JPH11303065A - Execution method for diaphragm wall - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce materials and the labor of the execution of works by beforehand executing a buttress section and conducting the jointing of successive pours of the main body section of a diaphragm wall to the buttress section. SOLUTION: A diaphragm-wall construction method, in which buttresses 16 are unified in the direction crossed at right angles with a diaphragm wall body 20 and the diaphragm wall body is self-supported stably, is used as the execution method. Buttress 16 sections are excavated precedently at that time, a cage 12, to which the forming means of recesses 16a are devised, is installed at a place, where the diaphragm wall body 20 is connected, and concrete is placed. The diaphragm wall body section is excavated while the recesses 16a are formed at places, where the recess forming means of connecting sections with the buttresses 16 are considered, and concrete is placed into a groove 18 constituting the diaphragm wall body section, thus completing the diaphragm wall body section 20.

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 continuous underground wall provided with a buttress.

[0002]

2. Description of the Related Art In order to construct a continuous underground wall which is also used as a retaining wall, in order to enable the underground wall to be self-supporting without any support such as a girder at the time of root excavation, for example, a patent is used. 25th
It is known that a buttress is installed at a key point on an underground wall as disclosed in Japanese Patent No. 73413.

In this method, as shown in FIG.
A groove 1 for the retaining wall body is excavated, and a reinforcing bar for the retaining wall body whose joint portion with the buttress 2 is covered with a joint box 3 and a partition plate 4 is set in the groove 1, and then (b) ), Concrete is poured into the groove 1 except for the portion covered with the joint box 3 and the partition plate 4 to construct most of the retaining wall main body 5, and then as shown in (c). After excavating the groove 6 for the retaining wall and removing the partition plate 4, a reinforcing bar cage for the retaining wall is set in the groove,
As shown in (d), concrete is cast in the portion covered with the joint box 3 and the partition plate 4 and the groove 6 for the retaining wall to construct the retaining wall 7 integrated with the retaining wall main body 4. It is.

[0004]

However, in this construction method, since the connecting portions on both sides of the buttress are connected by the joint box 3, there is a drawback that the material and the construction work are increased.

The present invention solves the above problems,
Its purpose is to construct a buttress part in advance, and then connect the main part of the continuous underground wall to it, eliminating the need for a joint structure with a joint box and reducing the material and labor required for construction. It provides a method for building a wall.

[0006]

In order to achieve the above object, the present invention relates to a continuous underground wall construction method in which a buttress is integrated in a direction orthogonal to the underground wall main body to stably stand alone. In, the preceding buttress portion is excavated, a steel cage with a recess forming means is installed at a position where the underground wall main body is connected, concrete is poured, and then the underground wall main body is excavated, A concave portion is formed at a position where the concave portion forming means of the connecting portion with the buttress is provided, and concrete is poured to complete the underground wall main body.

As described above, in the method of the present invention, the joint box becomes unnecessary, and the buttress and the underground wall main body are joined in an uneven shape, so that the joining strength is also increased.

Further, according to the present invention, the method for forming a recess includes:
In the concrete cast into the buttress,
The recess formation position is made in a state where it has been straightened in advance, and this straightened position is made by cutting with an excavator, or made by preforming a void with a box-like iron plate, a low-strength concrete block, It is preferable to take measures such as embedding a low-strength block member such as a synthetic resin foam molding material and cutting the low-strength block member with an excavator.

[0009]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG.
(A)-(e) have shown the construction procedure by the method of this invention.

First, in the present invention, as shown in FIG.
The groove 10 to be a buttress portion is excavated in advance.

Next, as shown in FIG.
A reinforced basket 12 is built inside. Also, the shape of the rebar basket 12 is determined so as to be unstretched at a recess forming position that is a joint position with an underground wall main body portion to be described later, or
A box-shaped iron plate is erected and a void is formed in advance, or a low-strength block member 14 is arranged as shown in FIG.

As the low-strength block member 14, any material that can be easily cut by an excavator, such as low-strength concrete or synthetic resin foam, can be selected.

Next, when concrete is poured into the above-described groove 10, the buttress portion 16 is completed as shown in FIG.

Next, as shown in FIG. 3D, grooves 18 which constitute the underground wall main body perpendicular to both sides of the buttress portion 16 are formed.
Is excavated using an excavator. In the case of unreinforced concrete, or in the position where the low-strength block member 14 is disposed, the end face is excavated by an excavator in the recessed portion. When excavating unreinforced concrete, since it is young after solidification, excavation can be performed without a decrease in excavation efficiency.
Also, when the low-strength block member 14 is arranged, the cutting can be performed in the same manner. If a box-shaped iron plate is arranged, there is no need to cut the end face. In any case, after excavation of the groove 18, recesses 16a are formed on both sides of the buttress portion 16.

Thereafter, a reinforcing steel cage (not shown) is erected in the groove 18 and concrete is poured into the groove 18 to form irregularities on both sides of the buttress portion 16 as shown in FIG. And a continuous underground wall with a buttress in which the two are integrated with a predetermined joint strength can be obtained.

[0016]

As is apparent from the above description, in the method for constructing a continuous underground wall according to the present invention, the construction of the joint between the buttress and the underground wall main body can be simplified, Since the shape is uneven, sufficient bonding strength can be obtained. Further, since a joint box and a partition plate are unnecessary, materials can be saved.

[Brief description of the drawings]

1 (a) to 1 (e) are plan views showing a construction procedure of a continuous underground wall with a buttress according to the present invention.

FIGS. 2 (a) to 2 (d) are plan sectional views showing a conventional procedure for constructing a continuous underground wall with a buttress.

[Explanation of symbols]

 10, 18 groove 12 steel cage 14 low-strength block member 16 buttress portion 16a recess 20 underground wall main body

Claims (4)

[Claims] 1. A continuous underground wall construction method for integrating a buttress in a direction orthogonal to an underground wall main body and stably standing the underground wall main body independently, wherein the buttress portion is excavated in advance, and the underground wall main body portion is A reinforcing bar with a recess forming means is installed at the connecting position, concrete is poured, then the underground wall main body is excavated, and the recess forming means of the connecting portion with the buttress is taken. A method of constructing a continuous underground wall, characterized by forming a recess in the wall and casting concrete to complete the underground wall main body. 2. The recess forming method according to claim 1, wherein the recess forming position is made in advance in the concrete cast into the buttress, and the excavator cuts the unformed position. The method for constructing a continuous underground wall according to claim 1, wherein the method is performed by: 3. The method according to claim 1, wherein the method of forming the recess is performed by preforming a void using a box-shaped iron plate. 4. The method of forming a recess, wherein a low-strength block member such as a low-strength concrete block or a synthetic resin foam molding material is buried, and the low-strength block member is cut by an excavator. Item 6. The method for constructing a continuous underground wall according to Item 1.