JPH10169362A - Tunnel excavation method and excavator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To excavate a fault fractured zone, etc., by driving an anchor towards a bedrock in the forward direction of an excavator from the inside of a tunnel excavator and propelling the excavator while taking reaction in the anchor. SOLUTION: When the TBM type excavator 1 taking reaction for propulsion in a peripheral bedrock by the gripper of a main body encounters a fault fractured zone, etc., an anchor body 8 is placed at a front end, and a hollow drill, into which a tension member 81 connected to the anchor body 8 is inserted, is penetrated to the bedrock in the front of a facing through the inserting hole 12 of a cutter face 11, and made to reach a firm bedrock section in the forward direction of the fault fractured zone while extending the hollow drills. The hollow drill is drawn from an excavated pit 9 while being disassembled, the anchor body 8 is expanded and fastened, the end section of the tension member 81 is gripped by a draw device 6, the tension member 81 is drawn near to the excavator side by the device 6, and a tunnel is excavated by rotating the cutter face 11 while taking the reaction of excavation. Accordingly, the fault fractured zone, etc., can be excavated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a tunnel excavation method and an excavator.

[0002]

In a conventional tunnel excavator such as a TBM (tunnel boring machine), when a fault crush zone or soft ground is encountered, a gripper reaction force cannot be taken on the ground. There was a problem that I could not dig. In that case, there is a method of excavating using a shield jack, but when excavating uncovered, a shield must be built.

In addition, the conventional body such as a TBM cannot predict the geology in front of the face, drain water or improve the ground. When the machine encounters a fault crush zone or soft ground, the excavator is retracted. Therefore, it is difficult to achieve high-speed excavation which is the original purpose of TBM.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and it is possible to excavate a fault crush zone or soft ground, and to predict the geology in front of the face, drain water, and improve the ground. It is an object of the present invention to provide a tunnel excavation method and an excavator that can also perform the tunneling.

[0005]

As a means for solving the above-mentioned problems, according to the present invention, an anchor is cast from the inside of the tunnel excavator toward the ground in front of the excavator. -A tunnel excavation method characterized in that an excavator is propelled while taking a reaction force.

According to a second aspect of the present invention, in the tunnel drilling method according to the first aspect, an anchor body is provided at a tip of the hollow drill, and a tension member having one end connected to the anchor body is inserted into the hollow drill. After inserting and excavating, the drill is removed, the anchor body is fixed to the tip of the hole, and a reaction force is applied to the anchor body via the tensile member to propel the excavator. To provide a tunnel excavation method.

According to a third aspect of the present invention, in the excavator used in the tunnel excavation method according to the second aspect, a drilling device for mounting and excavating the hollow drill, and tensioning of the driven anchor is provided. A tunnel excavator provided with a pulling device for drawing a material to an excavator side.

According to a fourth aspect of the present invention, in the tunnel excavator according to the third aspect, the tension device is mounted on a back surface of the cutter face via a bearing, and
A tunnel excavator, wherein the tunnel excavator is configured not to hinder the rotation of the tunnel excavator.

According to a fifth aspect of the present invention, in the tunnel excavator according to the third or fourth aspect, a chemical liquid injector for improving the ground through a hole drilled by the hollow drill is provided in the excavator. A tunnel excavator is provided.

[0010] Further, as claim 6, claims 3 to 5
The tunnel excavator according to any one of claims 1 to 3, wherein a drainage device for draining the ground through a drilled hole drilled by the hollow drill is provided in the excavator.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. <A> Structure of tunnel excavator TBM or the like can be used as the tunnel excavator of the present invention.

(1) Excavator Body The tunnel excavator 1 has a cylindrical outer shell, as shown in FIG.
One. An insertion hole 12 is formed at the center of the cutter face 11, and an opening / closing mechanism and a sealing mechanism (not shown) capable of opposing the earth pressure on the front face of the cutting face are provided.

(2) Drilling Device As the drilling device 2, a known boring machine or the like provided in the tunnel excavator 1 is used. As a drill to be used, a hollow drill 21 as shown in FIG. 4 is used. The hollow drill 21 can be extended to a predetermined driving length by being connected.

(3) Chemical injection device A known chemical injection device 3 for injecting a ground improvement agent is provided in the tunnel excavator 1 as shown in FIG.
The chemical injection device 3 has an injection tube (not shown) that is extendable or connectable, and is inserted into a hole drilled in the front of the face to improve the ground in front of the face.

(4) Drainage Facility As shown in FIG. 1, a drainage facility 4 is provided in the tunnel excavator 1, and excavated sediment taken in through a drain pipe 41 is rearward of the tunnel excavator 1. Can be transported to.

(5) Observation Camera As shown in FIG. 1, an observation camera 5 is provided in the tunnel excavator 1, and manages a drilling state, a liquid injection state, and the like.

(6) Tensioning device As shown in FIGS. 1 to 3, the tensioning device 6 is a device for gripping a tension material of an anchor disposed in a hole in the front of a face and drawing the material to the tunnel excavator 1 side. It is. This tension device 6
The well-known crunch etc. are used.

As shown in FIGS. 2 and 3, the tensioning device 6 is mounted on the back of the cutter face 11 via a ball bearing 7 so as not to hinder the rotation of the cutter face 11. The ball bearing 7 is formed in a ring shape, and the tensioning device 6 is supported on its surface by a plurality of legs.

(7) Anchor An anchor is formed by connecting one end of a tensile member 81 to an anchor body 8, as shown in FIGS. Anchor body 8
Shall have a structure that can be fixed to the excavated hole. For example,
Use a hydraulic packer or shape memory alloy that can be expanded and fixed after installation. Further, a wire or the like is used for the tensile member 81.

<B> Description of Tunnel Excavation Method Next, a tunnel excavation method using the tunnel excavator 1 configured as described above will be described.

(1) Drilling Step In a TBM type excavator, a reaction force for propulsion is generally applied to the surrounding ground by a gripper of a main body. However, excavation becomes difficult if the gripper encounters a fault crush zone or soft ground where a reaction force cannot be obtained.

Therefore, in the present invention, an anchor is installed in front of the face of the excavator, and the excavator is propelled by applying a reaction force to the anchor. As for the construction procedure, when a fault crush zone or the like is encountered, first, as shown in FIG.

The drilling method is as follows.
And through the insertion hole 12 of the cutter face 11 to penetrate into the ground in front of the face, and reach the solid rock in front of the fault crush zone while adding the hollow drill 21. At this time, the anchor body 8 is positioned at the tip of the hollow drill 21, and the tension member 81 connected thereto is inserted into the hollow drill 21.

(2) Draining Step Drilling water generated during excavation is transported to the rear of the excavator by the drainage unit 4 via the drainage pipe 41. Further, since a large amount of water is often supplied in a fault crush zone or soft ground, in such a case, the borehole 9 is used as a drain hole.

(3) Fixing of the anchor body After the excavation is completed, the hollow drill 21 is pulled out from the hole 9 while being disassembled, and the anchor body 8 left behind the hole 9 is expanded and fixed. The anchor body 8 is made of a material and fixing means capable of obtaining a sufficient excavation reaction force.

(4) Geological Prediction Excavation of the borehole 9 makes it possible to predict the geology ahead of the face from the excavation slip, the excavation time, the excavation sound and the like.

(5) Ground improvement The ground in front of the face is improved based on the result of the geological prediction. In this case, an injection pipe connected to the chemical injection device 3 is inserted into the hole 9 to inject the chemical. The observation camera 5 manages the state of drilling, the state of injection of a chemical solution, and the like.

(6) Propulsion The end of the tension member 81 inserted into the drilling hole 9 is gripped by the tension device 6. The pulling device 6 pulls the tensile material 81 toward the excavator to take the reaction force of the propulsion, while rotating the cutter face 11 to perform excavation. After the excavator gets out of the fault crush zone and reaches a solid rock part, the anchor and the tension device 6 are removed, and normal excavation is performed while taking a reaction force with the main body gripper.

[0029]

Since the present invention has been described above,
The following effects can be obtained. <B> Even if a fault crush zone or soft ground is encountered, TB
High-speed excavation, which is the original purpose of M, can be achieved, and the overall construction cost can be reduced.

<B> Prediction of the geology in front of the face, drainage and ground improvement can be performed without using the drilling hole for the anchor without retreating the excavator, and the construction period can be shortened.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a state in which the anchor is propelled with a reaction force.

FIG. 2 is an explanatory diagram of a main part of an excavator.

FIG. 3 is an explanatory view of the back of the cutter face.

FIG. 4 is an explanatory view of a state in which a hole for an anchor is being excavated.

Claims (6)

[Claims] 1. A tunnel excavation method comprising: placing an anchor from the inside of a tunnel excavator toward a ground in front of the excavator; and propelling the excavator while applying a reaction force to the anchor. 2. The tunnel drilling method according to claim 1, wherein an anchor is provided at a tip of the hollow drill, and a tensile member having one end connected to the anchor is inserted into the hollow drill to perform drilling. After performing, remove the drill and
A tunnel excavation method, comprising fixing a body to a tip of a drilled hole, and propelling an excavator by applying a reaction force to an anchor body via the tensile member. 3. An excavator used in the tunnel excavation method according to claim 2, wherein a drilling device for mounting and excavating the hollow drill is provided, and a tensile member of the installed anchor is provided on the excavator side. A tunnel excavator, which is equipped with a tension device for drawing to a tunnel. 4. The tunnel excavator according to claim 3, wherein the tension device is mounted on a back surface of the cutter face via a bearing so as not to hinder the rotation of the cutter face. , Tunnel excavator. 5. The tunnel excavator according to claim 3, wherein a chemical injection device for improving the ground through a drilled hole drilled by the hollow drill is provided in the excavator. Tunnel excavator. 6. The tunnel excavator according to claim 3, wherein a drainage device for draining the ground through a hole drilled by the hollow drill is provided in the excavator. And a tunnel excavator.