected to the installed metal rod and each AE sensor, detects the AE signal from each AE sensor, and measures the arrival time difference of each AE signal.
An AE processing device, a computer for inputting measurement data of the AE processing device and performing arithmetic processing, and is arranged in the peripheral area of the ground with the possibility of liquefaction, and the liquefaction of the ground is determined by the computer. , Is composed of a pumping device that operates in response to a command from the computer.
（作用） 地震時において、地盤に作用している土圧と、間隙水
圧とが等しくなった場合、土粒子はその土圧と水圧とが
バランスしているために浮いている状態、即ち液状化状
態となる。このとき、土粒子と水の動きが生起し、これ
に伴って音のエネルギが放出されるAE現象が発生する。(Operation) When the earth pressure acting on the ground becomes equal to the pore water pressure during an earthquake, the soil particles are in a floating state because the earth pressure and water pressure are balanced, that is, liquefaction. It becomes a state. At this time, the movement of soil particles and water occurs, which causes the AE phenomenon in which sound energy is released.
これに伴って前記したように地盤内に設置されたAE処
理装置における前記金属棒の２個所に配設されたAEセン
サーが前記したAE現象を検出し、同AE現象を検出したと
きの音の波形パラメータと、前記両センサのAE到達時間
差と、金属棒を伝わる音速とを計測することによって、
地盤内の液状化を判定することができる。Accordingly, as described above, the AE sensors arranged at two positions of the metal rod in the AE processing device installed in the ground detect the AE phenomenon described above, and the sound when the AE phenomenon is detected is detected. By measuring the waveform parameters, the AE arrival time difference of both sensors, and the speed of sound transmitted through the metal rod,
Liquefaction in the ground can be determined.
かくして地盤内の液状化を到達してAE処理装置の計測
データをコンピュータに入力して演算処理し、地盤の液
状化が判定されると前記液状化の可能性のある周辺域に
配設された揚水装置がコンピュータの指令を浮けて作動
し、地下水位の低下を図り、液状化の進行を阻止するも
のである。Thus, when the liquefaction in the ground is reached, the measurement data of the AE processing device is input to the computer and arithmetic processing is performed, and when the liquefaction of the ground is determined, it is arranged in the peripheral area where the liquefaction may occur. The pumping system operates by issuing a command from the computer to lower the groundwater level and prevent the progress of liquefaction.
（実施例） 以下、本発明を図示の実施例について説明する。
（Ａ）は護岸部（Ｂ）周辺における地下水位が高く、地
震時に液状化現象の生起する確率の高い砂質地盤で、同
砂質地盤（Ａ）に上下方向に間隔を存してAEセンサー
（１）が配設された、音を良好に伝達する金属棒（２）
（ウエーブガイド）が配設されている。(Examples) Hereinafter, the present invention will be described with reference to illustrated examples.
(A) is a sandy ground where the groundwater level around the revetment (B) is high and the liquefaction phenomenon is highly likely to occur during an earthquake. The AE sensor is located vertically above the sandy ground (A). A metal rod (2) provided with (1) and transmitting sound well.
(Wave guide) is provided.
前記各AEセンサー（１）は夫々ケーブル（３）を介し
てAE処理装置（４）に接続され、更に同AE処理装置
（４）はケーブル（３）を介してコンピュータ（５）に
接続されている。Each of the AE sensors (1) is connected to an AE processing device (4) via a cable (3), and the AE processing device (4) is connected to a computer (5) via a cable (3). There is.
更に前記地盤（Ａ）の周辺域に、前記コンピュータ
（５）の指令を浮けて作動する揚水装置（図示せず）が
配設されている。Further, in the peripheral area of the ground (A), a pumping device (not shown) that operates by floating the command of the computer (5) is arranged.
而して地震時において前記地盤（Ａ）が液状化し、土
粒子と水の動きが生じてAE現象が生起すると、前記AEセ
ンサー（１）によってこれを検出し、同AEセンサー
（１）による検出信号をAE信号かノイズかを判別して、
AE信号のみを取出してAE処理装置（４）に入力し、同AE
処理装置によって前記両AEセンサー（１）からのAE信号
到達時間差や、金属棒（２）を伝わる音速、AE信号を検
出したときの音の波形パラメーターを計測し、前記AE処
理装置（４）の計測データをコンピュータ（５）に入
力、演算し、地盤（Ａ）の液状化を判定する。When the ground (A) is liquefied during the earthquake and the movement of soil particles and water occurs to cause the AE phenomenon, the AE sensor (1) detects the AE phenomenon, and the AE sensor (1) detects the AE phenomenon. Determine whether the signal is AE signal or noise,
Only the AE signal is extracted and input to the AE processor (4),
The processing device measures the difference in the arrival time of the AE signals from the AE sensors (1), the speed of sound transmitted through the metal rod (2), and the waveform parameters of the sound when the AE signal is detected. The measurement data is input to the computer (5) and calculated to determine the liquefaction of the ground (A).
而して前記AEセンサー（１）は土粒子と水との微小な
動きによる音を検出することができるので、地盤（Ａ）
の液状化の初期段階を的確に捕えることができる。Thus, the AE sensor (1) can detect sound caused by minute movements of soil particles and water,
The initial stage of liquefaction of can be accurately captured.
かくして前記地盤（Ａ）の液状化が判定されると、同
地盤（Ａ）の周辺域に配置された揚水設備に前記コンピ
ュータ（５）により指令を発して同揚水設備を作動せし
め、地下水位の低下を図り、液状化の進行を早期に食い
止め、液状化を防止する。Thus, when the liquefaction of the ground (A) is determined, the computer (5) issues a command to the pumping equipment arranged in the peripheral area of the ground (A) to operate the pumping equipment, and Aim to lower the liquefaction and prevent the progress of liquefaction at an early stage to prevent liquefaction.
（発明の効果） 本発明に係る地盤の液状化防止装置によれば、地盤内
に設置され、且つ２個所にAEセンサーが配設された金属
棒と、同各AEセンサーに接続され、同各AEセンサーによ
るAE信号を検知するとともに、同AE信号の到達時間差を
計測するAE処理装置と、同AE処理装置の計測データを入
力して演算処理するコンピュータとによって、前記地盤
の液状化を判定し、同コンピュータからの指令によって
液状化の可能性のある地盤内に設置された揚水装置を作
動して、地下水位を低下せしめ、地盤の液状化の進行を
早期に食い止め、同地盤の液状化を防止するものであ
る。(Effects of the Invention) According to the ground liquefaction prevention device of the present invention, a metal rod installed in the ground and provided with two AE sensors, and connected to the respective AE sensors. Along with the AE signal detected by the AE sensor, the AE processing device that measures the arrival time difference of the AE signal and the computer that inputs the measurement data of the AE processing device and performs arithmetic processing to determine the liquefaction of the ground. In response to a command from the computer, the pumping device installed in the ground that may be liquefied is activated to lower the groundwater level, prevent the progress of liquefaction of the ground early, and liquefy the ground. To prevent.
第１図は本発明に係る地盤の液状化防止装置の一実施例
の実施状況を示す概略図である。 （Ａ）……砂質地盤、（１）……AEセンサー、（２）…
…金属棒、（４）……AE処理装置、（５）……コンピュ
ータ。FIG. 1 is a schematic view showing an implementation situation of an embodiment of a ground liquefaction prevention device according to the present invention. (A) …… Sandy ground, (1) …… AE sensor, (2)…
… Metal rod, (4) …… AE processor, (5) …… Computer.
Claims (1)
且つ２個所にAEセンサーが配設された金属棒と、同各AE
センサーに接続され同各AEセンサーによるAE信号を検知
するとともに、同各AE信号の到達時間差を計測するAE処
理装置と、同AE処理装置の計測データを入力して演算処
理するコンピュータと、前記液状化の可能性のある地盤
の周辺域に配置され、前記コンピュータによって地盤の
液状化が判定されると、同コンピュータの指令を受けて
作動する揚水装置とよりなることを特徴とする地盤の液
状化防止装置。1. It is installed in the ground where liquefaction is possible,
And the metal rods with AE sensors installed in two places and the same AE
An AE processing device that is connected to the sensor to detect the AE signal from each AE sensor and that measures the arrival time difference of each AE signal, and a computer that inputs the measurement data of the AE processing device and performs arithmetic processing, the liquid Liquefaction of the ground, which is arranged in a peripheral area of the ground that is likely to be liquefied, and which comprises a pumping device which operates when a liquefaction of the ground is judged by the computer. Prevention device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2144451A JP2543778B2 (en) | 1990-06-04 | 1990-06-04 | Ground liquefaction prevention device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2144451A JP2543778B2 (en) | 1990-06-04 | 1990-06-04 | Ground liquefaction prevention device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0438465A JPH0438465A (en) | 1992-02-07 |
| JP2543778B2 true JP2543778B2 (en) | 1996-10-16 |
Family
ID=15362547
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2144451A Expired - Fee Related JP2543778B2 (en) | 1990-06-04 | 1990-06-04 | Ground liquefaction prevention device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2543778B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2014162353A1 (en) * | 2013-04-02 | 2014-10-09 | 報国エンジニアリング株式会社 | Material sampling device and method for assessing liquefaction |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6283685A (en) * | 1985-10-09 | 1987-04-17 | Tokyu Constr Co Ltd | Method for measuring ae in ground |
-
1990
- 1990-06-04 JP JP2144451A patent/JP2543778B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0438465A (en) | 1992-02-07 |
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