JP2000230389A - Construction of tunnel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tunnel construction method wherewith a period of time required for blocking general traffic can be reduced and noises arising from excavation of the tunnel hardly reach the ground surface. SOLUTION: With this tunnel construction method, two lines of vertical shafts 12, 14 being in parallel with each other are formed. A plurality of refrigerant circulating pipes 20, 22 crossing each other and extending downward respectively from each of the vertical shafts and a refrigerant circulating pipe 24 extending horizontally from one of both of the vertical shafts are arranged in the ground. With a refrigerant made to circulate through the pipes, a pair of opposite side walls 28, 30 and a top wall 32 connecting with both of the side walls each comprising of frozen soil are formed. Then, the ground enclosed with these walls is excavated. The excavation may be executed by an inverted lining method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing a tunnel, and more particularly to a method for constructing a tunnel having a large cross-sectional area, such as a motorway tunnel.

[0002]

2. Description of the Related Art Conventionally, in order to construct a large-section tunnel, a pair of continuous underground walls opposed to each other are constructed and used as earth retaining walls, and then a ground portion between the earth retaining walls is cut. ing.

According to this, in order to avoid as much as possible the interruption of general traffic associated with the construction of a tunnel, the digging space is covered with a lining plate during digging.

[0004] However, the construction of the continuous wall requires a relatively long period of interruption of general traffic, and noise during the excavation work leaks to the ground through the lining plate, thereby deteriorating the environment in the city area. There was a problem.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a tunnel construction method for shortening a period of interruption of general traffic. Another object of the present invention is to provide a tunnel construction method in which noise during tunnel excavation hardly leaks to the ground.

[0006]

According to the present invention, there is provided a tunnel construction method comprising: forming two parallel shafts;
Crossing each other, a plurality of refrigerant circulation tubes extending downward from each shaft and a plurality of refrigerant circulation tubes extending horizontally from one of the shafts are installed in the ground, and the refrigerant is circulated in the tubes, This includes forming a pair of opposing side walls and both side walls made of frozen soil and excavating the ground surrounded by these walls.
Ground excavation can be performed using a reverse winding method.

[0007]

According to the present invention, a ground portion surrounded by a pair of side walls and a top wall formed by freezing a part of the ground in the ground is excavated. It is possible to construct a tunnel in a state where leakage is difficult.
Further, the supply of the refrigerant to the refrigerant circulation pipes installed in the ground to form the side walls and the top wall is performed by lining a double-pitted shaft that is cut and opened to install these pipes in the ground. This can be done while covering with a board. For this reason, it is possible to shorten the period in which the shaft is kept open, that is, the period in which general traffic is cut off.

[0008]

DETAILED DESCRIPTION OF THE INVENTION Referring to FIG. 1, a tunnel having a rectangular cross-sectional shape and constructed in accordance with the present invention is indicated generally by the numeral 10. The tunnel 10 has, for example, a cross section large enough to pass through a highway.

To construct the tunnel 10, first, the ground 1
1 is cut to form two vertical shafts 12, 14 parallel to each other.

[0010] The length of the double shafts 12, 14 is the length of the tunnel 1.
Equivalent to a planned construction length of 0.

One of the two vertical shafts 12 has two parts. That is, the shaft portion 16 having a shallow depth
And a shaft section 18 having a greater depth connected to the shaft section.

On the other hand, the other shaft 14 has the same depth and width as the shallow shaft portion 16 of one shaft 12, and is opposed to the shaft portion 16. Thus, the deep shaft portion 18 is located on the opposite side of the shaft 14 rather than the shaft 14 with respect to the shallow shaft portion 16.

After the formation of the shafts 12, 14, a plurality of refrigerant circulation tubes 20, 22 extending vertically downward from the shaft shaft portion 16 and the shaft shaft 14, and from the shaft shaft portion 18 to the side of the shaft shaft 14. A plurality of refrigerant circulation tubes 24 extending horizontally
Is installed in the ground 11.

Each of the tubes 20, 22, 24 is, for example, a double tube having two openings. Therefore, the refrigerant can be supplied from one opening of the double pipe and recovered from another opening, and can be circulated in the double pipe during this time. Underground water around the double pipe may be frozen during the circulation of the refrigerant. As the refrigerant, for example, calcium chloride can be used.

The operation of supplying and recovering the refrigerant can be performed in each of the shafts 12 and 14.
During this time, the shafts 12, 14 can be covered with a lining plate (not shown) made of a steel plate. Therefore, except for the relatively short period required for excavation of both shafts 12,14,
The ground surface can be used for general traffic for a relatively long period of time required for tunnel construction.

Prior to installation of the plurality of tubes, a plurality of elongated holes for inserting the plurality of tubes are provided in the ground at an interval from each other. That is, shallow shaft part 1
A plurality of elongated holes extending vertically from 6 (not shown)
And a plurality of elongated holes (not shown) extending vertically downward from the other shafts 14, and furthermore, a deep shaft portion 1
A plurality of elongated holes (not shown) extending horizontally from 8 to the side of the shaft 14 are provided.

The vertical hole and the horizontal hole correspond to the shaft 1
A boring machine (not shown) is carried into the pits 2 and 14, and is operated in the pit, thereby forming the ground 1.
1 can be drilled.

Thereafter, the pipes 20, 22 and 24 are inserted into the vertical holes and the horizontal holes from the shafts 12 and 14, respectively, and installed underground.

The plurality of holes extending vertically from the shallow shaft portion 16 and the shaft 14, respectively, are spaced from each other in the direction of extension of the shaft.

The plurality of holes extending horizontally from the deep shaft portion 18, more specifically, from a position deeper than the shallow shaft portion 16 and the shaft 14 in the shaft portion 18, also extend in the extending direction of the shaft. Are spaced apart from each other. Moreover, these horizontal holes extend between the vertical holes, and thus intersect at right angles with the vertical holes.

Therefore, the plurality of tubes 24 extending through the plurality of horizontal holes extend between the plurality of tubes 20 extending through the plurality of vertical holes and the plurality of tubes 22 respectively. 24 and each of the tubes 20, 22 are orthogonal to one another.

For this reason, by the circulation of the refrigerant in the pipe, as shown by reference numeral 26 in FIG. 1, a wall having a gate-shaped cross-sectional shape that continuously extends in the extending direction of the shaft, ie, a vertical wall A pair of opposing side walls 28 and 30 made of frozen soil around the plurality of tubes 20 and 22 and a top wall 32 connected to both side walls 28 and 30 made of frozen soil around the plurality of horizontal tubes are underground. Formed.

Thereafter, in order to construct the tunnel, a pair of shafts 3 are provided at both ends of the portal wall 26 in the extending direction.
4, 36, and excavates the ground surrounded by the portal wall 26 made of frozen soil from inside one shaft 34 to the other shaft 36 using a drilling device such as a backhoe. .

Since the excavation work is performed in the ground surrounded by the wall 26 of the gate 26, the noise accompanying the excavation hardly leaks to the ground. Also, during excavation work, most of each shaft 34, 36 can be covered with a lining plate (not shown) similar to that described above, thereby reducing leakage of the noise to the ground. In addition, obstacles to general traffic on the ground surface can be reduced.

Excavation can be performed using a reverse winding method, as shown in FIGS. However, in FIGS. 2 and 3, the walls 28, 30, and 32 made of frozen soil are omitted to clarify the excavation situation.

In this construction method, first, a part below the top wall 32 is excavated over substantially the entire length of the top wall 32, and then is spaced apart from each other in the longitudinal direction of the top wall 32. Are arranged along the excavated wall surface.

Next, a movable formwork 40 that curves along the steel supporter 38 is disposed below the steel supporter 38, and concrete is cast between the steel supporter 38 and the formwork 40. This is repeated from the side of one shaft 34 to the side of the other shaft 36 to form the upper slab concrete 42.

Next, the underside of the upper slab concrete 42 is excavated to form a large back 44, a horizon, a middle split, and the like. Then, a plurality of side walls 46 and a middle wall 48 (FIG. 1) made of cast concrete are constructed.

During or after the formation of the large back 44, the horizon, the middle split, etc., the construction of the side walls 46 and the middle wall 48, the height of the lower end of the lower side of the two side walls 28, 30 made of frozen soil, From the height position to the upper height position (for example, a height position several meters above), the formation of the large back 50, the horizon, the middle split, and the like, the construction of the side walls and the middle wall, and the like are repeated.

In this way, a tunnel 10 having a rectangular cross-sectional shape as a whole, which is made of a cast concrete compact, is constructed. The illustrated tunnel 10 is divided into four internal spaces.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a tunnel constructed in accordance with the present invention.

FIG. 2 is a longitudinal sectional view of a tunnel under construction.

FIG. 3 is a partial cross-sectional view of a tunnel under construction as viewed from above.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Tunnel 12,14 Two-row shaft 20,22 Vertical refrigerant circulation pipe 24 Horizontal refrigerant circulation pipe 28,30 Side wall made of frozen soil 32 Top wall made of frozen soil

Claims (2)

[Claims] 1. Forming two parallel vertical shafts, a plurality of refrigerant circulation tubes crossing each other and extending downward from each vertical shaft, and a plurality of refrigerant circulation tubes extending horizontally from one of the vertical shafts. Installing the pipe in the ground, circulating a refrigerant in the pipe, thereby forming a pair of opposing side walls made of frozen soil and a top wall connected to both side walls, the ground surrounded by these walls A method of constructing a tunnel, including excavating. 2. The method according to claim 1, wherein excavation of the ground surrounded by the wall is performed using a reverse winding method.