JPH0650084A - Method for constructing multistage pipe beam - Google Patents

Abstract

PURPOSE:To enable excavation of even a long tunnel extending several hundred meters. CONSTITUTION:A first-stage pipe beam is constructed 1 and, as timbering is built into the pipe beam, excavation is carried out in the forward direction. A second-stage pipe beam 2 is constructed in front of the inside of the pipe beam 1 with an overlap at their end portions, and the inside of the pipe beam 2 is similarly excavated. Similar work is repeated as needed. Therefore, even such a long tunnel that cannot be constructed by pipe-beam construction method can safely, promptly and economically be excavated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of drilling a long tunnel by performing multi-stage pipe beam work.

[0002]

2. Description of the Related Art The pipe beam method, which is conventionally known as a method for excavating a tunnel with a thin soil cover in a place where there are houses, roads, etc. on the ground, uses a steel pipe along the outer edge of the cross section of the tunnel to be excavated. The inside of the pipe beam work that is formed by pushing them side by side is sequentially excavated forward while building the support work, but it is possible to push a large-diameter steel pipe into a predetermined position accurately. Since the limit of length is about several tens of meters, it was conventionally considered that a tunnel with a length of several hundred meters could not be constructed by the pipe beam method.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a multi-stage pipe beam construction method capable of excavating a long tunnel of several hundred meters.

[0004]

The multi-stage pipe beam construction method of the present invention is characterized in that the first stage pipe beam construction is performed from the end of the tunnel, and the inside of the pipe beam construction is carried forward in sequence while the support work is being built. To the inside of the first-stage pipe beam work, and then the second-stage pipe beam work is performed with the ends overlapping, and the inside is similarly drilled. The point is to repeat the same work in sequence.

[0005]

[Explanation of the Invention According to the Drawing] The drawing shows a long tunnel excavated from points A and B at both ends of the tunnel by the construction method of the present invention so as to communicate with each other at an intermediate portion between points A and B, and thus excavated. An example of construction for constructing an underpass W is shown inside, and in the figure, F is the ground surface.

First, vertical shafts are dug at points A and B, and steel pipes are sequentially connected horizontally in the vertical direction in which tunnels are to be excavated from the vertical shafts to form the first-stage pipe beam work 1, and the inside thereof is formed. Are sequentially excavated forward while building the support S, but the excavation method is arbitrary, and for example, the upper part of the tunnel may be excavated first.

At the stage where the excavation has proceeded to near the tip of the pipe beam work 1, a second stage pipe beam work 2 is provided inside the pipe beam work 1, and its rear end is the front end of the pipe beam work 1. They are formed so that they overlap each other.

Then, the inside of the pipe beam work 2 is excavated in the same manner as the inside of the pipe beam work 1 to advance the tunnel, and then the pipe beam work 3 of the third stage is performed in front of the inside of the pipe beam work 2, The inside is also excavated in the same way, and finally, the pipe beam work 4 of the fourth stage is performed so that the ends overlap with the insides of the pipe beam work 3 on both sides. Open the tunnel.

Since the cross section of the tunnel excavated by the method of the present invention becomes gradually smaller depending on the number of steps of the pipe beam construction to be performed, when the length of the tunnel is particularly long, as in the illustrated construction example. It is advantageous to drill from both ends of the tunnel.

[0010]

EFFECTS OF THE INVENTION Since the method of the present invention is as described above, even in a long tunnel which was conventionally impossible to be constructed by the pipe beam method, it is possible to obtain a comparative It can be constructed safely, quickly, and economically.

[Brief description of drawings]

FIG. 1 is an overall explanatory view of a construction example according to the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

3 is a cross-sectional view taken along line YY of FIG.

[Explanation of symbols]

A, B: Point, W: Underpass, F: Ground surface, S: Support work,
1, 2, 3, 4: Pipe beam work.

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[Procedure amendment]

[Submission date] June 21, 1993

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

Claims (1)

[Claims] 1. A first stage pipe beam work is performed from the end of the tunnel, and the inside is sequentially excavated forward while building a support work, and then the first stage pipe beam work is performed. The pipe beam work of the second stage is applied to the inside front so that the ends overlap, and the inside is similarly excavated,
Furthermore, the multi-stage pipe beam construction method is characterized in that the same work is repeated as needed.