JPH0428048B2 - - 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 takes advantage of the respective strengths of the open-cut construction method and the shield construction method when constructing underground structures that form water, sewage, telegraph, telephone, and other underground passages, safely and easily even in urban areas and on soft ground. It was designed to allow construction work to 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 is cut and the starting shaft 3 is cut.
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 11 using tire rollers 10 etc. as a temporary road restoration work. When the U-shaped shield machine 1 reaches the reach hole 17, it is removed and the work is completed. .

By the way, for example, as shown in FIG. 7, a concrete box 6 as a relatively large underground structure,
In order to simultaneously construct a plurality of underground structures such as humid pipes 12 as small underground structures, a U-shaped shield machine 1 having a large rectangular cross section is used.

[Problem that the invention seeks to solve]

In this way, conventionally, a large U-shaped shield machine 1
The amount of excess excavation is large due to the use of a large amount of excavation, which increases the construction period and cost. The amount of backfilling soil also increases, 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 surface and a propulsion jack is sequentially disposed behind the shield machine to excavate using a reaction force as a reaction force. The side wall or bottom plate of the mold shielding machine is partially bulged out, and the upper part of the side wall is bulged out to form an enlarged diameter part, and the bulged part forms a side groove and the enlarged diameter part forms a stepped part, respectively. The purpose is to construct a small underground structure and install a small underground structure there.

[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 and the bulge part of the side wall or bottom plate of the U-shaped shield machine, the whole shield machine does not need to be so large. Therefore, the amount of over-excavation and backfilling does not increase significantly, the concrete box and shield machine do not differ in size more than necessary, and the vertical and horizontal balance of the propulsion jack installed between them does not collapse. .

〔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 a part of one side wall 1a (near the bottom in the figure) extended outward in a rectangular shape to form a bulge 13 continuous in the length direction. .

Moreover, the upper part of the other side wall 1a is made to project outward to form an enlarged diameter part 14 that continues in the length direction.

Note that the location and number of such bulging portions 13 and enlarged diameter portions 14 are not particularly limited; for example, on both side walls 1.
An enlarged diameter portion 14 is formed at a, and a bulged portion 13 is formed below the enlarged diameter portion 14.
may be formed.

Furthermore, as another embodiment, a bulge 13 may be formed on the bottom plate 1b 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 14 as well, and the side grooves 15 are also continuously formed in the enlarged portion 13, and a shelf-like stepped portion is formed in the enlarged diameter portion 14. 16 is formed.

Therefore, it is sufficient to arrange the concrete fume pipes 12, steel pipes, etc. in the side groove 15 or on the stepped portion 16, and connect them one after another.

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. An explanatory diagram showing each process of a general example, and FIG. 7 is a front view showing a conventional example. 1...U-type shield machine, 1a...side wall, 1b...
...Bottom plate, 2...Propulsion jack, 3...Starting shaft, 4
... Earth retention, 5 ... Reaction wall, 6 ... Concrete box, 7 ... Backfill, 8 ... Backfill soil, 9 ...
Grout pump, 10... Tire roller, 11
... Road surface pavement, 12 ... Hium tube, 13 ... Bulging part, 14 ... Expanded diameter part, 15 ... Side groove, 16 ...
Step part, 17...reaching pit.

Claims (1)

[Claims] 1. In the 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 side wall or bottom plate of the U-shaped shield machine The upper part of the side wall is made to partially bulge out, and the upper part of the side wall is made to bulge out to form an enlarged diameter section.The bulge section is used to construct a side groove, and the enlarged diameter section is used to construct a stepped section at the same time. A construction method for underground structures characterized by the installation of medium-sized structures.