JPH04265310A - Constructing method of underground structure - Google Patents

Abstract

PURPOSE:To decrease processes for joining sections among each element of a continuous underground wall largely, and to facilitate execution in a method, in which an underground structure composed of the continuous underground wall and an inwall brought into contact with the continuous underground wall is constructed. CONSTITUTION:A ditch hole 1a is excavated while filling joining predetermined positions among underground wall elements with a self-hardening stabilizing liquid, an a stabilizing-liquid cured wall 2a is installed to the hole section. A ditch hole 3a for the underground wall element is excavated including even one part of the stabilizing-liquid cured wall 2a, and a reinforced cylinder is built into the ditch hole 3a and concrete is placed, thus constructing a preceding element 4a.

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 the inner wall of the structure body is attached to the inner surface of a continuous underground wall serving as an earth retaining wall.

0002

[Prior Art] For example, Japanese Patent Laid-Open No. 60-85116 (E0
2D 5/18) and Special Publication No. 63-56367 (E0
Various construction methods have been developed, including 2D 5/20). Among the various inter-element joining methods, the most common method is to insert an interlocking pipe into the joint after excavation is complete, wait for the concrete to harden after pouring concrete for the preceding element, and then pull out the pipe. A groove hole for the succeeding element connected to the extracted part is excavated and concrete is poured there to construct the succeeding element.

[0003] Furthermore, various partition iron plates processed into a joint shape are welded to the ends of the reinforcing bar cage, and the reinforcing bar cage is erected after completing the excavation of the slot for the preceding element. Then, to hold down the partition iron plate, an interlocking pipe is inserted on the back side, a reaction force material made of shaped steel is inserted, or a backfilling material such as gravel or sandbags is put in. In this state, concrete for the preceding element is poured, and after the concrete hardens, the pipe, reaction material, or backfilling material is removed, and a groove hole for the succeeding element is excavated to connect to the removed portion.

0004

[Problems to be Solved by the Invention] The inter-element joining method for continuous underground walls using interlocking pipes requires a very large space on the ground side for inserting and pulling out the locking pipes, and there are problems with adjacent buildings. This may make construction extremely difficult. In addition, not only interlocking pipes but also other element-to-element joining methods that use reaction materials and backfill materials require inserting them into deep grooves and removing them again after the preceding element has hardened. The process was extremely complicated due to the repetition.

This invention was made in view of the above-mentioned conventional problems, and its purpose is to very easily connect elements without using the above-mentioned interlocking pipes, reaction materials, and backfilling materials. 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 to obtain the necessary strength as an underground structure.

[0006]

[Means for Solving the Problems] Therefore, in the present invention, an underground structure is constructed using the following procedure. ■Drill a trench while filling the joint between the elements of the continuous underground wall to be constructed with a self-hardening stabilizing liquid, harden the stabilizing liquid, and make that part a stable liquid-hardened wall. (2) Excavate a trench for the preceding element of the underground wall, including a part of the stabilized liquid-cured wall, erect a reinforcing cage there, pour concrete, and construct the preceding element. ■ Excavate a groove for the rear wall element of the underground wall, including the other part of the stabilized liquid-cured wall, erect a reinforcing cage there, and pour concrete. Build an underground wall that connects the two elements via the remaining part. ■ After repeating the above process ■■■ to construct an underground wall with a predetermined number of continuous elements, excavate the ground on one side of the continuous underground wall,
The inner wall in contact with that wall will be constructed using cast-in-place concrete.

[0007]

[Operation] When excavating the trench for the underground wall element, a part of the stabilized liquid hardened wall provided in step (2) is also excavated. The end of the element slot is then defined by a stabilized liquid-cured wall, which acts as a concrete partition during the concreting of the preceding element, similar to a conventional locking pipe. The same is true when constructing subsequent elements. However, a portion of the stabilizing liquid hardening wall remains between the preceding element and the succeeding element. Therefore, it is not as strong as a structure in which two elements are directly joined, and a continuous underground wall is constructed with the elements temporarily joined. Finally, by integrally providing an inner wall with cast-in-place concrete on the wall surface of this continuous underground wall, it is possible to construct an underground structure with sufficient strength as a whole.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 sequentially shows the steps of an embodiment of the present invention. As is well known, a continuous underground wall is constructed sequentially in units of elements of a predetermined length, but first, as shown in Figure A, self-hardening is established at the joint site of each element of the continuous underground wall to be constructed. Grooves 1a and 1b are excavated while being filled with a stabilizing liquid, and the stabilizing liquid is hardened to form stable liquid-hardened walls 2a and 2b.

Next, as shown in Figure B, a trench hole 3a for the preceding element in the underground wall is excavated. At this time, a part of the above-mentioned stabilized liquid hardening wall 2a provided at the site where the preceding element and the next element are to be joined is excavated to form the end of the slot hole 3a. A reinforcing steel cage is erected in this groove 3a, concrete is poured, and an underground wall element 4a is constructed. At this time, since the end of the slot 3a is formed by the stable liquid hardening wall 2a,
There is no need to worry about poured concrete flowing into unnecessary areas, and there is no need for conventional partition plates at the ends of the reinforcing bar cages, and locking pipes, reaction materials, and backfilling materials are used to hold down the partition plates. is also unnecessary. The work is very simple; it is sufficient to simply excavate a groove hole 3a, erect a reinforcing cage there, and pour concrete.

Next, as shown in Figure C, a slot 3b for a subsequent element connected to the element 4a is excavated. At this time, a part of the stabilized 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, a part is also provided at the planned joint with the succeeding element. A part of the stable liquid hardening wall 2b is excavated to form a groove hole 3b.
be part of. That is, one end side of the slot 3b is formed by the stable liquid hardening wall 2a, and the opposite side is formed by the stable liquid hardening wall 2b. A reinforcing steel cage is erected in this groove 3b and concrete is poured to construct the underground wall element 4b.

[0011] By repeating the above steps, a continuous underground wall with a predetermined number of continuous elements is constructed. Here, the elements 4a, 4b, 4c, ... of the underground wall are not directly connected to each other, and the stable liquid hardening walls 2a, 2b, .
...There is a remaining part. This stabilizer liquid hardening wall 2a, 2
A continuous underground wall is constructed in a state in which the elements 4a, 4b, 4c, . . . are temporarily connected via . This continuous underground wall is used as an earth retaining wall by excavating the ground on one side, and as shown in Figure D, an inner wall 5 is constructed with cast-in-place concrete in contact with the wall surface of the continuous underground wall. When constructing the inner wall 5,
At the joint between each element of the continuous underground wall (i.e., at a position corresponding to the remaining part of the stable liquid hardened walls 2a, 2b, 2c...), a columnar part 6 whose cross-sectional area is sufficiently larger than other parts is installed.
will be established. The underground wall elements 4a, 4b, 4c, ... are not directly connected to each other, and the stable liquid hardened walls 2a, 2
Since the elements are temporarily connected via b,..., the strength is inferior to that of a continuous underground wall in which the elements are directly connected, but by providing the columnar part 6 on the inner wall 5, the continuous underground wall and the inner wall can be integrated. The strength of the composite structure can be made sufficiently high.

FIG. 2 shows another embodiment of the invention. When the interval between the joint parts of the underground wall elements 4a, 4b, 4c becomes large, in order to reinforce the part of the stabilized liquid hardened walls 2a, 2b intervening in this interval part, for example, H-shaped steel 7 is used as a reinforcing material in this part. Built-in. In other words, in the step A in Fig. 1, after the groove 1a is excavated while filling with the self-hardening stabilizing liquid, but before the self-hardening stabilizing liquid is completely hardened,
An H-shaped steel is inserted into the center of the groove 1a (a position where the groove for the underground wall element is not excavated), and the stabilizing liquid is hardened in this state.

[0013]

[Effects of the Invention] In the construction method of the present invention, a groove hole is filled with a self-hardening stabilizing liquid in advance at the site where each element of a continuous underground wall is to be joined, and a wall hardened with the stabilizing liquid is installed in that area. A slot in the middle wall element is excavated, including a part of the stabilized liquid hardened wall, a reinforcing cage is erected in the slot, and concrete is poured. Therefore, since the end of the element slot is formed by the stabilized liquid hardening wall, there is no fear that poured concrete will flow out into unnecessary areas, and there is no need to provide a partition plate at the end of the reinforcing bar cage. There is no need for interlocking pipes, reaction materials, or backfill materials to hold down the material. As a result, construction of continuous underground walls becomes significantly easier than before. However, since the underground wall elements are not directly connected to each other but are temporarily connected via a stabilized liquid-cured wall, the strength is inferior to that of conventional continuous underground walls. However, since a permanent inner wall is provided in contact with the continuous underground wall, the strength of the composite structure of the continuous underground wall and the inner wall can be increased by making improvements to the inner wall. The effect that this invention makes it extremely easy to construct a continuous underground wall is a very significant effect in the overall construction work of underground structures, including internal walls.

[Brief explanation of the drawing]

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 configuration diagram of an underground structure constructed according to another embodiment of the present invention.

[Explanation of symbols]

1a, 1b Slot holes 2a, 2b at the planned joint site Stable liquid hardened walls 3a, 3b Slot holes 4a, 4b, 4 for underground wall elements
c Underground wall element 5 Inner wall 6 Column part 7 H-shaped steel (reinforcement material)

Claims (3)

[Claims] 1. A method for constructing an underground structure, which comprises constructing an underground structure consisting of a continuous underground wall and an inner wall in contact with the continuous underground wall through the following steps. ■Drill a trench while filling the joint between the elements of the continuous underground wall to be constructed with a self-hardening stabilizing liquid, harden the stabilizing liquid, and make that part a stable liquid-hardened wall. (2) Excavate a trench for the preceding element of the underground wall, including a part of the stabilized liquid-cured wall, erect a reinforcing cage there, pour concrete, and construct the preceding element. ■ Excavate a groove for the rear wall element of the underground wall, including the other part of the stabilized liquid-cured wall, erect a reinforcing cage there, and pour concrete. Build an underground wall that connects the two elements via the remaining part. ■After repeating the above steps ■■■ to construct an underground wall with a predetermined number of continuous elements, the ground on one side of the continuous underground wall is excavated, and an inner wall in contact with the wall surface is constructed using cast-in-place concrete. 2. A method for constructing an underground structure according to claim 1, wherein a reinforcing material is inserted into the groove, and the reinforcing material is built into the stabilized liquid hardening wall. 3. In step (1) of claim 1, the inner wall corresponding to the portion of the stable liquid hardening wall between the elements of the continuous underground wall is configured in a columnar shape having a larger cross-sectional area than other portions. A method of constructing a distinctive underground structure.