JP2689743B2 - How to build an underground structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of constructing an underground structure in which an inner wall of a structure body is attached to an inner surface of a continuous underground wall as a retaining wall.

[0002]

2. Description of the Related Art A method for joining elements of a continuous underground wall is described in, for example, JP-A-60-85116 (E0).
2D 5/18) and Japanese Patent Publication No. 63-56367 (E02)
Various construction methods have been developed, such as D 5/20). The most common of the various element-to-element joining methods is to insert an interlocking pipe into the joint after completion of excavation, wait for the hardening of the concrete after placing the preceding element concrete, and pull out the pipe,
The groove of the subsequent element connected to the part where this pipe is pulled out is excavated, and concrete is placed there to construct the subsequent element.

Further, various partition iron plates processed into a joint shape are welded to the end of the reinforcing bar basket, and the reinforcing bar basket is installed after the excavation of the slot for the preceding element is completed. After that, an interlocking pipe is inserted into the back surface to hold down the partition iron plate, a reaction material combined with shaped steel or the like is inserted, or a backfill material such as gravel or a sand bag is put. In that state, the concrete of the preceding element is cast, the pipe or the reaction material or the backfill material is removed after the concrete hardens, and the slot hole of the succeeding element is drilled so as to reach the removed portion.

[0004]

In the method of joining elements between continuous underground walls using interlocking pipes, a very large space is required on the ground side for inserting / pulling out the locking pipes, and it is difficult to connect with adjacent buildings. Because of this, construction may become extremely difficult. Also, not only interlocking pipes, but also other element joining methods that use reaction materials and backfill materials, insert these into deep groove holes and remove them again after concrete hardening of the preceding element. Since it was repeated, the process became very complicated.

The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to very easily connect elements between each other without using the interlocking pipe, the reaction material, and the backfill material. An object of the present invention is to provide a method for constructing an underground structure in which a continuous underground wall is constructed by joining and an inner wall is provided in contact with the wall surface so as to obtain necessary strength as an underground structure.

[0006]

Therefore, in the present invention, an underground structure is constructed by the following procedure. The site where the elements of the continuous underground wall to be constructed are to be joined is drilled while filling the self-hardening stabilizing liquid, and the stabilizing liquid is hardened to form a stable liquid hardening wall. The preceding element is constructed by excavating a slot for the preceding element of the underground wall including a part of the stable liquid hardening wall, installing a reinforced basket therein and placing concrete. A groove hole for the rear wall element of the underground wall including the other part of the stable liquid hardening wall is excavated, a reinforcing bar basket is installed therein, and concrete is placed therein, and the rest of the stable liquid hardening wall is left. Constructs an underground wall in which two elements are connected via a part. After constructing an underground wall in which a predetermined number of elements are repeated by repeating the above steps, the ground on one side of the continuous underground wall is excavated, the inner wall in contact with the wall is constructed by cast-in-place concrete, and the continuous underground Said between the wall elements
The inner wall corresponding to the part of the stable liquid hardening wall is different from the other part.
The columnar shape has a large cross-sectional area .

[0007]

When the trench hole for the underground wall element is excavated, a part of the stabilizing liquid hardening wall provided in the step is also excavated. Then, the end of the element slot is formed by the stable liquid hardening wall, and this functions as a partitioning member for concrete when pouring concrete of the preceding element, similarly to the conventional rocking pipe. The same is true when constructing subsequent elements. However the prior element during a subsequent element portion of the stabilizing solution hardening wall is left.
Therefore, it is not enough in strength than the one that directly joins two elements, so to speak, a continuous underground wall is constructed with the elements temporarily joined, but in the end, this continuous underground wall An inner wall is integrally formed by cast-in-place concrete on the wall, and its preceding element and subsequent element
The inner wall of the part temporarily joined with
Since it has a large columnar shape, it is possible to construct an underground structure having sufficient strength as a whole.

[0008]

FIG. 1 shows the steps of one embodiment of the present invention in order. As is well known, the continuous underground wall is constructed in sequence for each element of a predetermined length, but first, as shown in Fig. A, the self-hardening property is set at the planned joining site of each element of the continuous underground wall to be constructed. The groove holes 1a and 1b are excavated while filling the stabilizing solution, and the stabilizing solution is cured to form the stabilizing solution hardening walls 2a and 2b.

Next, as shown in FIG. B, the slot 3a for the preceding element of the underground wall is excavated. At that time, a part of the above-mentioned stabilizing solution hardening wall 2a provided at the joining site between the preceding element and the next element is excavated to form the end of the groove hole 3a. A reinforced steel basket is built in this slot 3a and concrete is poured to construct the underground wall element 4a. At this time, since the end of the groove hole 3a is formed by the stable liquid hardening wall 2a, there is no concern that the poured concrete will flow out to an unnecessary portion, and the end of the reinforcing bar basket has no conventional partition plate. It is unnecessary, and neither locking pipes nor reaction materials or backfilling materials for pressing the partition plate are necessary. Simply slot 3
All that is required is to excavate a, build a reinforced basket in it, and place concrete in it, and the work is very simple.

Next, as shown in FIG. C, a slot 3b for a succeeding element connected to the element 4a is excavated. At this time, part of the stable liquid hardening wall 2a at the joint with the preceding element 4a is also excavated to form a part of the groove hole 3b, and on the opposite side, it is further provided at the planned joining site with the succeeding element. A part of the stabilizing liquid hardening wall 2b is excavated to form a groove hole 3b.
Part of That is, one end of the groove 3b is formed by the stable liquid hardening wall 2a, and the opposite side is formed by the stable liquid hardening wall 2b. A reinforced steel basket is built in the slot 3b and concrete is poured to construct the underground wall element 4b.

By repeating the above steps, a continuous underground wall in which a predetermined number of elements are continuous is constructed. Here, the elements 4a, 4b, 4c, ... Of the underground wall are not directly joined to each other, and the stabilizing liquid hardening walls 2a, 2b,
... there are some intervening parts. The stabilizing solution hardening walls 2a, 2
A continuous underground wall is constructed with the elements 4a, 4b, 4c, ... The ground on one side is excavated by using the continuous underground wall as a retaining wall, and as shown in FIG. D, the inner wall 5 is constructed by cast-in-place concrete while being in contact with the wall surface of the continuous underground wall. When building the inner wall 5,
A columnar portion 6 having a cross-sectional area sufficiently larger than the other portions at the joint portion between the elements of the continuous underground wall (that is, the position corresponding to the remaining portion of the stable liquid hardening walls 2a, 2b, 2c ...).
Is provided. The underground wall elements 4a, 4b, 4c, ... Are not directly joined to each other, and the stable liquid hardening walls 2a, 2
It is inferior in strength as compared with the continuous underground wall where the elements are directly joined because it is temporarily connected via b, ..., but by providing the inner wall 5 with the columnar portion 6, the continuous underground wall and the inner wall are integrated. The strength of the composite structure can be sufficiently increased.

FIG. 2 shows another embodiment of the present invention.
When the space between the joints of the underground wall elements 4a, 4b, 4c becomes large, in order to reinforce the portions of the stable liquid hardening walls 2a, 2b interposed in the space portions, for example, H-shaped steel 7 Built in. That is, in the process of A in FIG. 1, after the self-hardening stabilizing solution is filled with the self-hardening stabilizing solution, the groove 1a is drilled, and before the self-hardening stabilizing solution is completely cured,
The H-section steel is inserted into the central portion of the slot 1a (the position where the slot for the underground wall element is not excavated), and the stabilizing solution is hardened in that state.

[0013]

According to the construction method of the present invention, a groove is excavated while preliminarily filling a self-hardening stabilizing liquid in a planned joining site between elements of a continuous underground wall, and a stabilizing liquid hardening wall is provided at that portion, and then the underground is formed. The groove hole of the wall element is excavated including a part of the stable liquid hardening wall, the reinforcing bar basket is installed in the groove hole, and concrete is placed to form a continuous underground wall.
The inner wall is integrated with the underground wall by using cast-in-place concrete
Provided between the preceding element and the succeeding element.
The inner wall of the joined part has a larger cross-sectional area than other parts
It has a columnar shape. Therefore, since the end of the element groove hole is formed by the stable liquid hardening wall, there is no fear of pouring concrete flowing out to unnecessary parts, and there is no need to provide a partition plate at the end of the reinforcing bar basket, and thus the partition plate No interlocking pipes, reaction materials or backfilling materials are needed to hold down , and as a result the construction of continuous underground walls is significantly easier than in the past. Then, the part where the underground wall elements are not directly joined but temporarily joined through the stable liquid hardening wall is in contact with the element.
The inner wall of the installation has a columnar shape with a larger cross-sectional area than other parts.
Therefore, the strength as a composite structure of the continuous underground wall and the inner wall is sufficient.

[Brief description of the drawings]

FIG. 1 is a process diagram of a method for constructing an underground structure according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of an underground structure constructed according to another embodiment of the present invention.

[Explanation of symbols]

 1a, 1b Grooves for planned joining 2a, 2b Stabilizing liquid hardening walls 3a, 3b Grooves for underground wall element 4a, 4b, 4c Underground wall element 5 Inner wall 6 Columnar portion 7 H-shaped steel (reinforcing material)

Claims (1)

(57) [Claims] 1. A method for constructing an underground structure, which comprises constructing an underground structure comprising a continuous underground wall and an inner wall in contact with the continuous underground wall by the following steps. The site where the elements of the continuous underground wall to be constructed are to be joined is drilled while filling the self-hardening stabilizing liquid, and the stabilizing liquid is hardened to form a stable liquid hardening wall. The preceding element is constructed by excavating a slot for the preceding element of the underground wall including a part of the stable liquid hardening wall, installing a reinforced basket therein and placing concrete. A groove hole for the rear wall element of the underground wall including the other part of the stable liquid hardening wall is excavated, a reinforcing bar basket is installed therein, and concrete is placed therein, and the rest of the stable liquid hardening wall is left. Constructs an underground wall in which two elements are connected via a part. After constructing an underground wall in which a predetermined number of elements are repeated by repeating the above steps, the ground on one side of the continuous underground wall is excavated, the inner wall in contact with the wall is constructed by cast-in-place concrete, and the continuous underground Said between the wall elements
The inner wall corresponding to the part of the stable liquid hardening wall is different from the other part.
The columnar shape has a large cross-sectional area.