KR20180086998A - Ground improvement system by high pressure jet grouting - Google Patents

Abstract

The present invention relates to a high pressure injection grouting ground improvement system that is configured to insert a guide pipe to which a sensor sensing vibrations caused by high pressure injection into a target improvement radius point upon ground improvement, thereby in real time checking an injection diffusion range. According to the present invention, the high pressure injection grouting ground improvement system includes: a high pressure injection rod for supplying compressed air, or compressed air and ultra-high pressure water, and cement paste or mortar; a monitor disposed on the lower end periphery of the high pressure injection rod in such a manner as to be inserted into the ground to be improved to inject the compressed air or the compressed air and ultra-high pressure water at a high pressure, to cut off the ground, to inject the cement paste or mortar, and to form a cylindrical hardened body in the ground; a guide pipe inserted into a point in the ground within a target improvement radius (Rt); and a sensor coupled to one side of the guide pipe to sense vibrations caused by the high pressure injection.

Description

Field of the Invention [0001] The present invention relates to a high pressure jet grouting system,

The present invention relates to a high pressure injection grouting ground improvement system capable of confirming an injection diffusion range in real time by inserting a guide pipe coupled with a detection sensor capable of detecting vibration due to high pressure injection at a target improvement radius point in the ground improvement.

Conventionally, in order to fill voids in the cavity or sand gravel layer of the conventional ground, to improve the soft layer or to improve the underwater ground of the fly ash for the construction of underwater structures, a high pressure injection rod made of a double pipe or a triple pipe, A high pressure spray grouting ground improvement system is used which injects a coagulant such as a high pressure gas into the ground.

1, the monitor 3 coupled to the lower end of the high-pressure injection rod 2 is inserted into the ground 1 to be improved, and the ground is rotated while jetting the compressed air or compressed air and the ultra-high- After cutting, cement paste or mortar is sprayed to form a cylindrical solid body (6) in the ground.

Specifically, by injecting compressed air and cement paste or mortar at a high pressure using a double pipe rod with a high-pressure injection rod 2, the ground pile and the like in the ground and the coagulant are stirred and mixed to form a cylindrical solidified body 6.

Or injection of ultra-high pressure water as well as cement paste or mortar using a triple-tube rod with a high-pressure injection rod (2) to cut and agitate the ground so that very small particle components such as clay are discharged to the ground, The soil or the like and the condensing agent are stirred and mixed to form the columnar solidified body 6.

However, since such a cylindrical solid body 6 is formed in the ground, it is difficult to confirm whether or not the radius of the cylindrical solid body 6 is equal to or larger than the actually planned target improvement radius.

KR 10-0942714 B1

In order to solve the above-mentioned problems, the present invention provides a high pressure spraying device capable of confirming whether the ground is improved up to the target improvement radius point when a high-pressure spray is formed in the ground by a high- Grouting soil improvement system.

According to a preferred embodiment of the present invention, there is provided a high pressure injection rod for supplying compressed air or compressed air and ultrahigh pressure water and cement paste or mortar; Pressure injection rod to be inserted into the ground to be improved to inject compressed air or compressed air and ultra-high-pressure water at a high pressure to cut the ground, and spray cement paste or mortar to form a cylindrical solidified body in the ground monitor; A guide pipe inserted at a point within the ground of the target improvement radius (R _t ); A sensing sensor coupled to one side of the guide tube and sensing vibration due to high pressure injection; The present invention provides a high pressure injection grouting ground improvement system capable of confirming an injection diffusion range.

According to another preferred embodiment of the present invention, there is provided a high pressure injection grouting ground improvement system capable of confirming an injection diffusion range, wherein the sensing sensor is attached inside a guide pipe.

According to another preferred embodiment of the present invention, the guide tube is provided with an expandable pack which can expand and contract in volume, a fixing band is provided outside the expansion pack, and the sensing sensor is coupled to the outside of the fixing band The present invention provides a high pressure injection grouting soil improvement system capable of confirming the injection diffusion range.

According to another preferred embodiment of the present invention, the fixing band is composed of a plurality of fixing plates to which the sensing sensors are attached and a connecting member of an elastic material for mutually connecting the adjacent fixing plates. A grouting ground improvement system is provided.

According to another preferred embodiment of the present invention, there is provided a high-pressure injection grouting ground improvement system capable of confirming an injection diffusion range, wherein a pull wire is coupled to an upper portion of the expansion pack.

According to another preferred embodiment of the present invention, there is provided a high pressure injection grouting ground improvement system capable of confirming an injection diffusion range, wherein the sensing sensor is a strain gage.

According to another preferred embodiment of the present invention, there is provided a high pressure injection grouting soil improvement system capable of confirming an injection diffusion range, wherein the sensing sensor is a pressure sensor.

According to another preferred embodiment of the present invention, the monitoring unit includes a monitoring unit for collecting measured values sensed by the sensing sensor, and the monitoring unit displays a diffusion range of solidification according to the magnitude of the sensed measured value. Provides a high pressure injection grouting soil improvement system that can confirm the range.

According to the present invention, in a ground improvement system in which a columnar high-rigidity is formed in the ground by high-pressure injection, a guide pipe having a sensing sensor capable of detecting vibration due to high- The cutting state can be grasped.

Conventionally, the composition diameter and the improvement state were confirmed by the boring irradiation after completion of the solidification work. However, according to the present invention, it is possible to grasp the solidification diameter during the construction and determine whether the soil improvement work is progressed according to the degree of work, It can be made more efficient, thereby improving workability and economical efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a sectional view showing a conventional high pressure injection soil improvement method. Fig.
Figure 2 is a cross-sectional view of a high pressure spray grouting soil improvement system capable of confirming the injection diffusion range of the present invention.
Figure 3 is a cross-sectional view of a guide tube with an internal sensing sensor.
4 is a longitudinal section of a guide tube having an expansion pack with a sensor attached thereto;
5 is a longitudinal sectional view showing the operation of the detection sensor according to the expansion of the expansion pack.
6 is a perspective view of an inflated pack with a fixed band;
7 is a cross-sectional view showing a pulled state of the expansion pack proceeding according to the pull of the monitor.
8 is a graph showing measured values measured by the sensing sensor in the monitoring section.

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

2 is a cross-sectional view of a high pressure injection grouting soil improvement system capable of confirming the injection diffusion range of the present invention.

As shown in FIG. 2, the high pressure injection grouting ground improvement system capable of confirming the injection diffusion range of the present invention comprises a high pressure injection rod 2 for supplying compressed air or compressed air and ultrahigh pressure water and cement paste or mortar; Pressure injection rod 2 and is inserted into the ground 1 to be improved so that compressed air or compressed air and ultra-high-pressure water are injected at a high pressure to cut the ground 1 and spray cement paste or mortar, A monitor (3) for forming a solidified body (6) in the ground (1); A guide pipe (4) inserted at a point in the ground (1) of the target improving radius (R _t ); And a sensing sensor (5) coupled to one side of the guide tube (4) and sensing vibration due to high pressure injection; . ≪ / RTI >

The high pressure injection rod 2 may be composed of a double pipe rod for supplying compressed air and cement paste or mortar to the ground or a triple pipe rod for supplying compressed air and ultrahigh pressure water and cement paste or mortar.

The monitor 3 is provided at the lower end of the high-pressure injection rod 2 and inserted into the ground 1 to be improved.

The monitor 3 cuts the ground 1 by injecting compressed air or compressed air and ultra-high-pressure water at a high pressure. Then, cement paste or mortar is sprayed and mixed with a ground pile soil or the like in the ground 1 so that a cylindrical solid foundation 6 can be formed in the ground to a predetermined size.

The guide tube 4 is inserted at a point within the ground 1 of the target improving radius R _t .

Since the high-pressure injection rod 2 and the monitor 3 spray the compressed air or compressed air and the ultra-high-pressure water while rotating, the guide pipe 4 is installed at only one of the positions of the target improving radius R _t . However, since the ground cutting range may not be circular depending on the ground 1 condition, it is preferable to insert the guide pipe 4 at a plurality of points of the target radius of curvature R _t .

The sensing sensor 5 is coupled to one side of the guide tube 4 to sense vibration due to high-pressure injection.

Accordingly, when the cutting range of the ground 1 is increased by high-pressure injection and the diffusion range reaches the point of the target improving radius R _t , compressed air or ultra high pressure water directly hits the guide pipe 4, 5).

Therefore, the ground cutting condition can be grasped in real time.

If it is confirmed that the cut range is different from the target radius of curvature (R _t ), cement paste or mortar is injected through the monitor 3 to form a cylindrical solid body 6 with a predetermined size in the ground.

The measurement value sensed by the sensing sensor 5 can be collected by the external monitoring unit 7 and confirmed by the operator.

As described above, in the present invention, the injection diffusion range of the compressed air or the ultra-high pressure water can be confirmed in real time by inserting the detection sensor 5 capable of detecting the vibration by the high pressure injection at the point of the target improving radius R _t .

The sensing sensor 5 may be a strain gauge.

The detection sensor 5 can use a sound collector capable of detecting a cutting sound and confirming a cutting range. However, there is a possibility that an error may occur in the confirmation of the cutting range because the impact sound may be diffused according to the ground (1) condition.

Therefore, it is preferable to use a strain gauge as the sensing sensor 5 to sense the vibration by a direct blow.

Generally, a strain gauge measures a strain using a change in electric resistance value caused by a change in the length and cross-sectional area of a strain gauge when a strain is applied to a measurement object to which the strain gauge is attached. These strain gauges are likely to generate noise in the measured values when an external force is applied.

In the present invention, the cutting range is set to the target improving radius (R _t ) by using the noise of the measured value generated when the impact generated when the ground 1 is cut by the high-pressure injection is transmitted to the guide pipe 4 or the strain gauge Can be confirmed.

The sensing sensor 5 may be a pressure sensor.

That is, a pressure sensor capable of sensing the pressure applied to the guide tube 4 can be used as the sensor 5.

Examples of the pressure sensor include a FSR (Force Sensing Resistor) sensor composed of a polymer film whose resistance decreases when a force is increased on a surface of a sensor, a piezo sensor including a thin piezoelectric element inserted between metal plates, Type sensor can be used.

Fig. 3 is a cross-sectional view of a guide tube having a detection sensor attached thereto.

As shown in FIG. 3, the detection sensor 5 can be attached to the inside of the guide pipe 4. [

Typically, the film-type sensor 5 is fixed to the mounting surface by using an adhesive, and a protective tape is attached to the outside thereof to prevent damage.

However, when the detection sensor 5 is attached to the outside of the guide pipe 4, the detection sensor 5 attached to the outside of the guide pipe 4 when the ground 1 is inserted may be detached.

Therefore, the detection sensor 5 is attached to the inside of the guide tube 4 in order to prevent the detection sensor 5 from falling off.

3 (a), the guide tube 4 is cut in half, that is, into semicircles 4a and 4b, and then the detection sensors 5 are attached to the inside of the semicircles 4a and 4b, The semicircles 4a and 4b of the pair can be welded to each other as shown in FIG. 3 (b).

A plurality of detection sensors 5 may be installed in the guide tube 4 in a plurality of directions to detect the injection diffusion range irrespective of the direction in which the guide tube 4 is inserted.

A gauge lead (not shown) may be connected to the detection sensor 5, and the gauge lead may transmit a measurement signal to the monitoring unit 7.

FIG. 4 is a vertical sectional view of a guide tube having an expansion pack with a sensor attached thereto, and FIG. 5 is a longitudinal sectional view showing an operation process of the detection sensor according to the expansion of the expansion pack.

4, the guide tube 4 is provided with an expansion pack 8 capable of expanding and contracting in volume, a fixing band 9 is provided outside the expansion pack 8, And the detection sensor 5 may be coupled to the outside of the band 9.

When the guide pipe 4 is divided into the semicircular parts 4a and 4b and the detection sensor 5 is attached to the inner side surfaces of the semicircular parts 4a and 4b and welded together as in the embodiment of FIG. It is difficult to attach the detection sensor 5 to the vicinity of the junction of the adjacent semicircular elements 4a and 4b due to damage of the strain gauge caused by the welding heat or the like.

Accordingly, there is a limit to the attachment direction of the detection sensor 5.

Therefore, by providing the detection sensor 5 outside the expansion pack 8, it is possible to detect the vibration as the detection sensor 5 is brought into close contact with the inner surface of the guide tube 4 by the expansion of the expansion pack 8 Can be configured.

In this case, since the process of cutting and re-welding the guide pipe 4 is omitted, the installation is convenient, and the detection sensor 5 can be arranged as necessary in various directions of the guide pipe 4, thereby improving the accuracy.

The expansion pack 8 can be injected or discharged with air by using an injection pipe 81 connected to one side of the expansion pack 8.

That is, when air or the like is injected into the expansion pack 8 using the injection tube 81 to expand the expansion pack 8, the fixing band 9 provided outside the expansion pack 8 is expanded Expanding with the expansion of the pack 8. The detection sensor 5 coupled to the outside of the fixing band 9 is brought into close contact with the inner surface of the guide pipe 4. When the compressed air or ultra high pressure water hits the guide pipe 4 directly, Vibration is detected.

6 is a perspective view of an expansion pack with a fixed band.

6, the fixing band 9 includes a plurality of fixing plates 91 to which the detection sensors 5 are attached and a connecting member 92 of elastic material for mutually connecting the adjacent fixing plates 91 Can be configured.

When the fixing band 9 is expanded in accordance with the expansion of the expansion pack 8, the fixing band 9 may be excessively deformed and the sensing sensor 5 may be detached from the fixing band 9.

Therefore, when the detection sensor 5 is attached to the fixing plate 91 having a fixed size and the adjacent fixing plate 91 is connected to the elastic connecting member 92 having a length that is freely stretchable, The detection sensor 5 can be securely attached and supported without being detached from the fixed band 9. [

7 is a cross-sectional view showing the pulled-up state of the expansion pack proceeding with the withdrawal of the monitor.

As shown in FIGS. 5 to 7, the pulling wire 82 can be coupled to the upper portion of the expansion pack 8.

When the ground 1 is improved using the high pressure spray grouting ground improvement system of the present invention, the upward work is progressed while pulling out the high pressure injection rod 2 and the monitor 3 to the upper part.

Accordingly, in order to confirm the injection diffusion range by depth, the guide pipe 4 should be pulled out like the high-pressure injection rod 2 and the monitor 3, or a plurality of detection sensors 5 should be attached to the guide pipe 4 per depth .

However, separate equipment is needed to pull out the guide tube (4). Further, in order to attach the plurality of sensors 5 to the guide tube 4 by depth, the cost of the sensor 5 increases, which is uneconomical.

Therefore, the expansion pack 8 provided inside the guide tube 4 and the sensing sensor 5 coupled thereto are elevated in accordance with the rise of the monitor 3, thereby confirming the injection diffusion range for each depth.

The expansion pack 8 is lifted up to the upper part after the shrinkage and is expanded again at the injection position so that the sensing sensor 5 is closely contacted with the inside of the guide pipe 4, Check.

The expansion pack 8 is pullable upward by a pulling wire 82 coupled to the top and the pulling wire 82 is pullable by a pulling force or a driver.

8 is a graph showing measured values measured by the sensing sensor in the monitoring section.

When the measured value reaches the target value A _T as shown in FIG. 8, it is regarded that the solidification 6 reaches the target improving radius R _t , and the grouting work at the corresponding position is stopped .

In addition, the monitoring unit 5 may display the diffusion range of the solid solution 6 according to the magnitude of the measured value.

That is, it is also possible to confirm the diffusion state and diffusion rate of the solidification 6 according to the change in the measured value.

1: Ground
2: High pressure injection rod
3: Monitor
4, 4a, 4b: guide tube
5: Detection sensor
6: Cylindrical solidification
7: Monitoring section
8: Expansion pack
81: Injection tube
82: pull wire
9: Fixed band
91: Fixing plate
92: connecting member

Claims (8)

A high pressure injection rod (2) for supplying compressed air or compressed air and ultrahigh pressure water and cement paste or mortar;
Pressure injection rod 2 and is inserted into the ground 1 to be improved so that compressed air or compressed air and ultra-high-pressure water are injected at a high pressure to cut the ground 1 and spray cement paste or mortar, A monitor (3) for forming a solidified body (6) in the ground (1);
A guide pipe (4) inserted at a point in the ground (1) of the target improving radius (R _t ); And
A sensing sensor (5) coupled to one side of the guide tube (4) and sensing vibration due to high pressure injection; And a high pressure spray grouting ground improvement system capable of confirming an injection diffusion range.
The method of claim 1,
Characterized in that the sensing sensor (5) is attached inside the guide tube (4).
The method of claim 1,
An expansion pack 8 capable of expanding and contracting in volume is provided in the guide tube 4 and a fixing band 9 is provided outside the expansion pack 8, Wherein the detection sensor (5) is coupled to the high pressure injection grouting ground improvement system.
4. The method of claim 3,
Wherein the fixing band 9 is composed of a plurality of fixing plates 91 to which the detection sensors 5 are attached and a connecting member 92 of an elastic material for mutually connecting the adjacent fixing plates 91. [ High pressure injection grouting ground improvement system which can confirm the range.
4. The method of claim 3,
Characterized in that a pull wire (82) is coupled to the top of the expansion pack (8).
The method of claim 1,
Characterized in that the sensing sensor (5) is a strain gauge.
The method of claim 1,
Characterized in that the sensing sensor (5) is a pressure sensor.
The method of claim 1,
And a monitoring unit 7 for collecting measured values sensed by the sensing sensor 5. The monitoring unit 5 may be configured to display the diffusion range of the solidification 6 according to the magnitude of the sensed measurement value High pressure injection grouting ground improvement system which can confirm injection spread range.

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