JPH0579275A - Natural ground reinforcing execution method and device therefor - Google Patents

Abstract

PURPOSE:To reinforce natural ground by constructing a reinforing pile on the periphery of the excavated section of a tunnel, etc. CONSTITUTION:A pouring hole 3 is excavated in a propulsion direction from a pit face, and a reinforcing pipe 18 equipped with a strainer 20 and a sleeve 21 and a double pipe type pouring pipe 17 are inserted into a pouring hole 3, and water is sent into the reinforcing hole 18 from the outer pipe 22 of the pouring pipe 21 and the inside of the reinforcing pipe 18 is filled with water, and a hardening agent is jetted under high pressure from an inner pipe 23 into a bank 1 through the strainer 20. After the pouring and pulling-out are repeated alternately, the pouring pipe 17 is pulled out, and a reinforcing pie A which has the reinforced pipe 18 as core member and has an uneven outer shape is constructed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is effective in excavating mountain tunnels, urban tunnels, underground tunnels, etc., where soft ground, soft ground, etc. are likely to cause collapse or collapse, and ground subsidence. The present invention relates to a ground reinforcement method for improving safety and a ground reinforcement device used therefor.

[0002]

2. Description of the Related Art Conventionally, in excavation of natural ground in tunnel construction, etc., the excavated cross section of a face is divided into several parts, and each of the divided cross sections is collapsed by empirical techniques while visually observing each divided cross section. The construction method of excavating while preventing collapse, providing support work, and excavating is adopted, and the construction method that takes planned stabilization measures from the face of the face to the depth of the ground is not generally implemented, Especially in soft ground, the upper part of excavated section was reinforced by sheet pile or osmotic injection method.

[0003]

In the general excavation method, collapse prevention and collapse prevention, face stabilization measures, ground subsidence prevention, water stop measures, etc. were implemented as individual countermeasures. There is nothing to improve safety other than shortening the work time from one excavation to the next excavation as much as possible, and there are many ground collapses and collapses during excavation, giving underground workers great environmental and psychological anxiety. ..

Further, it is troublesome to carry out a work for individually dealing with such a natural ground, and the efficiency of excavation work is reduced. Since the method of injecting into osmotic pressure generally has low strength and it is difficult to determine the reinforcing effect of the natural ground, a large amount of injection is often performed to ensure safety during excavation, which increases the construction cost.

The present invention is to solve the above-mentioned problems in tunnel excavation work, and to improve the safety of excavation work by continuously constructing a reinforcing pile in advance at the top and the periphery of the face of a tunnel or the like. It is an object of the present invention to provide a mountain reinforcement method and a ground reinforcement device used in this method.

[0006]

According to the present invention, after the injection hole is drilled from the face in the direction of excavation along the periphery of the excavated section of a tunnel or the like, a strainer and a sleeve for covering the strainer are provided at a predetermined pitch. A reinforcing pipe, and an outer pipe in which openings are arranged on the side surface according to the pitch of the strainer and a packer is attached between the openings at the same pitch, and an inner pipe having a nozzle at the tip, and the reinforcing pipe is mounted in the reinforcing pipe. Insert a double-tube type injection pipe into the injection hole, feed water to the outer pipe to fill the reinforcing pipe with water, then pressure-feed the hardener to the inner pipe, and a predetermined amount of hardener from the nozzle to the ground. After the injection of the curing agent and the withdrawal of the inner tube are alternately repeated to inject the inner tube by the above-mentioned pitch, the injection of the predetermined length is completed, and then the injection tube is withdrawn from the reinforcement tube. Is used as the core material and has an uneven outer shape To construct a strong pile to reinforce the natural ground.

The ground improvement device of the present invention is an excavation device in which a horizontal leader equipped with a boring drive mechanism capable of moving forward and backward is tilted forward and backward, leftward and rightward, and supported on a trolley by a position setting mechanism that is expandable and contractible. The boring drive mechanism arranges the drilling rod, the strainer and the sleeve covering the strainer with a predetermined pitch at the reinforcing pipe, and the side surface with the opening at the pitch of the strainer and at the same pitch. A double-tube injection pipe consisting of an outer pipe with a packer attached and an inner pipe with a nozzle at the tip, with a water supply pipe connected to the outer pipe and a hardening agent supply pipe connected to the inner pipe. I am configuring.

[0008]

[Operation] At the time of injection, the curing agent sprayed from the nozzle is
It passes through the opening on the side of the outer pipe of the injection pipe and reaches the strainer of the reinforcing pipe. There, the pressure of the curing agent destroys the sleeve covering the strainer, and the curing agent is injected into the ground. At this time,
Since the front and rear openings of the outer tube are blocked by a packer and the rear reinforcing tube is filled with water, the hardening agent is injected into the natural ground only from the strainer corresponding to the position of the nozzle. Therefore, by alternately repeating the drawing of the inner pipe at a predetermined pitch and the injection of the curing agent, the position of the strainer has a large diameter, the intermediate position between the strainer and the strainer has a small diameter, and the outer shape corrugates in the excavation direction. A reinforcing pile having unevenness is formed.

By continuously arranging the reinforcing piles along the excavation cross-section of a tunnel or the like, an arch-shaped improvement body is formed, and the stability of the face is ensured by preserving the face deeply in the direction of excavation. Collapse and collapse are prevented. Since this reinforcing pile has the above-mentioned shape, a large strength can be obtained especially with respect to the displacement of the natural ground in the axial direction.

[0010]

EXAMPLE FIG. 1 is a side view of the ground reinforcement method of the present invention, and FIG.
FIG. Here, the ground reinforcement device 10 is provided with a position setting mechanism 14 including a universal joint 12 and a hydraulic cylinder 13 tilted back and forth and left and right by the universal joint 12 at the front and rear portions of the bogie 11. A horizontal leader 16 having a boring drive mechanism 15 mounted on the upper end of the cylinder 13 so as to be able to move forward and backward.
I support you. The boring drive mechanism 15 incorporates a chuck (not shown) having a variable inner diameter, and a drilling rod (not shown), a reinforcing pipe 18, and an injection pipe 17 can be attached thereto. The dolly 11 is provided with an outrigger 40 for stabilizing the work and a movable scaffold 41 for work.

The reinforcing pipe 18 is, as shown in FIGS. 3 and 4,
Strainer 20 and sleeve 2 covering this strainer 20
1 are provided at a predetermined pitch P, and the cap 18 is provided at the rear end.
0 is screwed on. The injection pipe 17 includes an outer pipe 22 and an inner pipe 2
It is a double tube consisting of 3 and 3. The outer pipe 22 is provided with openings 24 in accordance with the pitch P of the strainer 20, and a packer 25 shown in FIG. 5 is attached between the openings 24 at the same pitch P. A water supply pipe 27 is connected to the rear end of the outer pipe 22 via an outer pipe swivel 26. A nozzle 28 is provided at the tip of the inner pipe 23, and a curing agent supply pipe 30 is connected to the rear end of the inner pipe 23 via an inner pipe swivel 29.

The injection pipe 17 is mounted in the reinforcing pipe 18 so that the peripheral edge 250 of the packer 25 is in pressure contact with the inner wall 181 of the reinforcing pipe 18. The gauge pipe 31 for measurement is led out from the cap 180 of the reinforcing pipe 18.
A pressure gauge 32 is connected to. When excavating a tunnel in the ground 1, a ground improvement area is defined in advance according to the state of the ground, and a pouring hole 3 of a predetermined length is drilled in the direction of excavation from the face 2 along the periphery of the excavation cross section, and a hardening agent is applied. Inject.

At the time of drilling, the bogie 11 is fixed by the outrigger 40, the position setting mechanism 14 moves the horizontal leader 16 to set the position and direction of the drilling rod, and the boring drive mechanism 15 is started. When the drilling of the injection hole 3 is completed, the boring drive mechanism 15 is retracted to extract the drilling rod, and the reinforcing pipe 18 and the injection pipe 17 are inserted into the injection hole 3. After the insertion, water is fed from the water supply pipe 27 into the outer pipe 22 through the outer pipe swivel 26 to fill the reinforcing pipe 16 with water,
A high-pressure curing agent is supplied from the curing agent supply pipe 30 to the inner pipe 23 via the inner pipe swivel 29. The curing agent is sprayed from the nozzle 28, passes through the opening 24 of the outer pipe 22, and reaches the strainer 20 of the reinforcing pipe 18. Then, the sleeve 21 is broken by the pressure of the curing agent, and the curing agent is injected into the ground 1.
At this time, since the front and rear openings are blocked by the packer 25, and the rear reinforcement pipe 18 is filled with water, the injection of the curing agent into the natural ground 1 corresponds to the position of the nozzle 28. Only done from strainer 20. The injection of the predetermined pitch P of the inner pipe 23 and the injection of the curing agent are alternately repeated from the front end of the injection pipe 3, and when the injection of the predetermined length is completed, the entire injection pipe 17 is removed by the boring drive mechanism 15. Pull out from the injection hole 3. In the ground 1, a reinforcing pipe 18 having a reinforcing pipe 18 as a core material and an outer shape having corrugated unevenness in the excavation direction is formed. When one pile formation is completed, the position setting mechanism 14 moves the horizontal leader 16 to attach the drilling rod to the boring drive mechanism 15, after drilling the next injection hole, the curing agent is injected again in the same manner. To do. By continuously constructing the reinforcing pile in a predetermined range in this manner, an arch-shaped reinforcing body can be formed.

The pressure of the curing agent, the injection amount, the pitch of the strainer, etc. are set according to the strength of the natural ground, design conditions, and the like. Generally, the curing agent is injected at 200 to 900 kgf / cm ² , so that the sleeve is designed to be broken at a lower pressure.

[0015]

As described above, according to the ground reinforcement method of the present invention, a reinforcing pile having high strength is efficiently formed at the top and the periphery of the tunnel face so that the face is deeply advanced from the face to the digging direction. A ground reinforcement to be received can be formed, the face can be stabilized, and collapse, collapse, and water discharge can be prevented, and safety can be improved.

The ground reinforcement device of the present invention comprises a drilling rod,
Both the reinforcing pipe and the injection pipe can be attached, and by using this device, a reinforcing pile having a core as the reinforcing pipe and an uneven outer shape can be easily formed.

[Brief description of drawings]

FIG. 1 is a side view of an embodiment of the present invention.

2 is a rear view of the embodiment of FIG.

FIG. 3 is a vertical cross-sectional view of a reinforcing pipe and an injection pipe.

4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is a side view of the packer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ground 2 Face 3 Injection hole 10 Earth reinforcement device 11 Cart 12 Universal joint 13 Hydraulic cylinder 14 Position setting mechanism 15 Boring drive mechanism 16 Horizontal leader 17 Injection pipe 18 Reinforcement pipe 20 Strainer 21 Sleeve 22 Outer pipe 23 Inner pipe 24 Opening 25 Packer 26 Swivel for outer pipe 27 Water supply pipe 28 Nozzle 29 Swivel for inner pipe 30 Curing agent supply pipe A Reinforcement pile

Claims (2)

[Claims] 1. Along the periphery of an excavated section such as a tunnel,
After drilling the injection hole from the face in the direction of excavation, a reinforcement pipe provided with a strainer and a sleeve covering the strainer at a predetermined pitch, and an opening is provided on the side surface in accordance with the pitch of the strainer and opened at the same pitch. A double-tube type injection pipe, which is composed of an outer pipe having a packer attached between them and an inner pipe having a nozzle at the tip and is mounted in the reinforcing pipe, is inserted into the injection hole, and water is supplied to the outer pipe. After filling the reinforced pipe with water,
The curing agent is pressure-fed to the inner pipe, a predetermined amount of the curing agent is injected and injected from the nozzle to the ground, and the inner pipe is pulled out by the pitch, and thereafter injection and injection of the curing agent and withdrawal of the inner pipe are alternately repeated. After the injection of a predetermined length is completed, the injection pipe is pulled out from the reinforcement pipe, and the reinforcement pipe is used as a core material to form a reinforcement pile having an uneven outer shape. 2. A boring device in which a horizontal leader equipped with a boring drive mechanism capable of moving forward and backward is tilted forward and backward, left and right, and supported on a trolley by a position setting mechanism that is capable of expanding and contracting. Is a rod for drilling, a reinforcing pipe provided with a strainer and a sleeve covering the strainer at a predetermined pitch, and an opening is provided on the side surface according to the pitch of the strainer, and a packer is attached between the openings at the same pitch. It is composed of an outer pipe and an inner pipe with a nozzle at the tip, and a double pipe type injection pipe in which a water supply pipe is connected to the outer pipe and a hardening agent supply pipe is connected to the inner pipe can be installed ..