JPH0941870A - Reconstruction method for tunnel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To conduct the construction work without interrupting traffic by providing a protective fence via air bags along the existing wall face, wall- cutting the outer peripheral natural ground with a gantry type excavating device, then crushing the old wall in blocks. SOLUTION: For the tunnel widening construction work, arch type steel frames 3a are installed at fixed intervals inside an existing tunnel wall 2, an outer peripheral cover 4 is provided to form a protective fence 3, and air bags 5 are inserted between the protective fence 3 and the wall 2. The outer peripheral natural ground of the existing tunnel wall 2 is wall-cut and excavated by a gantry type excavating device 7, notches are applied to the excavated portion by a concrete cutter, and the air bags are expanded to crush the concrete in blocks. The traffic in a tunnel 1 is not interrupted during the work, lining is applied to the newly excavated tunnel in sequence, and the arch steel frames 3a are removed. The tunnel widening work can be safely conducted in a short period at low cost.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is to increase lanes by expanding road widths in various places as a measure to mitigate traffic volume, which has been increasing in recent years. The demand for widening work is also high. Aside from the areas where detours can be secured during the reconstruction work of such tunnels, it is generally difficult to secure detours. In this case, widening work can be performed safely and at a low cost while securing a cross-section for vehicles and the like. It relates to a tunnel reconstruction method that was made possible.

[0002]

DISCLOSURE OF INVENTION Problems to be Solved by the Invention In the above-mentioned tunnel renovation work, a detour cannot be secured, and measures are taken to completely or temporarily block the traffic in the tunnel during the construction period. If this is not the case, it is necessary to secure a cross-section for passing vehicles, etc. in the tunnel for the entire construction period. However, the conventional method of widening tunnels of this type is parallel to the crushing of the existing lining wall (usually concrete lining). Since the ground was excavated, a large-scale H steel, etc., had to be installed in advance in the reconstructed area in the tunnel to support the rock and rocks.
The actual situation is that the installation work requires a large amount of time and enormous costs such as materials and labor.

[0003]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the prior art, the present invention is an arch-shaped steel having an effective cross-section suitable for the passage of vehicles in the existing lining wall surface of the reconstructed area in the tunnel. Protective fences that reinforce the existing lining wall by connecting frames at regular intervals and interposing an air bag, which will be described later, between the steel frame and the existing lining wall and sending a small amount of compressed air into the air bag to reinforce the existing lining wall. By the gantry type excavation device that is provided so as to be movable across the existing lining, the excavation step of cutting and widening the rock on the existing lining, and the unloading step of mechanically removing the excavation shear, and It consists of a lining process of primary and secondary lining of the widened ground, and a removal process of removing the existing lining and protective fence after the completion of the primary or secondary lining. There is provided a renovation means tunnel.

Further, in the primary lining, a concrete spraying machine equipped on the gantry or a means of using this together with a bolt setter is adopted, and when removing the existing lining wall, a concrete cutter or the like is provided on the outside of the lining wall. After making vertical and horizontal cuts at regular intervals,
A means was also used in which the existing lining was blocked and taken out by expanding the air bag.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The embodiment of the present invention will be described in more detail with reference to the drawings. An arch shape or the like is formed along the inner surface of an existing lining wall (in the case of a unearthed tunnel, its rock mass) 2 in a reconstructed area of an existing tunnel 1. Steel frames 3a are firmly connected to each other at a constant interval, the outer peripheral cover 4 covers the peripheral surface of the steel frames 3a as necessary, and the air bags 5 described later are arranged in parallel and the main hose 6 By constructing a protective fence 3 whose upper surface is in close contact with the existing lining wall surface by expanding the air cells by making it possible to distribute compressed air to each air cell 5'through this (see this figure). Fence construction process).

By the air bag 5, the existing lining wall 2 is reinforced as an integral body with no gap between it and the protective fence 3, and it is possible to prevent falling rocks and rocks due to vibration or the like during the widening work. In addition, a connecting member 3b such as a connecting bolt or a brace is provided between the steel frames 3a constituting the protective fence 3.
It can be installed firmly by providing. In the air bag of the present invention, as shown in FIG. 3, for example, a large number of connected air cells 5 ′ and 5 ′ are composed of coated polyester and other chemical fibers, and one main hose 6 The compressed air is supplied through the internal hoses 6'and 6'which branch into each air cell.

When the construction of the protective fence 3 for a certain section described above is completed, the gantry type excavation device 7 is installed so as to be able to move forward and backward across the existing lining wall 2 reinforced by the protective fence 3, and the existing lining wall is installed. Although the ground outside of 2 is excavated by cutting it to the planned size (above drilling process), depending on the ground condition, it may be excavated by a breaker mounted on the gantry or by control blasting, etc. For example, excavation will be carried out from the wellhead using the long umbrella method while improving the ground. Further, the excavated shear generated by this is carried out to the rear by means of a belt conveyor or other mechanical means using an appropriate raising machine such as a shovel loader (the carrying-out step).

Through the various steps described above, the widened bedrock is subjected to lining by using a concrete spraying machine, a bolt setter or the like (not shown) mounted on the gantry (primary). Lining process).

According to the present invention, due to the synergistic action of the protection fence 3 and the existing lining wall 2 which can be installed relatively simply by interposing the air bag 5 along the inner surface of the existing lining wall 2, the ground support function before widening is achieved. Since it is a powerful product, it is possible to greatly reduce the safety during construction and the materials and labor required for constructing protective equipment in the conventional construction method.

When the above-mentioned primary lining is completed, as a general rule, the expanded space is used to assemble the formwork, and after the secondary lining is performed, the existing lining wall 2 is demolished. Make vertical and horizontal cuts at appropriate intervals from the space on the upper surface of the existing lining wall with a concrete cutter, etc.
When the high air pressure is fed by the air bag and expanded, the existing lining wall is decomposed into a block shape, so that the destruction and carrying out work can be performed very efficiently. Therefore, the work is completed by removing the protective fence 3 after removing the existing lining wall 2.

In short, in principle, the construction method of the present invention leaves the protective fence 3 and the existing lining wall 2 until the ground excavating step for tunnel widening, the shearing-out step and the lining step are completed. The main idea is to prevent the collapse of the old ground by the above, but depending on changes in the ground conditions, the existing lining wall etc. may be partially removed before the primary or secondary lining. Even if it exists, it is merely a design modification of the method of the present invention and does not exceed the technical scope of the present invention.

[0012]

As is apparent from the above description, according to the reconstructing method of the present invention, a protective fence that can be easily installed secures an effective cross section of a vehicle or the like in a tunnel over the entire construction period. Not only that, since the existing lining is used as it is to maintain the ground level, the strength of the protective fence is doubled, and the remarkable effect that safety and cost of protective equipment can be reduced and the construction period can be drastically shortened is obtained. Be done. Therefore, according to the construction method of the present invention, it is possible to extremely shorten the time for blocking the traffic when reconstructing a tunnel, and further, by using the air bag, there is an advantage that the protective fence can be easily constructed in accordance with the cross section of the existing tunnel.

Besides, the existing lining can be crushed into blocks by an air bag, which contributes to the efficiency and safety of carrying-out work, and the speed of installation of a simple protective fence and the construction period due to repeated use, Further reduction of construction cost can be expected.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a renovated tunnel manufactured by the method of the present invention.

FIG. 2 is an enlarged sectional view taken along line XX of FIG.

FIG. 3 is a partial perspective view of an air bag.

[Explanation of symbols]

 1 Existing tunnel 2 Existing lining wall 3 Protective fence 4 Outer peripheral cover 5 Air bag 6 Main hose 7 Gantry type excavator

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshimi Tokaibayashi 3154 Ohuchi, Fuji City, Shizuoka Prefecture

Claims (2)

[Claims] 1. An arch-shaped steel frame or the like having an effective section suitable for passage of a vehicle is installed along an existing lining wall surface at regular intervals, and an air bag is interposed in parallel between the steel frame and the existing lining wall. A step of constructing a protective fence to reinforce the lining wall, an excavation step of cutting off the ground on the existing lining by a gantry type excavator provided over the existing lining wall, and a carry-out step of removing the excavation shear, A support process for lining the ground that has been further cut off,
Reconstruction method for tunnels, etc. characterized by sequentially performing the removal process of removing the existing lining wall and protective fence after the completion of the primary lining or after the completion of the secondary lining. 2. The tunnel according to claim 1, wherein upon removal of the existing lining wall, the outside of the lining is cut into vertical and horizontal cuts with a concrete cutter or the like, and then the air bag is expanded to break the existing lining wall into blocks. Reconstruction method such as.