JP2000046510A - Method and system for measuring improved body - Google Patents

Method and system for measuring improved body

Info

Publication number
JP2000046510A
JP2000046510A JP21224798A JP21224798A JP2000046510A JP 2000046510 A JP2000046510 A JP 2000046510A JP 21224798 A JP21224798 A JP 21224798A JP 21224798 A JP21224798 A JP 21224798A JP 2000046510 A JP2000046510 A JP 2000046510A
Authority
JP
Japan
Prior art keywords
measured
current
electrodes
improved body
potential
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.)
Withdrawn
Application number
JP21224798A
Other languages
Japanese (ja)
Inventor
Tadashi Ninomiya
正 二宮
Tetsuji Yasuoka
哲治 保岡
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Obayashi Corp
Original Assignee
Obayashi Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Obayashi Corp filed Critical Obayashi Corp
Priority to JP21224798A priority Critical patent/JP2000046510A/en
Publication of JP2000046510A publication Critical patent/JP2000046510A/en
Withdrawn legal-status Critical Current

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Landscapes

  • Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
  • Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
  • Testing Or Calibration Of Command Recording Devices (AREA)
  • Measurement Of Resistance Or Impedance (AREA)
  • Geophysics And Detection Of Objects (AREA)

Abstract

PROBLEM TO BE SOLVED: To obtain a highly reliable data without requiring any test work by determining the resistance per unit length using a current between current electrodes and a voltage between potential electrodes under a state where an electrode fixing body are arranged in an improved body to be measured. SOLUTION: An improving body 11 is built in the ground 21 and inserted with an electrode fixing body 3. A pair of current electrodes 4a, 4b fixed to the electrode fixing body 3 are then conducted and a current I flowing between the current electrodes is measured. On the other hand, potential difference V between potential electrodes 4c, 4d fixed to the electrode fixing body 3 is measured. Subsequently, the resistance R per unit length is determined using the measured current I between the current electrodes and the potential difference V between the potential electrodes. Assuming the distance between potential electrodes 4c, 4d is d, R=V/(I.d) is satisfied. Progress of the improving body 11, e.g. diameter, is calculated with reference to the relation between the resistance per unit length and the progress of the improving body 11 using the resistivity of natural ground as a parameter.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、地盤内に造成され
た改良体の出来高を計測するシステム及びその計測方法
に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for measuring the volume of an improved body formed in the ground and a measuring method therefor.

【0002】[0002]

【従来の技術】地盤改良やトンネル先受け等を目的とし
て地盤内に改良体が造成されることがある。例えば、軟
弱な地盤を改良する地盤改良工法においては、噴射ノズ
ルを回転させながら所定の硬化剤を地盤内に高圧噴射す
ることによって地盤への硬化剤注入を行うとともに、そ
の噴射エネルギーで地山の切削並びに地山との混合攪拌
を行う高圧噴射攪拌工法が知られており、かかる工法に
よれば、軟弱地盤内にパイル状の改良体を造成すること
ができる。また、山岳トンネル工法においては、トンネ
ル掘削に先だってトンネル外周にアーチ状に地山改良体
を形成するトンネル先受け工法(フォアパイリング工
法)が知られており、かかる工法によれば、切羽前方地
山を補強することが可能となる。
2. Description of the Related Art In some cases, an improved body is formed in the ground for the purpose of improving the ground or receiving a tunnel. For example, in a ground improvement method for improving soft ground, a hardener is injected into the ground by injecting a predetermined hardening agent into the ground at a high pressure while rotating an injection nozzle. A high-pressure injection stirring method for performing cutting and mixing and stirring with the ground is known. According to such a method, a pile-shaped improved body can be formed in soft ground. Also, in the mountain tunnel construction method, a tunnel front receiving construction method (fore piling construction method) is known in which a ground improvement body is formed in an arch shape on the outer periphery of the tunnel prior to tunnel excavation. Can be reinforced.

【0003】ところで、地盤改良等を行った後、造成さ
れた改良体の出来高、すなわち大きさや径あるいは断面
積等が意図した通りのものになっているかどうかを確認
することは重要な事項であるが、その確認方法として
は、本工事に先だって試験工事を行い、該試験工事で造
成された改良体の出来高をその周囲を掘り返すことによ
って直接計測する方法を採用する方が一般的である。
[0003] By the way, it is important to confirm after the ground improvement or the like that the height of the formed improved body, that is, whether the size, diameter, cross-sectional area, or the like is as intended. However, as a confirmation method, it is common to adopt a method of performing a test work prior to the main work, and directly measuring the yield of the improved body created in the test work by excavating the surrounding area.

【0004】[0004]

【発明が解決しようとする課題】このような試験工事に
よる計測方法は、弾性波、超音波などを用いた計測方法
よりも計測データの信頼性が高いという長所を有する反
面、本工事とは別に試験工事を行わねばならないため、
工期やコストの面で不利になるという問題を生じてい
た。また、現場が狭くて試験工事ができない、試験工事
を行う場所と本工事を行う場所の地質構造が一致すると
は限らない等の問題も生じていた。
The measuring method by such a test construction has an advantage that the measurement data is more reliable than the measuring method using an elastic wave, an ultrasonic wave, or the like. Because we have to do some testing work,
There has been a problem that it is disadvantageous in terms of construction period and cost. In addition, there are also problems such as the fact that the test site cannot be performed due to the small size of the site, and that the geological structure of the place where the test work is performed and the site where the main work is performed do not always match.

【0005】本発明は、上述した事情を考慮してなされ
たもので、試験工事を行うことなく信頼性の高いデータ
を得ることが可能な改良体の計測システム及び計測方法
を提供することを目的とする。
The present invention has been made in consideration of the above circumstances, and has as its object to provide an improved measurement system and a measurement method capable of obtaining highly reliable data without performing test work. And

【0006】[0006]

【課題を解決するための手段】上記目的を達成するた
め、本発明に係る改良体の計測システムは請求項1に記
載したように、計測対象となる改良体内に配置される電
極取付体と、該電極取付体に取り付けられた一対の電流
電極と、該一対の電流電極に電気接続された電源と、前
記電極取付体に取り付けられた電位電極と、該電位電極
に電気接続された電圧計と、前記計測対象となる改良体
内に前記電極取付体が配置された状態で計測された前記
電流電極間の電流及び前記電位電極間の電位差を用いて
単位長さ当たりの抵抗を求める演算手段とを備え、該演
算手段を、さまざまな地山比抵抗をパラメータとして予
め作成された単位長さ当たりの抵抗と改良体の出来高と
の関係と前記計測対象となる改良体付近で計測された地
山比抵抗とを用いて該計測対象となる改良体の出来高を
算出するように構成したものである。
In order to achieve the above-mentioned object, an improved body measuring system according to the present invention comprises, as described in claim 1, an electrode mounting body arranged in an improved body to be measured; A pair of current electrodes attached to the electrode attachment body, a power supply electrically connected to the pair of current electrodes, a potential electrode attached to the electrode attachment body, and a voltmeter electrically connected to the potential electrode. Calculating means for obtaining a resistance per unit length using a current between the current electrodes and a potential difference between the potential electrodes measured in a state where the electrode mounting body is arranged in the improved body to be measured. The arithmetic means is provided with a relationship between the resistance per unit length prepared in advance with various ground resistivity values as parameters and the yield of the improved body, and the ground ratio measured near the improved body to be measured. With resistance It is obtained by configured to calculate the volume of the improved body to be measured.

【0007】また、本発明に係る改良体の計測方法は請
求項2に記載したように、計測対象となる改良体内に電
極取付体を配置し、該電極取付体に取り付けられた一対
の電流電極を介して通電を行って該電流電極間の電流を
計測するとともに前記電極取付体に取り付けられた電位
電極を用いて該電位電極間の電位差を計測し、前記電流
電極間の電流及び前記電位電極間の電位差を用いて単位
長さ当たりの抵抗を求める一方、前記計測対象となる改
良体付近の地山比抵抗を計測し、しかる後に、さまざま
な地山比抵抗をパラメータとして予め作成された単位長
さ当たりの抵抗と改良体の出来高との関係を用いて前記
単位長さ当たりの抵抗から前記計測対象となる改良体の
出来高を算出するものである。
According to a second aspect of the present invention, there is provided a method for measuring an improved body, wherein an electrode mounting body is disposed in the improved body to be measured, and a pair of current electrodes mounted on the electrode mounting body. And a potential difference between the potential electrodes is measured using a potential electrode attached to the electrode mounting body, and a current between the current electrodes and the potential electrode are measured. The resistance per unit length is determined using the potential difference between the two, while the ground resistivity near the improved body to be measured is measured, and thereafter, a unit created in advance using various ground resistivity as a parameter. The volume of the improved body to be measured is calculated from the resistance per unit length using the relationship between the resistance per length and the volume of the improved body.

【0008】本発明に係る改良体の計測システム及び計
測方法においては、まず、計測対象となる改良体内に電
極取付体を配置する。電極取付体をどのように配置する
かは任意であるが、例えば改良体が完全に固化しないう
ちに挿入する、改良体が固化してから挿入孔を穿孔し、
該挿入孔内に挿入するなどの方法が考えられる。
In the improved body measuring system and the measuring method according to the present invention, first, an electrode mounting body is arranged in the improved body to be measured. How to arrange the electrode mounting body is optional, for example, to insert before the improved body is completely solidified, perforate the insertion hole after the improved body is solidified,
A method such as insertion into the insertion hole is conceivable.

【0009】次に、電極取付体に取り付けられた一対の
電流電極を介して通電を行って該電流電極間の電流を計
測するとともに、電極取付体に取り付けられた電位電極
を用いて該電位電極間の電位差を計測する。
Next, current is applied through a pair of current electrodes attached to the electrode mounting body to measure a current between the current electrodes, and the potential electrode is attached to the electrode mounting body using the potential electrode. Measure the potential difference between them.

【0010】次に、計測された電流電極間の電流及び電
位電極間の電位差を用いて単位長さ当たりの抵抗を求め
る。
Next, the resistance per unit length is determined using the measured current between the current electrodes and the potential difference between the potential electrodes.

【0011】一方、上述の手順とは別に、計測対象とな
る改良体付近の地山比抵抗を計測しておく。かかる地山
比抵抗の計測にあたっては、改良体を造成後、その近傍
箇所を計測位置としてもよいし、改良体を造成する前に
その造成予定箇所を計測位置としてもよい。
On the other hand, apart from the above procedure, the ground resistivity near the improved body to be measured is measured. In the measurement of the ground resistivity, after the improved body is created, a portion near the improved body may be set as the measurement position, or, before the improved body is created, the planned portion may be set as the measurement position.

【0012】次に、さまざまな地山比抵抗をパラメータ
として予め作成された単位長さ当たりの抵抗と改良体の
出来高との関係を参照することによって、既に算出した
単位長さ当たりの抵抗から計測対象となる改良体の出来
高、すなわち断面積、大きさ、直径等を算出する。
Next, by referring to the relationship between the resistance per unit length prepared in advance using various ground resistivity as a parameter and the yield of the improved body, measurement is made from the resistance per unit length already calculated. Calculate the volume of the target improved body, that is, the cross-sectional area, size, diameter, and the like.

【0013】単位長さ当たりの抵抗と改良体の出来高と
の関係を予め作成するにあたっては、実験による方法と
解析による方法との2つが考えられる。前者において
は、さまざまな比抵抗を持つ地山にさまざまな大きさの
改良体を実際に造成し、その周囲を掘り返して改良体を
計測するとともに、そのときの単位長さ当たりの抵抗を
上述したと同様に求めるようにすればよい。また、後者
においては、例えば軸対象FEMモデルを作成し、かか
るモデルに対して地山の比抵抗をパラメータとして解析
を行うようにすればよい。
In preparing the relationship between the resistance per unit length and the yield of the improved body in advance, there are two methods, an experimental method and an analytical method. In the former, improved bodies of various sizes were actually created on the ground with various specific resistances, and the surroundings were dug up to measure the improved bodies, and the resistance per unit length at that time was described above. What is necessary is just to ask for like. In the latter case, for example, an axially symmetric FEM model may be created, and the model may be analyzed using the resistivity of the ground as a parameter.

【0014】[0014]

【発明の実施の形態】以下、本発明に係る改良体の計測
システム及び計測方法の実施の形態について、添付図面
を参照して説明する。なお、従来技術と実質的に同一の
部品等については同一の符号を付してその説明を省略す
る。
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a measurement system and a measurement method for an improved body according to the present invention will be described with reference to the accompanying drawings. It is to be noted that the same reference numerals are given to components and the like that are substantially the same as those in the conventional technology, and description thereof will be omitted.

【0015】図1は、本実施形態に係る改良体の計測シ
ステムの全体図である。同図でわかるように、本実施形
態に係る改良体の計測システム1は、計測対象となる改
良体内に配置される中空円筒状の電極取付体3と、該電
極取付体の材軸に沿ってその外面に取り付けられた環状
の電極41、42、43、・・・・4nと、該電極に切換器
5を介して電気接続された直流電源6及び電圧計7と、
これら各機器を制御する演算手段としての演算制御部8
とを備える。
FIG. 1 is an overall view of an improved measurement system according to this embodiment. As can be seen from the figure, a measurement system 1 for an improved body according to the present embodiment includes a hollow cylindrical electrode mounting body 3 disposed in an improved body to be measured and a material axis along the material axis of the electrode mounting body. An annular electrode 4 1 , 4 2 , 4 3 ,... 4 n attached to the outer surface thereof; a DC power supply 6 and a voltmeter 7 electrically connected to the electrode via a switch 5;
An arithmetic control unit 8 as arithmetic means for controlling each of these devices
And

【0016】電極取付体3は、例えば硬質塩化ビニル、
FRP、プレキャストコンクリート等の非導電性部材で
構成するのがよいが、電極41、42、43、・・・・4n
並びに周囲に形成される造成体との電気的非接触が確保
されるのであれば、導電体である鋼管等で構成してもか
まわない。
The electrode mounting body 3 is made of, for example, hard vinyl chloride,
FRP, although it is preferable to constitute a non-conductive member such as precast concrete, electrodes 4 1, 4 2, 4 3 , ···· 4 n
In addition, as long as electrical non-contact with the surrounding formed body is ensured, a conductive steel tube or the like may be used.

【0017】直流電源6は、直流電流を流すことができ
るようになっていればよいが、直流とみなせるほど長い
周期で電源の極性を切り替えて矩形波(交替直流)を出
力することができるものでもよい。
The DC power supply 6 is only required to be able to flow a DC current, but can output a rectangular wave (alternating DC) by switching the polarity of the power supply in a cycle long enough to be regarded as DC. May be.

【0018】切換器5は、演算制御部8の制御下におい
て、電極41、42、43、・・・・4nのうち、所望の2
つの電極を一対の電流電極4a、4bとして選択するとと
もに、残りの電極のうち、所望の電極、例えば、一対の
電流電極4a、4bの間に配列された2つの電極を電位電
極4c、4dとして選択できるようになっている。
The switching device 5, under control of the arithmetic and control unit 8, the electrode 4 1, 4 2, 4 3, of · · · · 4 n, the desired 2
One electrode is selected as a pair of current electrodes 4a and 4b, and of the remaining electrodes, a desired electrode, for example, two electrodes arranged between the pair of current electrodes 4a and 4b are set as potential electrodes 4c and 4d. You can choose.

【0019】演算制御部8は、かかる切換器5を制御し
て一対の電流電極4a、4bを直流電源6に、一対の電位
電極4c、4dを電圧計7にそれぞれ電気接続するととも
に、かかる状態で直流電源6を作動させて電流電極4
a、4b間に電圧を印加することにより、図2に示すよう
に電極取付体3の周囲に造成された改良体11に通電
し、かかる状態で計測された電流電極4a、4b間の電流
及び電位電極4c、4d間の電位差を用いて単位長さ当た
りの抵抗を求めるようになっている。演算制御部8は、
例えばパーソナルコンピュータで構成することが可能で
ある。なお、電流電極4a、4b間の電流は、例えば直流
電源6に内蔵された電流計(図示せず)で計測するよう
にすればよい。
The arithmetic and control unit 8 controls the switch 5 to electrically connect the pair of current electrodes 4a and 4b to the DC power source 6 and electrically connect the pair of potential electrodes 4c and 4d to the voltmeter 7, respectively. Activate the DC power source 6 with the current electrode 4
By applying a voltage between a and 4b, the improved body 11 formed around the electrode mounting body 3 is energized as shown in FIG. 2, and the current between the current electrodes 4a and 4b measured in this state and The resistance per unit length is obtained using the potential difference between the potential electrodes 4c and 4d. The arithmetic control unit 8
For example, it can be constituted by a personal computer. The current between the current electrodes 4a and 4b may be measured by, for example, an ammeter (not shown) built in the DC power supply 6.

【0020】また、演算制御部8は、さまざまな地山比
抵抗をパラメータとして予め作成された単位長さ当たり
の抵抗と改良体の出来高との関係、並びに計測対象とな
る改良体11付近で計測された地山比抵抗とを用いて該
改良体11の出来高を算出するようになっている。
Further, the arithmetic and control unit 8 measures the relationship between the resistance per unit length prepared in advance using various ground resistivity values as parameters and the volume of the improved body, and measures the vicinity of the improved body 11 to be measured. The volume of the improved body 11 is calculated using the obtained ground resistivity.

【0021】本実施形態に係る改良体の計測システム1
及び計測方法においては、まず、図3に示すように、地
盤21に改良体11を造成し、しかる後に該改良体内に
電極取付体3を挿入する。電極取付体3は、例えば改良
体11が完全に固化しないうちに挿入するようにすれば
よい。改良体11の造成工法については、高圧噴射工法
やアースオーガを用いた攪拌工法などが考えられるが、
ここではどの工法で造成するのかは問わない。
Measurement system 1 for improved body according to this embodiment
In the measurement method, first, as shown in FIG. 3, the improved body 11 is formed on the ground 21, and then the electrode mounting body 3 is inserted into the improved body. The electrode attachment 3 may be inserted before the improved body 11 is completely solidified, for example. As a construction method of the improved body 11, a high-pressure injection method or a stirring method using an earth auger can be considered.
Here, it does not matter which construction method is used.

【0022】次に、電極取付体3に取り付けられた一対
の電流電極4a、4bを介して通電を行って該電流電極
間の電流Iを計測するとともに、電極取付体3に取り付
けられた電位電極4c、4dを用いて該電位電極間の電
位差Vを計測する。
Next, a current is applied through a pair of current electrodes 4a and 4b attached to the electrode mounting body 3 to measure a current I between the current electrodes, and a potential electrode attached to the electrode mounting body 3 is measured. The potential difference V between the potential electrodes is measured using 4c and 4d.

【0023】次に、計測された電流電極間の電流I及び
電位電極間の電位差Vを用いて単位長さ当たりの抵抗R
を求める。すなわち、電位電極4c、4d間の距離をd
とすると、単位長さ当たりの抵抗Rは、R=V/(I・
d)となる。
Next, using the measured current I between the current electrodes and the potential difference V between the potential electrodes, a resistance R per unit length is calculated.
Ask for. That is, the distance between the potential electrodes 4c and 4d is d
Then, the resistance R per unit length is R = V / (I ·
d).

【0024】一方、上述の手順とは別に、計測対象とな
る改良体11付近の地山の比抵抗を計測しておく。地山
の比抵抗を計測するにあたっては、例えば改良体11を
造成する前にその造成予定箇所を計測位置としていわゆ
るウェンナー法を用いて計測すればよい。
On the other hand, apart from the above procedure, the resistivity of the ground near the improved body 11 to be measured is measured. In measuring the specific resistance of the ground, for example, before constructing the improved body 11, it may be measured by using a so-called Wenner method with a planned construction site as a measurement position.

【0025】次に、さまざまな地山比抵抗をパラメータ
として予め作成された単位長さ当たりの抵抗と改良体の
出来高との関係を参照することによって、既に算出した
単位長さ当たりの抵抗Rから計測対象となる改良体11
の出来高、例えばその直径をを算出する。
Next, by referring to the relationship between the resistance per unit length prepared in advance and the volume of the improved body using various ground resistivity values as parameters, the resistance R per unit length already calculated is referred to. Improved body 11 to be measured
, For example, its diameter is calculated.

【0026】単位長さ当たりの抵抗と改良体の出来高と
の関係については、例えば造成体を円筒体とするととも
に該造成体とその周囲に拡がる地山とを造成体の材軸を
中心とした軸対象FEMモデルとしてモデル化し、かか
るFEMモデルに対して地山の比抵抗をパラメータとし
た解析を行うことで得られる。なお、解析を行うにあた
り、造成体の比抵抗が入力データとして当然必要になる
が、軟弱地盤とモルタルとの攪拌混合なのか、モルタル
のみの充填注入なのかによって造成された改良体の比抵
抗にはそれなりの差が生じる。したがって、造成体の解
析上の比抵抗については、工法を考慮して適宜定めるよ
うにする。
With respect to the relationship between the resistance per unit length and the height of the improved body, for example, the formed body is made into a cylindrical body, and the formed body and the ground extending around the center are centered on the material axis of the formed body. It is obtained by modeling as an axially symmetric FEM model and performing an analysis on the FEM model using the resistivity of the ground as a parameter. In conducting the analysis, the specific resistance of the formed body is naturally required as input data.However, the specific resistance of the improved body formed depending on whether it is stirring mixing of soft ground and mortar, or filling and filling only mortar Causes a certain difference. Therefore, the analytical specific resistance of the formed body is appropriately determined in consideration of the construction method.

【0027】図4は、地山比抵抗が58Ω・m、300
Ω・m、及び無限大の3つのケースについて単位長さ当
たりの抵抗(Ω/m)と改良体の直径(cm)との関係
を上述した軸対象FEMモデルを用いて求めた解析結果
を示したグラフである。
FIG. 4 shows that the ground resistivity is 58 Ω · m, 300
The analysis results obtained by using the above-mentioned axial symmetric FEM model for the relationship between the resistance per unit length (Ω / m) and the diameter of the improved body (cm) for the three cases of Ω · m and infinity are shown. FIG.

【0028】かかるグラフを参照して改良体11の直径
を算出するには、例えば現場で計測された地山の比抵抗
が300Ω・m、単位長さ当たりの抵抗Rが24Ω/m
だとすると、改良体11の直径は、20cmであると算
出できる。
In order to calculate the diameter of the improved body 11 with reference to such a graph, for example, the resistivity of the ground measured at the site is 300 Ω · m, and the resistance R per unit length is 24 Ω / m.
Then, the diameter of the improved body 11 can be calculated to be 20 cm.

【0029】なお、図4に示したような解析結果は、例
えば図示しない記憶装置に参照テーブルのような形で記
憶しておき、必要なときに該記憶装置から演算制御部8
で読み出すとともに、現地で計測された単位長さ当たり
の抵抗Rが解析結果に存在しないときには、解析結果を
適宜補間するのがよい。
The analysis results as shown in FIG. 4 are stored in a storage device (not shown) in the form of a look-up table, for example.
When the resistance R per unit length measured in the field does not exist in the analysis result, it is preferable to appropriately interpolate the analysis result.

【0030】以上説明したように、本実施形態に係る改
良体の計測システム及び計測方法によれば、電流電極4
a、4b間の電流I及び電位電極4c、4d間の電位差
Vを用いて単位長さ当たりの抵抗Rを求める一方、計測
対象となる改良体11付近の地山比抵抗を計測し、しか
る後に、さまざまな地山比抵抗をパラメータとして予め
作成された単位長さ当たりの抵抗と改良体の出来高との
関係を用いて上述の単位長さ当たりの抵抗Rから改良体
11の出来高を算出するようにしたので、従来の弾性波
探査や超音波探査よりも高い精度で、しかも弾性波や超
音波の受発信装置を設置する手間をかけることなく、改
良体の出来高を効率よくしかも正確に計測することが可
能となる。
As described above, according to the improved measuring system and method of the present embodiment, the current electrode 4
While the resistance R per unit length is obtained using the current I between a and 4b and the potential difference V between the potential electrodes 4c and 4d, the ground resistivity near the improved body 11 to be measured is measured. The yield of the improved body 11 is calculated from the above-described resistance R per unit length using the relationship between the resistance per unit length and the yield of the improved body prepared in advance using various ground resistivity values as parameters. As a result, the volume of the improved body can be measured efficiently and accurately with higher accuracy than conventional elastic wave or ultrasonic surveys, and without the need to install an elastic wave or ultrasonic transmitter / receiver. It becomes possible.

【0031】また、従来のように本工事とは別途試験工
事を行う必要がなくなるので、地盤改良工事等の工期や
コストを大幅に低減することが可能となるとともに、言
うなれば供試体を対象としていたにすぎない試験工事と
は違い、あくまで本設の改良体の出来高を非破壊でしか
も硬化剤注入直後に計測することができるので、造成範
囲が当初の目標よりも小さいことが明らかになった場合
には硬化剤の再注入を行うといった対策を施すことも可
能となり、地盤改良工事等の施工品質を大幅に向上させ
ることができる。
In addition, since it is not necessary to carry out a test work separately from the main work as in the prior art, it is possible to greatly reduce the construction period and cost for ground improvement work and the like, and in other words, to test the test specimen. Unlike the test work, which was just a test work, it was clarified that the construction area was smaller than the original target because the volume of the improved body could be measured nondestructively and immediately after injection of the hardener. In such a case, it is also possible to take measures such as re-injecting the curing agent, and it is possible to greatly improve the construction quality of ground improvement work and the like.

【0032】また、本実施形態に係る改良体の計測シス
テムによれば、電極取付体3の外面にその材軸に沿って
電極41、42、43、・・・・4nを多数配列するととも
に該電極を切換器5を介して直流電源6及び電圧計7に
電気接続し、該切換器を、電極41、42、43、・・・
・4nのうち、所望の電極を一対の電流電極4a、4b及
び電位電極4c、4dとして任意に選択できるように構成
したので、地山の比抵抗や改良体の性状に適した電流電
極や電位電極の切換えを瞬時に行うことが可能となる。
According to the improved measuring system of the present embodiment, a large number of electrodes 4 1 , 4 2 , 4 3 ,..., 4 n are provided on the outer surface of the electrode mounting body 3 along the material axis. The electrodes are arranged and electrically connected to a DC power supply 6 and a voltmeter 7 via a switch 5, and the switches are connected to the electrodes 4 1 , 4 2 , 4 3 ,.
· 4 n of the desired electrode pair of current electrodes 4a, 4b and potential electrodes 4c, so constituted as can be selected arbitrarily as 4d, current electrode Ya suitable for the properties of the specific resistance and improvements of the natural ground Switching of the potential electrode can be performed instantaneously.

【0033】本実施形態では特に言及しなかったが、上
述した単位長さ当たりの抵抗を算出するための電流Iや
電位差Vの計測は、改良体11の硬化の進行具合とは無
関係に行うことが可能であり、現場で計測されるときの
改良体11の比抵抗と解析に用いた改良体の比抵抗とが
対応さえしておれば足りる。
Although not specifically mentioned in the present embodiment, the measurement of the current I and the potential difference V for calculating the resistance per unit length described above is performed irrespective of the progress of the hardening of the improved body 11. It is sufficient that the specific resistance of the improved body 11 measured at the site and the specific resistance of the improved body used in the analysis correspond to each other.

【0034】また、本実施形態では、本発明を地盤改良
工法に適用した例で説明したが、本発明は、地盤内に改
良体が造成されるすべての場合に適用することが可能で
ある。例えば、地下構造物の防護工、地盤強化、トンネ
ルの先受け工等にも適用することが可能であるし、図5
に示すように、トンネル掘削において切羽31前方に空
洞32の存在が確認された場合、掘削に伴う土砂の崩壊
を防止すべく、該空洞に予めグラウト33の注入を行う
ことがあるが、かかるグラウト33の造成範囲を計測す
る際にも本発明を適用することができる。
Further, in the present embodiment, an example in which the present invention is applied to a ground improvement method has been described. However, the present invention can be applied to all cases where an improved body is formed in the ground. For example, the present invention can be applied to protection work for underground structures, ground reinforcement, tunnel precedent work, and the like.
As shown in the figure, when the presence of the cavity 32 is confirmed in front of the face 31 in tunnel excavation, grout 33 may be injected into the cavity in advance in order to prevent collapse of earth and sand due to excavation. The present invention can also be applied when measuring the creation range of 33.

【0035】すなわち、同図に示すように、グラウト機
36には、本実施形態と同様の切換器5、直流電源6、
電圧計7及び演算制御部8を内蔵した制御装置37を設
置してあり、直流電源6及び電圧計7は、本実施形態と
同様、切換器5を介して電極取付体35に取り付けた電
極41、42、43、・・・・4nに電気接続してある。
That is, as shown in the figure, a grouting machine 36 includes a switch 5, a DC power supply 6,
A control device 37 having a built-in voltmeter 7 and an arithmetic control unit 8 is installed. The DC power supply 6 and the voltmeter 7 are connected to the electrode 4 attached to the electrode mounting body 35 via the switch 5 as in the present embodiment. 1 , 4 2 , 4 3 ,..., 4 n are electrically connected.

【0036】計測を行うにあたっては、まず、グラウト
33内に電極取付体35を挿入し、しかる後に本実施形
態と同様の手順で単位長さ当たりの抵抗Rを算出してグ
ラウト33の出来高を計測すればよい。なお、本変形例
では、電極取付体35は、グラウト注入管としての機能
を兼ね備えたものである。
In performing the measurement, first, the electrode mounting body 35 is inserted into the grout 33, and thereafter, the resistance R per unit length is calculated by the same procedure as in the present embodiment to measure the volume of the grout 33. do it. In this modification, the electrode mounting body 35 also has a function as a grout injection pipe.

【0037】また、本実施形態では、地山の比抵抗の違
いや工法の違いにも対応できるように、切換器5を設け
て電流電極及び電位電極の位置や間隔を変更できるよう
にしたが、基本的には、電流電極及び電位電極はそれぞ
れ一対あれば足り、切換器5も不要である。
In this embodiment, the switch 5 is provided so that the positions and intervals of the current electrode and the potential electrode can be changed so as to cope with the difference in the specific resistance of the ground and the difference in the construction method. Basically, only one pair of the current electrode and the potential electrode is required, and the switch 5 is unnecessary.

【0038】また、本実施形態では、電極取付体3を中
空円筒状とし、該中空空間内に計測ケーブルを通すよう
にしたが、これに代えて電極取付体を棒状体とし、その
棒状体の周面に沿って計測ケーブルを配置するようにし
てもよいことは言うまでもない。
Further, in the present embodiment, the electrode mounting body 3 is formed in a hollow cylindrical shape, and the measurement cable is passed through the hollow space. It goes without saying that the measurement cable may be arranged along the peripheral surface.

【0039】[0039]

【発明の効果】以上述べたように、請求項1の発明に係
る改良体の計測システム及び請求項2の発明に係る改良
体の計測方法によれば、従来の弾性波探査や超音波探査
よりも高い精度で、しかも弾性波や超音波の受発信装置
を設置する手間をかけることなく、改良体の出来高を効
率よくしかも正確に計測することが可能となる。また、
従来のように本工事とは別途試験工事を行う必要がなく
なるので、地盤改良工事等の工期やコストを大幅に低減
することが可能となる。
As described above, according to the improved body measuring system according to the first aspect of the present invention and the improved body measuring method according to the second aspect of the present invention, the conventional elastic wave exploration and ultrasonic exploration can be performed. It is also possible to measure the output of the improved body efficiently and accurately with high accuracy and without having to install a transmitting / receiving device for elastic waves or ultrasonic waves. Also,
Since it is no longer necessary to perform test work separately from the main work as in the prior art, it is possible to greatly reduce the construction period and cost of ground improvement work and the like.

【0040】[0040]

【図面の簡単な説明】[Brief description of the drawings]

【図1】本実施形態に係る改良体の計測システムの全体
図。
FIG. 1 is an overall view of a measurement system for an improved body according to an embodiment.

【図2】本実施形態に係る改良体の計測システムの作用
を示した断面図。
FIG. 2 is a sectional view showing the operation of the improved measurement system according to the embodiment;

【図3】本実施形態に係る改良体の計測方法にしたが
い、造成された改良体に電極取付体を挿入した様子を示
した断面図。
FIG. 3 is a cross-sectional view showing a state where an electrode mounting body is inserted into the formed improved body according to the improved body measuring method according to the embodiment.

【図4】地山比抵抗が58Ω・m、300Ω・m、及び
無限大の3つのケースについて単位長さ当たりの抵抗
(Ω/m)と改良体の直径(cm)との関係を上述した
軸対象FEMモデルを用いて求めた解析結果を示したグ
ラフ。
FIG. 4 shows the relationship between the resistance per unit length (Ω / m) and the diameter (cm) of the improved body in three cases where the ground resistivity is 58 Ω · m, 300 Ω · m, and infinity. 7 is a graph showing an analysis result obtained by using an axially symmetric FEM model.

【図5】本実施形態に係る改良体の計測システムをトン
ネルグラウトに適用した例を示した全体図。
FIG. 5 is an overall view showing an example in which the improved measurement system according to the present embodiment is applied to a tunnel grout.

【符号の説明】[Explanation of symbols]

1 改良体の計測システム 3 電極取付体 41、42、43、・・・・4n電極 4a、4b 電流電極 4c、4d 電位電極 5 切換器 6 直流電源(電源) 7 電圧計 8 演算制御部(演算手段) 11 改良体DESCRIPTION OF SYMBOLS 1 Measurement system of improved body 3 Electrode mounting body 4 1 , 4 2 , 4 3 ,... 4 n electrode 4 a, 4 b Current electrode 4 c, 4 d Potential electrode 5 Switch 6 DC power supply (power supply) 7 Voltmeter 8 Calculation Control unit (computing means) 11 Improved body

───────────────────────────────────────────────────── フロントページの続き Fターム(参考) 2D040 AB01 AB03 BB03 BB09 BD05 CB03 GA02 2F063 AA11 AA50 BB10 CA40 EA20 EB21 FA09 FA10 FA16 LA09 LA23 LA25 2F076 BB07 BD02 BE04 BE05 BE19 2G028 AA01 BC06 CG02 DH03 FK01 HM05 HN02 HN07 HN12 HN13 ──────────────────────────────────────────────────続 き Continuing on the front page F term (reference) 2D040 AB01 AB03 BB03 BB09 BD05 CB03 GA02 2F063 AA11 AA50 BB10 CA40 EA20 EB21 FA09 FA10 FA16 LA09 LA23 LA25 2F076 BB07 BD02 BE04 BE05 BE19 2G028 AA01 BC06 CG02 DH03 H01N02N

Claims (2)

【特許請求の範囲】[Claims] 【請求項1】 計測対象となる改良体内に配置される電
極取付体と、該電極取付体に取り付けられた一対の電流
電極と、該一対の電流電極に電気接続された電源と、前
記電極取付体に取り付けられた電位電極と、該電位電極
に電気接続された電圧計と、前記計測対象となる改良体
内に前記電極取付体が配置された状態で計測された前記
電流電極間の電流及び前記電位電極間の電位差を用いて
単位長さ当たりの抵抗を求める演算手段とを備え、該演
算手段を、さまざまな地山比抵抗をパラメータとして予
め作成された単位長さ当たりの抵抗と改良体の出来高と
の関係と前記計測対象となる改良体付近で計測された地
山比抵抗とを用いて該計測対象となる改良体の出来高を
算出するように構成したことを特徴とする改良体の計測
システム。
1. An electrode mounting body disposed in an improved body to be measured, a pair of current electrodes mounted on the electrode mounting body, a power supply electrically connected to the pair of current electrodes, and the electrode mounting A potential electrode attached to the body, a voltmeter electrically connected to the potential electrode, a current between the current electrodes measured in a state where the electrode attachment body is arranged in the improved body to be measured, and Calculating means for calculating the resistance per unit length using the potential difference between the potential electrodes, the calculating means comprising: a resistance per unit length prepared in advance using various ground resistivity values as parameters; Measurement of the improved body characterized in that it is configured to calculate the volume of the improved body to be measured using the relationship with the volume and the ground resistivity measured near the improved body to be measured. system.
【請求項2】 計測対象となる改良体内に電極取付体を
配置し、該電極取付体に取り付けられた一対の電流電極
を介して通電を行って該電流電極間の電流を計測すると
ともに前記電極取付体に取り付けられた電位電極を用い
て該電位電極間の電位差を計測し、前記電流電極間の電
流及び前記電位電極間の電位差を用いて単位長さ当たり
の抵抗を求める一方、前記計測対象となる改良体付近の
地山比抵抗を計測し、しかる後に、さまざまな地山比抵
抗をパラメータとして予め作成された単位長さ当たりの
抵抗と改良体の出来高との関係を用いて前記単位長さ当
たりの抵抗から前記計測対象となる改良体の出来高を算
出することを特徴とする改良体の計測方法。
2. An electrode mounting body is arranged in an improved body to be measured, and a current is applied between the current electrodes through a pair of current electrodes mounted on the electrode mounting body to measure a current between the current electrodes. The potential difference between the potential electrodes is measured using a potential electrode attached to the mounting body, and the resistance per unit length is determined using the current between the current electrodes and the potential difference between the potential electrodes, while the measurement target Measure the resistivity of the ground near the improved body, and thereafter, the unit length using the relationship between the resistance per unit length and the volume of the improved body prepared in advance using various ground resistivity as parameters A method of measuring an improved body, comprising calculating a volume of the improved body to be measured from a contact resistance.
JP21224798A 1998-07-28 1998-07-28 Method and system for measuring improved body Withdrawn JP2000046510A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP21224798A JP2000046510A (en) 1998-07-28 1998-07-28 Method and system for measuring improved body

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP21224798A JP2000046510A (en) 1998-07-28 1998-07-28 Method and system for measuring improved body

Publications (1)

Publication Number Publication Date
JP2000046510A true JP2000046510A (en) 2000-02-18

Family

ID=16619421

Family Applications (1)

Application Number Title Priority Date Filing Date
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Country Status (1)

Country Link
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102645155A (en) * 2011-02-18 2012-08-22 韩国地质资源研究院 Method for detecting structural stability of object area and apparatus for the same
JP2013227724A (en) * 2012-04-24 2013-11-07 System Keisoku Kk Strength management method for cement-based improvement body
JP2016125870A (en) * 2014-12-26 2016-07-11 東日本旅客鉄道株式会社 Conduction state determination method and measuring apparatus
JP2018072052A (en) * 2016-10-26 2018-05-10 株式会社クボタ Specific resistance measuring apparatus of soil
KR20230067499A (en) * 2021-11-08 2023-05-16 (주)지오룩스 Complex underground sensor and method for monitoring underground contamination using the same for minimizing soil disturbing

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102645155A (en) * 2011-02-18 2012-08-22 韩国地质资源研究院 Method for detecting structural stability of object area and apparatus for the same
JP2013227724A (en) * 2012-04-24 2013-11-07 System Keisoku Kk Strength management method for cement-based improvement body
JP2016125870A (en) * 2014-12-26 2016-07-11 東日本旅客鉄道株式会社 Conduction state determination method and measuring apparatus
JP2018072052A (en) * 2016-10-26 2018-05-10 株式会社クボタ Specific resistance measuring apparatus of soil
KR20230067499A (en) * 2021-11-08 2023-05-16 (주)지오룩스 Complex underground sensor and method for monitoring underground contamination using the same for minimizing soil disturbing
KR102565165B1 (en) * 2021-11-08 2023-08-09 (주)지오룩스 Complex underground sensor and method for monitoring underground contamination using the same for minimizing soil disturbing

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