JPH0428047B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an open shield construction method among construction methods for underground structures.

[Conventional technology]

The open shield construction method is a method for constructing underground structures that form underground passages for water, sewage, telegraph, telephone, and other underground passages.It takes advantage of the respective strengths of the open-cut construction method and the shield construction method, and can be used safely and easily even in urban areas and on soft ground. It was designed so that construction work could be carried out.

First, let's look at a general example of this open shield method in Part 3.
To explain each process with respect to FIGS. 3 to 6, first, as shown in FIG. The earth retaining hole 4 was cut and the starting hole 3 was opened.
The propulsion jack 2 is extended by using the reaction wall 5 formed therein as a reaction force to make it dig into the ground. During the excavation, the earth and sand will be discharged using a shovel such as a excavator 7, an auger, etc.

Next, a concrete box 6, etc. is suspended from the ground to the tail of the U-type shield machine 1 (see Figure 5), and the concrete box 6 is used as a reaction force to further extend the U
Type shield machine 1 is made to dig.

After a plurality of concrete boxes 6 are arranged in tandem in this manner, backfilling soil 8 is applied to the upper surface thereof, and the area around the boxes 6 is grouted using a ground pump 9.

This process is repeated, and if necessary, the road surface is paved with tire rollers 10, etc. as temporary road restoration work, and when the U-shaped shield machine 1 reaches the reach hole 15, it is removed and the work is completed. .

By the way, as shown in FIGS. 7 and 8, for example, a plurality of underground structures, such as a concrete box 6 as a relatively large underground structure and a Huyum pipe 12 as a small underground structure, can be installed at the same time. For the construction, a U-shaped shield machine 1 with a large rectangular cross section is used.

[Problem that the invention seeks to solve]

Figure 7 shows the case where the hume pipe 12 is installed on one side of the concrete box 6, and Figure 8 shows the case where the hume pipe 12 is installed on both sides of the box 6, but in both cases, a large U-shaped shield is used. Since machine 1 is used, the amount of excess excavation becomes large, increasing the construction period and construction cost. and,
The amount of backfilling soil will also increase, further increasing the construction period and cost.

Furthermore, as mentioned above, the U-type shield machine 1 excavates using the concrete box 6 as a reaction force, and since the concrete box 6 has a smaller cross section than the shield machine 1, the box 6 and the shield machine 1
The arrangement of the propulsion jacks in between will result in an imbalance in the vertical and horizontal directions. As a result, the direction of excavation is likely to be deviated.

The purpose of the present invention is to eliminate the disadvantages of the conventional example,
Even when constructing multiple underground structures at the same time, by excavating only the necessary areas as much as possible, we can prevent an increase in the amount of excess excavation and backfilling when excavating with a shield machine, and reduce the construction period.
It is an object of the present invention to provide a construction method for an underground structure that can reduce construction costs and provide good directionality during excavation.

[Means for solving problems]

In order to achieve the above object, the present invention provides an open shield construction method in which a U-shaped shield machine with an open top and a propulsion jack is sequentially disposed behind the shield machine to excavate using a reaction force as a reaction force. The gist of this method is to extend the upper part of the side wall of the mold shield machine to form an enlarged diameter section, and to continuously form a stepped section for arranging a small underground structure in the enlarged diameter section.

[Effect]

According to the present invention, when simultaneously constructing a large concrete box and a small underground structure such as a humid pipe,
Since the small underground structure is installed using the enlarged diameter part of the upper part of the side wall of the U-shaped shield machine, the entire shield machine does not need to be so large. Therefore, the amount of over-excavation and backfilling does not increase significantly, and the size of the concrete box and shielding machine do not differ more than necessary.
The vertical and horizontal balance of the propulsion jack installed between the two remains unchanged.

〔Example〕

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

Figure 1 is a front view showing one embodiment of the underground structure construction method of the present invention, and 1 in the figure is for the open shield construction method, with the top surface open and a propulsion jack (not shown) installed inside or at the rear end. ) U-type shield machine 1
shows.

The U-shaped shield machine 1 used in the construction method of the present invention has the upper part of one side wall 1a extended outward,
An enlarged diameter portion 13 that is continuous in the length direction is formed.

As another embodiment, the enlarged diameter portions 13 may be formed on both the left and right sides by projecting the upper portions of both side walls 1a, 1a of the shield machine 1 outward, as shown in FIG.

Next, the construction method of the present invention using such a U-shaped shield machine 1 will be explained.

Regarding the entire open shield construction method, please refer to Section 3 above.
This is as explained in Figures to Figure 6, and the concrete box 6 is sequentially arranged behind the U-type shield machine 1, and the shield machine 1 is moved forward using this as a reaction force, so the detailed explanation is omitted. do.

Naturally, the U-shaped shield machine 1 excavates the enlarged diameter portion 13 as well, and forms a shelf-like stepped portion 14 that continues in the advancing direction at the enlarged diameter portion 13. Discharge of earth and sand from this enlarged diameter portion 13 is no different from other parts, and can be easily performed.

Then, concrete fume pipes 12, steel pipes, etc. may be arranged on the horizontal floor of the stepped portion 14, and these may be successively connected.

In this way, the concrete box 6 and the humid pipe 12 can be placed at the same time, and backfilling can be done as appropriate.

〔Effect of the invention〕

As described above, in the construction of the underground structure of the present invention, a U-shaped shield machine with an open top and a propulsion jack is sequentially disposed behind the shield machine, and the concrete box is used as a reaction force to excavate. In the open shield construction method, when constructing a concrete box and a small underground structure such as a humid pipe at the same time,
Since a shield machine that is uniformly large throughout is not used, there is less need for over-digging, and the amount of backfilling soil can also be reduced. As a result, the construction period can be significantly shortened and costs can be reduced.

Furthermore, since the difference in cross-sectional size between the shield machine and the concrete box is not that large, the placement of the propulsion jacks between them will not be unbalanced vertically or horizontally, and the concrete box will be used as a reaction force to propel the vehicle. When pushing out the shield machine while extending the jack, there is less risk of the direction going out of order, making it highly reliable.

[Brief explanation of drawings]

Fig. 1 is a front view showing the first embodiment of the construction method for underground structures of the present invention, Fig. 2 is a front view showing the second embodiment of the same as above, and Figs. 3 to 6 are the open shield construction method. Explanatory diagrams showing each process of a general example, Figures 7 and 8
Each figure is a front view showing a conventional example. 1...U-type shield machine, 1a...side wall, 2...
Propulsion jack, 3... Starting pit, 4... Earth retention, 5...
... Reaction wall, 6 ... Concrete box, 7 ... Backfill, 8 ... Backfill soil, 9 ... Grand pump, 10 ... Tire roller, 11 ... Road surface pavement, 12 ... Huyum pipe, 13 ... ... Expanded diameter part, 14
...Step part, 15...Achievement pit.

Claims (1)

[Claims] 1. In an open shield construction method in which a U-shaped shield machine with an open top and a propulsion jack is used as a reaction force to excavate concrete boxes sequentially arranged behind the shield machine, the upper side wall of the U-shaped shield machine 1. A method for constructing an underground structure, characterized by forming an enlarged diameter part by overhanging the diameter part, and continuously forming a stepped part for arranging a small underground structure in the enlarged diameter part.