JP2584127B2 - Tunnel connection method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial application field> The present invention relates to a final step of opening the tip of a new tunnel to an existing tunnel without destruction of the surrounding ground or existing tunnel structure, and the present invention. The present invention relates to a tunnel connection method capable of assuredly penetrating a building while minimizing the effect on traffic inside the building.

<Conventional technology> Crossing the existing tunnel in use and newly evacuating,
There may be new tunnels for communication or ventilation.

When the existing tunnel is formed by excavating a relatively hard rock such as a mountain tunnel, when excavating a new tunnel, it is possible to excavate while crushing the rock by a blasting method or the like to a position near the connection position of the existing tunnel. .

However, if the blasting is performed in the final step, that is, when the excavation of the new tunnel has progressed to the vicinity of the intersection with the existing tunnel, the impact on the existing tunnel structure due to the vibration, noise, and scattering of rock etc. Is big.

In addition, since the existing tunnel has a certain amount of traffic even during construction, it is extremely dangerous considering the potential impact on third parties who pass through the tunnel during blasting.

Therefore, in the vicinity of the connection position, there are various excavation methods described in the following (a) to (d) as alternatives to the blasting method, but all have problems.

<Problems to be solved by the invention> (A) Crushing method using a static crushing agent: It takes time and the crushing effect is not constant. Reinforced structures cannot be crushed and have safety problems.

(B) Water jet method: The rock drilling depth is limited and inefficient.

(C) Slot drilling: In addition to the large size of the machine, there are restrictions on the section used, and vibration and noise are involved.

(D) Breaker: Small machines have limited rock breaking capacity, and are accompanied by noise and vibration during work.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and enables the use of a small-sized device, and a tunnel connection for excavating a connection position between the two tunnels without significantly affecting the surrounding ground, the structure of the existing tunnel, and traffic. It provides a construction method.

<Means for Solving the Problems> In order to achieve the above-mentioned object, this invention method involves drilling a ground for isolating a connection between the two tunnels in the final excavation step of a new tunnel dug toward an existing tunnel. A plurality of holes are formed between the tunnels, and a wire saw is inserted in a loop between adjacent holes through the existing tunnel. The tension is applied to the wire saw, and the wire saw is driven endlessly to rotate the wire saw. By pulling the wire saw in a tunnel, a cutting operation is performed along a line connecting the conductive holes, and the cutting operation is repeated to separate the isolated ground from the peripheral ground.

Further, in the method of the present invention, after the isolation ground is separated from the surrounding ground, the wire saw is inserted between the opposed vertical or horizontal conductive holes, and cut along a line connecting the conductive holes. The isolation ground is divided into a plurality of vertical and horizontal blocks.

Further, at the time of dividing the block, at least one side of the block is connected, the bottom of the block is divided, and the connected side is divided after inserting the carrier into the divided bottom. .

<Operation> According to the above configuration, when the cutting operation by the wire saw is completed, the isolated ground is separated from the surrounding ground, so that the processing such as crushing and unloading can be performed without affecting the surrounding ground or the existing tunnel. .

When the isolated ground is further divided into blocks, the tunnels are opened by sequentially pulling out and carrying out each block.

At this time, by laying the carrier in advance under each block, if the carrier is pulled out, the separated block can be easily pulled out.

<Example> Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

In FIG. 1, reference numeral 1 denotes an existing tunnel obtained by excavating a ground E such as a hard rock, and 2 denotes a new tunnel dug into the existing tunnel 1 by a blasting method so as to cross and open the existing tunnel 1. It is.

At the intersection of the tip of the new tunnel 2 and the existing tunnel 1, a ground (hereinafter referred to as an isolated ground) E1 made of unexcavated hard rock or the like having a distance L corresponding to the limit distance by the blasting method at the end of the construction and the existing ground The tunnel 1 is isolated by RC concrete 1a, which is a structure constituting the outer shell.

The invention is, in particular, a construction method for excavating this part.

 2 to 5 show the first embodiment.

First, along the cross-sectional shape of the new tunnel 2, a line segment is drawn on the surface of the isolated ground E1 located in front of the new tunnel 2 as shown by a chain line in FIG. Partition.

Next, by drilling the intersection between the drawn line segment and the periphery of the new tunnel 2, as shown in FIGS.
A plurality of conducting holes 3 penetrating the ground E1 and the RC concrete 1a and reaching the existing tunnel 1 are formed vertically and horizontally.

Next, the diamond wire saw 4 is inserted between a pair of nearest neighboring conductive holes 3 among the conductive holes 3, and is routed in a loop shape through the existing tunnel 1 side.

The wire saw 4 and a cutting device including the wire saw 4 are known devices for cutting hard rock and the like without vibration and without noise. One of the loops is formed in a state where the wire saw 4 is guided by the guide pulley 5 inside the new tunnel 1. The end is suspended on the tension pulley 6.

After this preparatory work, when the rotation and traction device 7 on which the tension pulley 6 is disposed is driven, the wire saw 4 is pulled in the direction of the arrow while being driven endlessly while being tensioned, and the other loop end is isolated. Approach the new tunnel 2 while cutting the ground E1.

When the other loop end of the wire saw 4 finally reaches the surface of the isolated ground E1, the cutting operation along the line connecting the adjacent conductive holes 3 is completed.

By repeating the above-mentioned cutting operation sequentially along the periphery of the new tunnel 1, the isolated ground E1 becomes as shown in FIG.
It is separated from the surrounding ground E in a three-dimensional shape almost along the inner peripheral shape of the new tunnel 2 by connecting each other (RC concrete 1a is also cut off from the surroundings along the cross-sectional shape of the new tunnel 2 even on the existing tunnel 1 side) ).

Therefore, in the subsequent processing, the inside of the separated ground E1 is crushed by, for example, a crushing method using a static crushing agent or a rock crusher, and even if the crushing is performed on the ground, the influence on the surrounding ground E, the structure of the existing tunnel 1, and Can be prevented beforehand.

In this case, more preferably, the wire saw 4 is inserted between the conductive holes 3 facing each other in the vertical direction and the horizontal direction, and when the same cutting operation as described above is repeated, finally, as shown in FIG. The inside of E1 is divided into rectangular blocks E1-1 having a cross-sectional area × L (distance of the isolated ground E1) surrounded by vertical and horizontal lines between the conductive holes 3 (the same applies to the RC concrete side) and divided. Unloading is possible.

Thereafter, by carrying out the unloading operation while pulling out each block E1-1 in order from the top by using a heavy equipment for unloading, a cavity along the cross-sectional shape of the new tunnel 2 opens to the existing tunnel 1 side, and both tunnels 1 , 2 is opened.

In each of the above steps, the traffic in the existing tunnel 1 is regulated mainly at the time of drilling the guide hole 3, when the wire saw 4 is routed to the existing tunnel 1 and at the initial cutting time, and otherwise at the time of traffic. There is no significant effect.

When the cross section of the new tunnel 2 is large or when the isolated ground E1
In the case where the distance L is long, as shown in FIG. 6, a conducting hole 3a is formed at the intersection of the vertical and horizontal line segments, and the wire saw 4 is inserted between the conducting holes 3a adjacent vertically and horizontally. A cutting operation may be performed.

FIGS. 7 and 8 show a second embodiment in which the workability of pulling out each of the divided blocks E1-1 is taken into consideration.

In the figure, a portion corresponding to the bottom of each block E1-1 is divided in advance by the wire saw 4, and a block carrier 8 is inserted into the divided portion E1-2.

The transfer table 8 is a structure made of an iron plate or the like that withstands a load and has a slippery lower surface, and has a handle 8a for a cue at a drawer end side.

In the state where the transfer table 8 is inserted, another piece including the upper side is cut lengthwise and crosswise along a line connecting the conductive holes 3a (or 3), so that the remaining three sides of the upper part and the side part are cut. The divided block E1-1 is placed on the transfer table 8.

Therefore, the block E1-1 is pulled out from the wall surface of the isolation ground E1 while being placed on the carrier 8 by pulling out the carrier 8 using the handle 8a as a clue.

In this embodiment, the cutting operation and the extraction operation of the block E1-1 cut out by the cutting operation are alternately repeated, so that the tip end of the new tunnel 2 is sequentially opened to the existing tunnel 1 side.

In the embodiment shown in FIGS. 7 and 8, it is possible to insert the carrier 8 by cutting off the bottom portion while any one of the upper and side portions of the block E1-1 is connected.

<< Effects of the Invention >> As described in detail in the above embodiments, in the tunnel connection method according to the present invention, when connecting a new tunnel to an existing tunnel, a cutting operation using a wire saw is performed while using a simple device. Along with
The excavation work for the ground that isolates the connection between the two tunnels can be easily performed without significantly affecting the surrounding ground, the structure of the existing tunnel, and traffic.

Further, by separating the isolated ground separated from the surrounding ground into blocks, each of these blocks can be divided and carried out. When the carrying out work is completed, the new tunnel is opened to the existing tunnel.

In addition, at the time of the work of pulling out the cut block, since the block can be pulled out by pulling out the carrier that is previously set on the bottom side of the block,
The work of unloading the blocks is further simplified.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing the state of the intersection of an existing tunnel and a new tunnel to which the present invention is applied, FIGS. 2 to 5 are explanatory views showing a first embodiment of the present invention, and FIG. FIGS. 7 and 8 are explanatory views showing a modification of the embodiment, and FIGS. 7 and 8 are explanatory views showing a second embodiment of the present invention. 1 ... Existing tunnel 1a ... RC concrete 2 ... New tunnel 3,3a ... Hole 4 ... Wire saw 8 ... Carrier E ... Soil E1 ... Isolated ground E1-1 ... Block E1-2 ... … Segmentation site

Claims (3)

(57) [Claims] In a final step of excavating a new tunnel dug into an existing tunnel: drilling a ground for isolating a connection between the two tunnels and forming a plurality of through holes between the tunnels; A wire saw is inserted in a loop between adjacent holes through an existing tunnel, and the wire saw is pulled in the new tunnel while being endlessly rotated while applying tension to the wire saw, so that the gap between the holes is reduced. A tunnel connection method comprising performing a cutting operation along a connecting line segment and separating the isolated ground from a surrounding ground by repeating the cutting operation. 2. After separating the isolated ground from the surrounding ground, insert the wire saw between the opposed vertical or horizontal conductive holes, and cut along the line connecting the conductive holes, 2. The tunnel connection method according to claim 1, wherein the isolation ground is divided into a plurality of blocks vertically and horizontally. 3. When the block is divided into blocks, at least one side of the block is connected, the bottom of the block is divided, and after the carrier is inserted into the divided bottom, the connection is established. 3. The tunnel connection method according to claim 2, wherein the side is divided.