JPH08121080A - Underground boring method - Google Patents

Abstract

PURPOSE: To enhance the efficiency of shield hole formation by starting to advance a semishield excavator and a following pipe for assembling segments into the underground and then extruding a ring body assembled with the segments in the pipe by means of a shield jack. CONSTITUTION: A semi-shield machine 1 is installed to a starting shaft B where a main extrusion jack 31 is used to start. Then, a following pipe 2 for segment assembly is inputted into the starting shaft B. In this case, segments (a) are assembled inside the pipe 2 into a ring member A, which is extruded backward with a shield jack. Both the pipe 2 and the semi-shield machine 1 are moved forward and the main extrusion jack 31 supports the pipe 2 extruded with an initial ring member A and the reaction of the semi-shield machine 1 during advancing. Then, assembling and extrusion of the ring member A are repeated so as to form a desired length of shield hole, thereby removing the semi-shield machine 1 and the pipe 2 from an arrival shaft.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underground drilling method capable of efficiently forming a tunnel in the ground by a shield method by drilling with a shield machine.

[0002]

2. Description of the Related Art As a so-called tunnel construction method for piercing the ground, two construction methods, a shield construction method and a semi-shield construction method, are mainly adopted.

Both the shield construction method and the semi-shield construction method are
There are various methods depending on the excavation means, the shape of the shield hole, and the construction method, but the former shield construction method is generally the propelling part of the shield machine itself presses the ring body assembled inside this shield machine and advances. In the void created by this, the segment is assembled to re-form the above-mentioned ring body and the ring body is repeatedly extruded to form a tunnel in which the inner wall of the hole is lined by this ring body, that is, a shield hole is formed. Is a general term for.

In the latter semi-shielding method, the semi-shielding machine itself does not have a propulsion unit, and a cylindrical fume tube continuously arranged on the semi-shielding machine acts on the rear support wall provided at the starting position. This is a method of forming a tunnel, that is, a semi-shielded hole by a fume tube by advancing it integrally by the reaction force of the original push jack and sending it into the ground.

In the semi-shield construction method, when the thrust force is insufficient with only the original push jack, the intermediate push jack is preliminarily provided in the middle of the fume pipe, and the supporting pressure applied to the fume pipe as the distance becomes longer. However, it is possible to prevent the occurrence of cracks in the pipe due to exceeding the load bearing capacity in the axial direction of the pipe.

As described above, in the shield method, the ring segment-shaped "segments" can be assembled in the machine to form a ring body and can be dug, whereas in the semi-shield method, the original push jack at the starting position (further Forms a semi-shield hole by continuing to push in an integral tubular "fume tube" at the starting position using an intermediate press jack.

As is clear from the above, in the shield construction method, the propulsion force of the shield machine moves forward and the segments are assembled inside the machine. Therefore, the original push jack and the intermediate push jack at the starting position are used and the fume pipe is inserted at the starting position. Compared with the semi-shielding method, the long tunnel can be freely formed.

[0008]

However, the shield machine used in the shield construction method has a tail portion for assembling a segment into a ring body behind the excavation portion, and
Since it has a structure in which a propulsion unit having a seal jack for advancing is integrally provided, the total length of the shield machine is much longer than that of the semi-shielded machine, and therefore,
There is a problem that the starting shaft will become large, which will adversely affect underground buried objects and traffic conditions.

Further, in the shield method, there are cases where the shield shaft can be removed under the conditions such as the size of the reaching shaft, but normally the shield machine is usually buried, which is economically inferior to the semi-shield method. There is.

Therefore, an object of the present invention is to provide an underground drilling method capable of efficiently forming a safe and economical shield hole by combining the advantages of the shield method and the features of the semi-shield method. is there.

[0011]

In order to solve the above problems, the present invention relates to a semi-shield excavator having an excavation portion at the front end of a cylindrical outer shell base body, and this semi-shield excavator. It is a separate body, has a shield jack, and uses a segment assembly trailer pipe for internally assembling the segment into a ring body, and within the perforation formed by the launch of the semi-shielding machine and the subsequent segment assembly trailer pipe. , Segment assembly In a subsequent pipe, a ring body assembled by using a segment is pushed out by extension of a shield jack to form a shield hole.

[0012]

[Operation] A semi-shield excavator is thrown into the starting shaft, and it is started by using the original push jack, then a segment assembly subsequent pipe is thrown into the starting shaft, and this is followed by the semi-shield excavator with the original push jack. To start.

The segment assembly is performed by assembling the segments inside the trailing tube to form a ring body, and the ring body is pushed rearward by the shield jack to move the trailing tube and the semi-shield excavator forward.

The rear pipe by the initial extrusion of the ring body and the reaction force during the forward movement of the semi-shield excavator are supported by the original push jack. By repeating the assembly and extrusion of the ring body, the shield hole of the required length is obtained. Can be formed by removing the semi-shielding machine and the segment assembly trailer pipe from the reaching shaft.

[0015]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 1, the underground drilling method of the present invention uses a semi-shield excavator 1 and a segment assembly subsequent pipe 2 to assemble a segment a into a ring body A and push it out to proceed with excavation. The shield hole is formed by the shield method.

As shown in FIG. 2, the semi-shielding machine 1 is provided with an excavation portion 4 at the front end of a cylindrical outer shell substrate 3,
A working unit 5 and a machine operating unit 6 are formed in a row behind the excavation unit 4, and the excavation unit 4 drives a cutter 7 to rotate by a hydraulic motor 8.

The working unit 5 is provided with a conveyer such as a screw conveyor 10 or a belt conveyor whose front end faces between the cutter 7 and the partition plate 9, and the machine operation unit 6 has a control panel 11
And so on.

In the illustrated case, the outer shell substrate 3 is divided into a front portion 3a, an intermediate portion 3b and a rear portion 3c, and the front portion 3a and the intermediate portion 3 are divided into three parts.
In b, it is possible to excavate a bent and bent tunnel by selecting expansion and contraction of a plurality of curve jacks 12 each including a small stroke hydraulic cylinder.

In this way, the outer shell substrate 3 is divided into a plurality of parts,
When the joining and splitting are possible, the starting shaft B can be made small.

Next, the segment assembly subsequent tube 2 is, as shown in FIG. 3, a propulsion portion 14 inside a cylindrical outer shell 13 having an outer diameter equal to that of the outer shell base body 3 of the semi-shield excavator 1.
And a segment assembly portion 15 are provided.

The segment assembly portion 15 includes a cylindrical outer shell 13
Is formed by installing an erector 16 for assembling the segment a into the ring body A, and the tail portion 17 of the cylindrical outer shell 13 has a large inside diameter. A first tail seal 18 and a second tail seal 19 that are directed inward and inclined rearward are provided in front of and behind.

The tail seals 18 and 19 are formed of a single rubber material such as urethane rubber or a combination of leaf springs. The tail seals 18 and 19 press the outer peripheral surface of the ring body A in which the segment a is assembled to press the tail portion 17 and the ring. By sealing the space between the bodies A, it serves to prevent the intrusion of natural ground.

The propulsion portion 14 is located in the inner front half of the cylindrical outer shell 13 and is formed by a large number of shield jacks 20 arranged at regular intervals along the inner peripheral surface of the outer shell 13.

This shield jack 20 is shown in FIGS.
As shown in FIG. 2, a multi-stage cylinder such as a two-stage extension is used, and the base end is fixed to an annular end plate 21 provided at the tip of the cylindrical outer shell 13, and the annular body is circumferentially attached to the end that expands and contracts. A spherical head 2 for pushing the end of the ring body A through a jack spreader 22 divided into the number of shield jacks.
3 is provided. The center of the expansion / contraction direction of the spherical head 23 is set to match the center of the thickness of the segment a in the ring body A, and the extrusion of the ring body A by the shield jack 20 does not damage the segment a. I am able to do it.

Since the segment a is assembled in the tail portion 17, there is a difference in the tail clearance between the inner diameter of the tail portion 17 and the outer diameter D of the ring body A. the sum of the thickness (i.e., the difference between the outer diameter D ₁ of the outer diameter D and the shield machine 1 of the ring body a) is Teruboido is the filler c of the ring member a is backfilled when pushed out of the tail section It is filled, and thereby the ring body A is fixed. Further, since the segments a are tightly sealed by the seal, the secondary lining of the inner peripheral surface of the ring body A can be omitted.

Further, as the segment a, various segments such as concrete and steel plate made in accordance with each standard can be used, and a special one such as a curved portion can be selected according to the purpose. As illustrated, the ring body A
Is formed by a combination of a plurality of segments a divided in the circumferential direction, and the abutting end of one segment a ₁ in the circumferential direction and the segments on both sides of the segment a ₁ is an inwardly sloping inclined surface. In addition, the abutting end of the other one segment is a radial inclined surface with respect to the axis of the ring body A.

Next, the underground drilling method of the present invention will be described.

First, the semi-shield excavator 1 is loaded into the starting shaft B by suspending it with a crane or the like, and the original push jack 31 presses the excavator 1 into the ground. The shield machine 1 includes a front portion 3a and an intermediate portion 3a.
b, the rear part 3c may be divided, and the parts may be sequentially advanced to complete the assembly of the semi-shield excavator 1 in the ground, whereby the opening amount of the starting shaft B can be made small and the subdivision can be performed again. Thus, even if the reaching shaft has a small length, it can be taken out from the reaching shaft.

Next, the segment-assembled trailing pipe 2 is put into the starting shaft B by suspending it with a crane or the like, and the trailing pipe 2 is propelled by the original push jack 31 so as to be connected to the rear of the semi-shield excavator 1. .

As shown in FIG. 3, the rear end of the semi-shielding machine 1 and the front end of the segment assembly subsequent pipe 2 are connected via a large number of curve jacks 24 using hydraulic cylinders having a short stroke, and the semi-shielded. A curve can be cut between the excavator 1 and the succeeding pipe 2.

In this way, the reaction force of the push jack 31 acting on the rear support wall 32 provided in the starting shaft B for the semi-shield excavator 1 and the trailing pipe 2 and the semi-shield excavator 1
When integrally advanced by the excavation action of the segment a, the segment a is moved to the ring body A in the assembly portion 15 located in the latter half of the rear pipe 2.
Then, the ring body A is pushed rearward by the extension of the shield jack 20, whereby the semi-shield excavator 1 and the succeeding pipe 2 which are performing excavation are advanced.

In this shield construction method, the shield jack 2 is used every time the assembly work for each ring segment is completed.
0 is extended and the semi-shield excavator 1 and the succeeding pipe 2 are intermittently moved.

Immediately after the ring body A exits from the rear end of the succeeding tube 2, backfill injection is carried out for each ring body A, and the segments a are tightly sealed by a seal.

In the initial stage, the reaction force support during forward movement by the extension of the shield jack 20 of the semi-shield excavator 1 and the trailing pipe 2 is carried out by the original push jack, but if the shield hole becomes long, this shield will be used. The hole can support the reaction force, and the original push jack 31 can be removed from inside the starting shaft B, and the earth discharging work accompanying the excavation can be smoothly performed.

Further, as shown in FIG. 5, a mortar wound secondary lining layer b may be formed on the inner circumference of the shield hole formed by the continuous ring body A.

As described above, by using the semi-shield excavator 1 and the trailing pipe 2, the segment a is assembled into a ring shape to form the ring body A, and the ring body A is extruded and excavated to form a shield tunnel in the ground. be able to.

[0038]

As described above, according to the present invention, since the shield hole is formed by the shield construction method using the semi-shield excavator and the segment assembly subsequent pipe which is a separate body from the semi-shield excavator, the shield excavator It is possible to form a shield hole with a semi-shield excavator with a shorter overall length, and it is possible to construct the shield hole in a starting shaft with a small diameter, and it does not affect underground buried objects and traffic conditions. Become.

Further, the semi-shielding machine and the segment assembling subsequent pipe can be removed at the reaching shaft, and the economical efficiency is remarkably improved by reuse.

[Brief description of drawings]

FIG. 1 is a sectional view showing a construction state of an underground drilling method according to the present invention.

FIG. 2 is a vertical sectional view showing an example of a semi-shield excavator.

FIG. 3 is a vertical cross-sectional view of a segment assembly subsequent pipe.

FIG. 4 is a vertical cross-sectional view showing a shield jack portion of a segment assembly subsequent pipe.

FIG. 5 is a vertical sectional view of a shield hole.

[Explanation of symbols]

 1 semi-shield excavator 2 segment assembly subsequent pipe 3 outer shell base 20 shield jack a segment A ring body

Claims (1)

[Claims] 1. A semi-shield excavator having a tubular outer shell base body provided with an excavation portion at a front end thereof, and a semi-shield excavator which is a separate body from the semi-shield excavator and has a shield jack in which a segment is assembled into a ring body. For the shield jack, the ring body assembled by using the segment in the segment assembly subsequent pipe is installed in the hole formed by the start of the semi-shield excavator and the subsequent segment assembly subsequent pipe using the segment assembly subsequent pipe for By pushing out by extension,
Underground drilling method characterized by forming a shield hole.