KR20140025104A - Apparatus for measurement of ground and method for measuring ground using the same - Google Patents

Apparatus for measurement of ground and method for measuring ground using the same Download PDF

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Publication number
KR20140025104A
KR20140025104A KR1020120091301A KR20120091301A KR20140025104A KR 20140025104 A KR20140025104 A KR 20140025104A KR 1020120091301 A KR1020120091301 A KR 1020120091301A KR 20120091301 A KR20120091301 A KR 20120091301A KR 20140025104 A KR20140025104 A KR 20140025104A
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KR
South Korea
Prior art keywords
ground
measuring
displacement
fixing member
measuring unit
Prior art date
Application number
KR1020120091301A
Other languages
Korean (ko)
Inventor
유진오
손성곤
강성현
Original Assignee
코오롱글로벌 주식회사
주식회사 티에스테크노
아진엔지니어링 주식회사
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Application filed by 코오롱글로벌 주식회사, 주식회사 티에스테크노, 아진엔지니어링 주식회사 filed Critical 코오롱글로벌 주식회사
Priority to KR1020120091301A priority Critical patent/KR20140025104A/en
Publication of KR20140025104A publication Critical patent/KR20140025104A/en

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    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D1/00—Investigation of foundation soil in situ
    • E02D1/02—Investigation of foundation soil in situ before construction work
    • E02D1/022—Investigation of foundation soil in situ before construction work by investigating mechanical properties of the soil
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D2300/00—Materials
    • E02D2300/0004—Synthetics
    • E02D2300/0018—Cement used as binder
    • E02D2300/0021—Mortar
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D2600/00—Miscellaneous
    • E02D2600/10—Miscellaneous comprising sensor means

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  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Mining & Mineral Resources (AREA)
  • Soil Sciences (AREA)
  • Analytical Chemistry (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Paleontology (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)
  • Force Measurement Appropriate To Specific Purposes (AREA)

Abstract

The present invention relates to a ground measuring apparatus used to measure ground displacement comprising: a fixing member (100) fixed in a bored hole (1) formed on the ground; a connection member (200) inserted into the bored hole (1) and coupled to the outside of the fixing member (100); a ground measuring unit (300) installed in the outer edge of the bored hole (1) and in the front of connecting member (200) in order to measure the ground displacement generated in a installation area of the connecting member (200) or the change of the axial force of the fixing member (100) caused by the ground displacement. The ground measuring apparatus can predict the collapse of ground by precisely measuring the relaxation area of the ground and ensure stability by responding to the ground displacement.

Description

Ground measuring apparatus and ground measuring method using same {APPARATUS FOR MEASUREMENT OF GROUND AND METHOD FOR MEASURING GROUND USING THE SAME}

The present invention relates to the field of civil engineering, and more particularly, to a ground measuring apparatus and a ground measuring method using the same.

When excavating the ground to install the structure when the ground excavation, there is a fear that the ground is collapsed or the stability of the structure is degraded due to the loosening action of the ground.

In order to predict such a situation in advance, a technique of measuring a relaxation area of the ground by inserting a ground measuring apparatus in the ground is used.

In the conventional ground measuring apparatus 10, a structure in which a plurality of sensors 12 are provided in the main body 11 is mainly used (FIG. 1).

However, the ground measuring apparatus of such a structure has the following problems.

First, the precision is low.

When grouting after inserting the conventional ground measuring apparatus 10 into the drilling hole 1, the main body 11 and the sensor 12 are integrated, so that the same value may be measured in all of the plurality of sensors 12. There is.

Therefore, there is a problem in that the precision is low because it is impossible to accurately grasp the loose region of the ground.

Second, workability is low.

The conventional ground measuring apparatus 10 has a disadvantage in that measurement is impossible for a time until the filling of mortar and resin is cured after being inserted into the drilling hole 1.

Therefore, it takes a lot of time to measure the displacement of the ground by using the conventional ground measuring apparatus 10 has a problem that workability is very low.

The present invention was derived to solve the above problems, the ground measuring device that can accurately measure the relaxation area of the ground to predict the collapse of the ground in advance, and ensure the stability in response to the displacement of the ground and the same It is an object of the present invention to provide a method for measuring ground use.

In order to solve the above problems, the present invention is a ground measuring apparatus used to measure the displacement of the ground, the fixing member 100 is fixed to the inside of the drilling hole (1) formed in the ground; A connection member 200 inserted into the drilling hole 1 and coupled to the outside of the fixing member 100; On the outer edge of the drilling hole 1 and the front end of the connecting member 200 to measure the displacement of the ground occurring in the connection member 200 installation area or the change in the axial force of the fixing member 100 due to this It presents a ground measuring apparatus comprising a; ground measuring unit 300 installed.

The fixing member 100 is formed to have a hollow in which the pressure fluid 100A is injected and drained, and the fixing member 100 is fixed through the hollow of the connecting member 200 in a state in which a portion is pressed in a concave shape along the circumferential direction thereof. It is preferably expanded by the pressure fluid 100A supplied to the hollow of the member 100 and made of a steel pipe.

The ground measuring unit 300 preferably includes a ground displacement measuring unit 310 for measuring the displacement of the ground.

The ground displacement measuring unit 310 includes a displacement sensor (LVDT) 311 for measuring a change in relative distance from the front end of the connecting member 200 exposed through the trim of the drilling hole 1; And a fixing part 312 for fixing the displacement sensor (LVDT) 311 to the edge of the drilling hole 1.

The ground displacement measuring unit 310 may further include a pressure plate 313 installed at an outer edge of the drilling hole 1 to support the fixing part 312.

The ground measuring unit 300 preferably includes an axial force measuring unit 320 for measuring a change in the axial force of the fixing member 100.

The axial force measuring unit 320 includes an axial force meter 321 installed to be fixed to an edge of the drilling hole 1 around the outer circumference of the connection member 200; It is preferable to include a; cap 322 installed in the front end of the connecting member 200, so that the stress generated in the connecting member 200 is transmitted to the axial system 321.

The axial force measuring unit 320 may further include a pressure plate 313 installed at an outer edge of the drilling hole 1 to support the axial force meter 321.

The present invention is a ground measuring structure using the ground measuring device, wherein the plurality of ground measuring devices are respectively installed in the plurality of drilling holes (1), and the plurality of fixing members (100) are disposed at different depths, respectively. In addition, the connection member 200 presents a ground measurement structure using a ground measuring device, characterized in that disposed in the relaxation area of the ground different from each other.

The present invention is a ground measuring method using the ground measuring structure, the drilling step of forming the plurality of drilling holes (1) in the ground; Installing the ground measuring device in the drilling hole (1), the fixing member for each depth installation step for placing the fixing member 100 at different depths; A ground measuring unit installing step of installing the ground measuring unit 300 at an outer edge of the drilling hole 1 and the front end of the connecting member 200; A ground displacement measuring step of measuring ground displacement using the ground measuring unit 300 or a change in the axial force of the fixing member 100 due to the ground displacement; present.

A ground measuring method using the ground measuring structure, the drilling step of forming the plurality of drilling holes (1) in the shotcrete layer (2) and the back ground (3) of the tunnel; Installing the ground measuring device in the drilling hole (1), the fixing member for each depth installation step for placing the fixing member 100 at different depths; A ground measuring unit installing step of installing the ground measuring unit 300 at a front end of the connection member 200 formed on the surface of the shotcrete layer 2; It is preferable to include; a ground displacement measuring step of measuring the displacement of the ground using the ground measuring unit 300 or a change in the axial force of the fixing member 100 due to this.

The present invention provides a ground measuring apparatus and a ground measuring method using the same, which accurately predicts the ground loosening area and accurately predicts the ground collapse, thereby ensuring stability in response to the ground displacement.

1 is a conventional ground measuring apparatus.
2 to 5 show an embodiment of the ground measuring apparatus according to the present invention,
2 is a sectional view of the first embodiment;
3 is a cross-sectional view of the fixing member.
4 is a sectional view of the use of the fixing member.
5 is a sectional view of the second embodiment;
6 is a cross-sectional view of a ground measuring structure using a ground measuring device.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in Figure 2 below, the ground measuring apparatus proposed in the present invention is a fixing member 100 fixed to the inside of the drilling hole (1) formed in the ground; A connection member 200 inserted into the drilling hole 1 and coupled to the outside of the fixing member 100; Ground measurement installed on the outer edge of the drilling hole 1 and the front end of the connecting member 200 to measure the displacement of the ground occurring in the connection member 200 installation area or the change in the axial force of the fixing member 100 due to this. The unit 300 is characterized by a structure including a (FIG. 2).

The ground measuring apparatus 10 used conventionally is a structure in which the several sensor 12 was provided in the main body 11 (FIG. 1).

The ground measuring device 10 is installed in the drilling hole 1, and ground measurement is performed after grouting.

However, the conventional ground measuring apparatus 10 has a problem in that the main body 11 and the plurality of sensors 12 are integrated due to the grouting operation so that the same values are measured in the plurality of sensors 12.

Therefore, it is impossible to accurately grasp the relaxation region of the ground.

On the other hand, in the ground measuring apparatus proposed in the present invention, rather than installing a plurality of sensors in one ground measuring apparatus, a plurality of fixing members 100 by using the connection member 200 of different lengths are drilled holes (1). ) To be used at different depths () (FIG. 6).

With such a configuration, it is possible to estimate whether or not the ground (a1) of the ground corresponding to the installation region of the connecting member 200.

By the way, the present invention has a feature that the installation area of the connecting member 200 is formed in various ways because it is installed by varying the installation depth of the fixing member 100 (Fig. 6).

Therefore, the effect that estimation of the loosening areas a1, a2, a3, a4 of different grounds is possible.

Through this, by appropriately preparing for the displacement of the ground, it is possible to ensure the stability of the structure to be installed.

The ground measuring device does not require a separate grouting operation because the fixing member 100 is completely attached to the ground after the fixing member 100 is installed inside the drilling hole 1.

Therefore, there is no fear that problems caused by the grouting operation occur in the prior art, and the effect of improving workability is obtained.

Here, the structure for fixing the fixing member 100 to the inside of the drilling hole 1 will be described in detail.

The fixing member 100 made of a steel pipe is formed to have a hollow in which the pressure fluid 100A is injected and drained, and is inserted into the drilling hole 1 in a state in which a portion is pressed in a recessed shape along its circumferential direction (FIG. 3).

After being inserted into the drilling hole 1, when the pressure fluid 100A is supplied through the hollow of the connecting member 200, the fixing member 100 is expanded by the pressure fluid 100A to completely adhere to the ground. (FIG. 4).

As the fixing member 100 is fixed in close contact with the ground, the binding force between the ground measuring device and the ground is increased.

That is, the fixing member 100 serves to reinforce the rock by fixing the rock softened by blasting, etc. to a solid and stable rock, preventing the ground from collapsing.

In addition, the conventional ground measuring apparatus 10 is installed in the drilling hole (1), it takes a lot of time to harden the filler, such as mortar and resin, there is a problem that the ground measurement is impossible during that time.

On the other hand, in the ground measuring device of the present invention, since the fixing member 100 is completely attached to the ground within a short time after the drilling hole 1 is installed, the time required to measure by using the ground measuring unit 300 after installation This is very short.

Therefore, the ground measuring device has an advantage that the workability is very excellent because it can measure the displacement of the ground or the change of axial force caused by the ground within a short time, and thereby determine the stability of the ground.

Ground measurement unit 300 for measuring the displacement of the ground generated in the connection member 200 installation area or the resulting axial force change may be used in the following structure.

First, the ground displacement measuring unit 310 may be used as the ground measuring unit 300 to measure the displacement of the ground caused by the loosening action of the ground.

The ground displacement measuring unit 310 is a displacement sensor (LVDT) 311 for measuring a change in the relative distance with the front end of the connecting member 200 exposed through the opening of the drilling hole (1); and the displacement sensor (LVDT) ( It is formed in a structure including; a fixing portion 312 for fixing the 311 to the edge of the drilling hole (1).

That is, when the ground is relaxed, the connecting member 200 is relatively far from the displacement sensor LVDT 311.

This relative distance change can be measured to determine the displacement of the ground.

Here, the ground displacement measuring unit 310 is further provided with a pressure plate 313 on the outer edge of the drilling hole 1 to support the fixing portion 312.

Second, the axial force measuring unit 320 may be used to measure the change in the axial force of the fixing member 100 due to the displacement of the ground as the ground measuring unit 300.

Axial force measuring unit 320 is an accelerometer 321 is installed so as to be fixed to the edge of the drill hole (1) surrounding the outer periphery of the connecting member 200; and the stress generated in the connecting member 200 to the accelerometer 321 To be transmitted, the cap 322 is installed at the front end of the connecting member 200; is formed in a structure including (FIG. 5).

That is, by measuring the change in the axial force of the fixing member 100 due to the displacement of the ground generated in the connection member 200 installation area through the axial meter 321, to precisely determine the area and the size of the ground relaxation occurs I can figure it out.

Here, it is preferable that the axial force measuring unit 320 further installs a pressure plate 313 on the outer edge of the drilling hole 1 so as to support the axial force meter 321.

At this time, the cap 322 serves to close the accelerometer 321 to the pressure plate 313 to make a precise measurement.

As described above, since the ground measuring apparatus proposed by the present invention is installed in plural pieces by varying the installation depth of the fixing member 100, the installation region of the connecting member 200 is variously formed.

Accordingly, the present invention together presents a ground measuring structure formed of a plurality of ground measuring devices disposed in the relaxation region (a1, a2, a3, a4) of the different ground (Fig. 6).

In this case, in order to arrange the fixing members 100 at different depths, the fixing members 100 may be provided by installing connection members 200 having different lengths in the ground measuring apparatus.

Through this, it is possible to accurately measure the displacement of the ground and the change in the axial force of the fixing member 100 due to the depth for each depth.

The ground measurement method using the ground measurement structure is made as follows.

First, a plurality of drilling holes 1 are formed in the ground.

Next, a plurality of ground measuring devices are installed in the drilling hole 1 so that the fixing members 100 are located at different depths.

At this time, after the ground measuring device is installed, the pressure fluid 100A is supplied to the hollow of the fixing member 100 through the hollow of the connecting member 200 so that the ground measuring device is in close contact with the ground.

In this way, by installing the fixing member 100 of the ground measuring structure to be located at different depths of the ground, it is possible to precisely measure the loosening area of the ground, it is possible to ensure the stability of the structure in the appropriate contrast.

Then, after the ground measuring part 300 is installed at the outer edge of the drilling hole 1 and the front end of the connecting member 200, the ground measuring part 300 is used to displace the ground or thereby the fixing member 100. Measure the change in axial force.

In addition, the ground measurement method using the ground measurement structure can be effectively used in tunnel construction.

First, the ground is excavated in order to install a tunnel, and a plurality of drill holes 1 are formed in the shotcrete layer 2 and the back ground 3 formed in the excavation groove.

Then, a plurality of ground measuring devices are installed in the drilling hole 1 so that the fixing member 100 is located at different depths.

After the ground measuring device is installed, the pressure fluid 100A is supplied to the hollow of the fixing member 100 through the hollow of the connecting member 200 so that the ground measuring device is in close contact with the ground.

Next, the ground measuring unit 300 is installed at the front end of the connection member 200 formed on the surface of the shotcrete layer 2 to measure the displacement of the ground or the change in the axial force of the fixing member 100 due to the ground measuring unit 300. .

As such, when the ground measurement method using the ground measurement structure proposed in the present invention is used in tunnel construction, there is an advantage that the space of the tunnel to be installed can be formed relatively large.

In addition, there is an advantage that the tunnel to be installed can secure the strength and stability of the tunnel so that it can respond to the displacement of the ground or the change in the axial force of the fixing member 100 thereby.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the appended claims. It is to be understood that both the technical idea and the technical spirit of the invention are included in the scope of the present invention.

1: perforation hole 2: shotcrete layer
3: rear ground 10: conventional ground measuring device
11: main body of conventional ground measuring apparatus 12: sensor of conventional ground measuring apparatus
100: fixing member 100A: pressure fluid
200: connection member 300: ground measurement unit
310: ground displacement measuring unit 311: displacement sensor (LVDT)
312: fixing part 313: pressure plate
320: axial force measurement unit 321: axial force meter
322 cap

Claims (11)

A ground measuring device used to measure the displacement of the ground,
A fixing member 100 fixed to the inside of the drilling hole 1 formed in the ground;
A connection member 200 inserted into the drilling hole 1 and coupled to the outside of the fixing member 100;
On the outer edge of the drilling hole 1 and the front end of the connecting member 200 to measure the displacement of the ground occurring in the connection member 200 installation area or the change in the axial force of the fixing member 100 due to this Installed ground measuring unit 300;
Soil measuring apparatus comprising a. The method of claim 1,
The fixing member (100)
The pressure fluid 100A is formed to have a hollow to be injected and drained, and is pressed into the hollow of the fixing member 100 through the hollow of the connecting member 200 in a state in which a portion is pressed in a concave shape along the circumferential direction thereof. The ground measuring device, which is expanded by the supplied pressure fluid (100A) and made of a steel pipe. The method of claim 1,
The ground measuring unit 300
Ground displacement measuring unit 310 for measuring the displacement of the ground;
Soil measuring apparatus comprising a. The method of claim 3,
The ground displacement measuring unit 310
A displacement sensor (LVDT) 311 for measuring a change in relative distance from the front end of the connection member 200 exposed through the trim of the drilling hole 1;
Fixing portion (312) for fixing the displacement sensor (LVDT) 311 to the edge of the drilling hole (1);
Soil measuring apparatus comprising a. 5. The method of claim 4,
The ground displacement measuring unit 310
A pressure plate 313 installed at an outer edge of the drilling hole 1 to support the fixing part 312;
Ground measuring apparatus further comprises. The method of claim 1,
The ground measuring unit 300
Axial force measuring unit 320 for measuring the change in the axial force of the fixing member 100;
Soil measuring apparatus comprising a. The method according to claim 6,
The axial force measuring unit 320
An accelerometer 321 installed around the outer circumference of the connection member 200 and fixed to an edge of the drilling hole 1;
A cap 322 installed at the front end of the connection member 200 so that the stress generated in the connection member 200 is transmitted to the axial force meter 321;
Soil measuring apparatus comprising a. 8. The method of claim 7,
The axial force measuring unit 320
An acupressure plate 313 provided at an outer edge of the drilling hole 1 to support the axial system 321;
Ground measuring apparatus further comprises. A ground measuring structure using the ground measuring apparatus of any one of claims 1 to 8,
The plurality of ground measuring apparatuses are respectively installed in the plurality of drilling holes 1, and the plurality of fixing members 100 are disposed at different depths, and the connection member 200 is a relaxation region of different grounds. Ground measuring structure using a ground measuring device, characterized in that disposed on. A ground measuring method using the ground measuring structure of claim 9,
A drilling step of forming the plurality of drilling holes (1) in the ground;
Installing the ground measuring device in the drilling hole (1), the fixing member for each depth installation step for placing the fixing member 100 at different depths;
A ground measuring unit installing step of installing the ground measuring unit 300 at an outer edge of the drilling hole 1 and the front end of the connecting member 200;
A ground displacement measuring step of measuring a displacement of the ground using the ground measuring unit 300 or a change in the axial force of the fixing member 100 due to this;
Soil measurement method using a soil measurement structure comprising a. A ground measuring method using the ground measuring structure of claim 9,
A perforation step of forming the plurality of perforation holes (1) in the shotcrete layer (2) and the back ground (3) of the tunnel;
Installing the ground measuring device in the drilling hole (1), the fixing member for each depth installation step for placing the fixing member 100 at different depths;
A ground measuring unit installing step of installing the ground measuring unit 300 at a front end of the connection member 200 formed on the surface of the shotcrete layer 2;
A ground displacement measuring step of measuring a displacement of the ground using the ground measuring unit 300 or a change in the axial force of the fixing member 100 due to this;
Soil measurement method using a soil measurement structure comprising a.
KR1020120091301A 2012-08-21 2012-08-21 Apparatus for measurement of ground and method for measuring ground using the same KR20140025104A (en)

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KR1020120091301A KR20140025104A (en) 2012-08-21 2012-08-21 Apparatus for measurement of ground and method for measuring ground using the same

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Application Number Priority Date Filing Date Title
KR1020120091301A KR20140025104A (en) 2012-08-21 2012-08-21 Apparatus for measurement of ground and method for measuring ground using the same

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KR20140025104A true KR20140025104A (en) 2014-03-04

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110397092A (en) * 2019-05-14 2019-11-01 洛阳市轨道交通有限责任公司 Sandy gravel foundation pit displacement prediction method

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110397092A (en) * 2019-05-14 2019-11-01 洛阳市轨道交通有限责任公司 Sandy gravel foundation pit displacement prediction method

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