JP3434011B2 - Wall construction method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wall construction method for constructing an underground wall.

[0002]

2. Description of the Related Art As is well known, the prestressing method is widely used because it has an advantage that the wall thickness can be reduced by applying prestress to concrete.

Further, when starting a shield machine from a vertical shaft or reaching a shield machine to a vertical shaft, conventionally, a ground improvement such as a chemical injection work is performed on the earth retaining wall of the vertical shaft on the outside of the starting or arriving entrance of the shield machine. The ground improvement section was created by the construction method, and the pit mouth of the retaining wall was manually demolished.

[0004]

Here, in the conventional connecting wall construction method, reinforcing bar cages (cages) are sequentially built in the connecting wall grooves, and the vertical bars of the upper and lower reinforcing bar cages are connected and integrated. Therefore, in the conventional construction method, even if the longitudinal muscles are strained, elongation occurs at the connecting portion and prestress cannot be applied.

In the conventional method, there is a problem that it is necessary to construct a ground improvement portion by a ground improvement method such as a chemical injection method, and the manual removal of the well is dangerous.

The present invention has been proposed in view of the above-mentioned prior art, and it is possible to carry out the prestressing method, and to start and reach the shield machine without the need for ground improvement or manual destruction of the well. The purpose is to provide the wall construction method.

[0007]

According to the continuous wall construction method of the present invention, a continuous wall groove excavating step and a cage building step of building a cage in the continuous wall groove are included. The built-in cage is constructed by connecting vertical strips suspended from each of a pair of reels with horizontal strips and spacing strips.
The longitudinal strip is made of a material having tensile strength and flexibility, and a predetermined portion is made of a material having tensile strength and flexibility and the property of being easily cut. The strip material and the space keeping strip material are made of the same material as the longitudinal strip material in the connected place, and the soil cement concrete is placed in the lower part of the wall groove in which the cage is built. A step, a tensioning step for tensioning the vertical strip after solidification of the root-consolidating concrete, a concrete placing step for placing concrete, and a tension release for the vertical strip after solidification of the cast concrete. Including the tension release step of applying pre-stress, the strip material of the new material and the longitudinal strip material are connected by a coupler, and the coupler embeds both strip materials in the mounting steel pipe containing the strip material and the steel pipe Non-shrink concrete Is configured, the coupler is surrounded by Kapurashisu, in the interior of the Kapurashisu grease is filled.

Further, according to the present invention, it includes a continuous wall groove excavating step and a cage building step of building a cage in the continuous wall groove, and a pair of cages are built in the building step. Vertical strips suspended from each of the reels are connected by a horizontal strip and a spacing strip, and the vertical strips are made of a material having tensile strength and flexibility and have a predetermined length. The points are made of a material having tensile strength and flexibility and the property of being easily cut, and the transverse strips and the spacing strips are the same material as the longitudinal strips at the connecting points. And a step of placing concrete into the lower part of the continuous wall groove in which the cage is built,
A concrete placing step of placing concrete after solidifying the root-consolidating concrete, a tensioning step of tensioning the longitudinal strip before the placed concrete is completely solidified, and A tension release step of releasing the tension of the longitudinal strip to give a pre-stress, and the strip of new material and the longitudinal strip are connected by a coupler, and the coupler is a mounting steel pipe containing both strips And non-shrinkable concrete in which both strips are embedded in the steel pipe, the coupler is surrounded by a coupler sheath, and the inside of the coupler sheath is filled with grease.

[0009]

[0010]

[0011]

According to the continuous wall construction method of the present invention having the above-mentioned structure, a pair of vertical strips hung from a reel are connected by a horizontal strip and a spacing strip. The cage is built in, and the continuous longitudinal strips constituting the cage are tensioned (tensile force is applied) to give tension.
Then, after the concrete is solidified, the tension (tensile force) applied to the longitudinal strips is released to give prestress to the solidified concrete (concrete that has been placed in the cage construction site). be able to.

Here, in the present invention, a predetermined portion of the built-in cage, that is, a wellhead portion, is composed of a strip material made of a material having tensile strength and flexibility and the property of being easily cut. Has been done. Therefore, if the concrete to be placed at the predetermined location is concrete using coarse aggregate of limestone (aggregate of lightweight aggregate concrete), both the strip material and the concrete are easily excavated by the cutter bit of the shield machine. The shield machine can easily penetrate the predetermined place.

On the other hand, since the tensile strength of the wellhead portion is reinforced by the strip material made of the new material, the strength of the structure constructed in the ground does not become poor.

The step of assembling the cage is carried out by the same method as in Japanese Patent Application No. 6-5534 previously filed by the present applicant. That is, the tensile strength of the reel wound around the pair of through holes of the spacers stacked and housed in the spacer holder facing the opening of the communicating wall groove and connected to each other at a predetermined interval by the high tension wire is sufficient. A preparatory step of inserting a strip having flexibility and fixing the lower end of the strip to the lowermost spacer, and rotating the reel to feed the strip to lower the lowest spacer. The lowermost spacer lowering step, the spacer lowering step of sequentially lowering the upper spacer by lowering the lowermost spacer, and when the strip reaches the bottom of the connecting wall groove, the top of the strip and the top By the strip material fixing step of fixing the spacer and the spacer, the cage is built in the connecting wall groove.

According to this method, when the lowermost spacer is lowered, the upper spacers are sequentially pulled out by the high tension wire, and the cage is assembled by the double pairs of strips and the plurality of spacers. Then, when concrete is placed in the continuous wall groove in which the cage is formed, the spacers other than the lowest spacer are held at predetermined intervals by the high tension wire against the pushing force of the placed concrete.

[0016]

Embodiments of the first construction method will be described below with reference to the drawings.

(1) Connecting Wall Groove Excavation Process The connecting wall groove 1 (FIG. 1) is excavated by an unillustrated connecting wall excavator.

(2) Cage-building step (FIG. 1) 1 on both sides of the opening 2 of the continuous wall groove 1 filled with the stabilizing solution 3
Position the pair of reels 4, 4. A plurality of vertical strips 6 are wound around the reel 4, and the vertical strips 6 are wound around the reel 4.
And the lateral strip 7 and the spacing member constitute a cage A. Here, the vertical strip 6, the horizontal strip 7 and the spacing member are made of a material having tensile strength and flexibility, for example, PC steel wire.

At the time of building the cage, the reels 4 and 4 are rotated in the direction of the arrow a to suspend the strip 6 and the lateral strip 7 and the spacing member in the connecting wall groove 1, and the cage will be described later. Build body A.

Further, a predetermined portion of the cage A, that is, a predetermined portion S1 including a portion corresponding to a circular wellhead S as shown in FIG. 2 is made of a new material such as carbon fiber having flexibility and cutting property. It is composed of a vertical strip 6a, a horizontal strip 7a and a spacing strip 8a. Then, as shown in FIG. 3, for example, both longitudinal strips 6 and 6a are connected by a coupler 10. The coupler 10 is composed of a mounting steel pipe 11 and a non-shrinkable concrete 12 filled therein. The mounting steel pipe 11 accommodates the strips 6 and 6a with a gap therebetween, and the non-shrinkable concrete 12 and the inner wall surface of the mounting steel pipe 11 meet both conditions 6, 6.
It is filled in the gap between a and a, and both strips 6 and 6a are embedded and connected. This coupler 10 is a coupler sheath 2
0, and the inside of the coupler sheath 20 is filled with grease 13.

(3) Rooting concrete placing step (FIG. 2) Rooting concrete 14 is placed below the longitudinal strip 6.

(4) Tensioning step After placing the concrete for consolidating the concrete 14, the reels 4 and 4 are rotated in the direction of arrow b to extend the longitudinal strip 6 to apply tension. However, a tension applying means (not shown) may be separately installed to apply tension to the longitudinal strip 6.

(5) Concrete placing step (FIG. 2) With a tremie pipe (not shown), a lightweight aggregate (for example, coarse limestone aggregate) is provided in the depth level range S2 including the predetermined location S1.
Concrete is cast, and ordinary concrete is cast in the level range other than the range S2.

(6) Tension release step (FIG. 2) After the concrete is solidified, the reels 4 and 4 are rotated in the direction of arrow a to release the tension of the longitudinal strip 6 to apply prestress. (Not shown tension applying means,
For example, when the tension is disabled by a jack or the like, the means may be operated so as to remove the tension. ) Therefore, the area S2 can be easily excavated by the cutter bit of the shield machine and the wellhead S can be demolished.

Next, an embodiment of the second construction method will be described.

(1) Connecting wall trench excavation step (2) Cage building step (3) Rooting concrete placing step (4) Concrete placing step The steps (1) to (4) above are the first step. It is the same as the construction method.

(5) Tensioning Step While the cast concrete is not completely solidified, the reels 4 and 4 are rotated in the direction of arrow b to apply tension to the longitudinal strip 6.

(6) Tension release step This is the same as the first construction method.

Here, the cage building step is performed in the same manner as in Japanese Patent Application No. 6-5534 filed by the applicant of the present invention. That is, as shown in FIG. 4, above the opening of the communicating wall groove 1, a spacer holder 101 having an upper and lower opening slightly smaller than the opening is installed by means not shown. Spacers 110 are stacked and housed inside the spacer holder 101, and the four corners of the spacers 110 are connected to each other at predetermined intervals C by high tension wires (for example, Tegs) 102. Then, the longitudinal strip 6 wound around the reel 4 (FIG. 1) is inserted through the multiple pairs of through holes 114 formed in the spacer 110.

When assembling the cage A with the structure shown in FIG. 4, first, as a preparatory step, a plurality of strips 6, 6 wound around the reel 4 are stored in the spacer holder 101. Of spacers 110, 110 ...
14 through which the lower end is the lowest spacer (not shown)
Fasten by any means. Then, the reels 4, 4 are rotated in the direction of the arrow a (FIG. 1) by means not shown, and the strips 6, 6, ... Are fed out to lower the lowest spacer.

When the strips 6 and 6 are further extended and the lowermost spacer descends, the upper spacers are sequentially pulled down from the spacer holder 101 by the four high tension wires 102. When the lower ends of the strips 6, 6 ... Have reached the bottom of the connecting wall groove 1, the tops of the strips 6, 6 and the uppermost spacer 1
10Z (the uppermost spacer in the spacer holder 101 in FIG. 4 is referred to as the uppermost spacer 110Z for explanation)
And are fixed by a known cone-shaped wedge 109, and a cage indicated by reference numeral A is assembled. Concrete is poured into the connecting wall groove 1 in which the cage A is assembled to form a connecting wall.

At the time of placing this concrete, the upper spacers of the lowermost spacers are pushed up to the ground side (upward) by the concrete, but the four high tension wires 102
Holds the upper spacers at a predetermined interval C against the pushing force. If necessary, a positioning member may be used to prevent bending of the strip 6 and prevent the cage A from being distorted.

[0033]

As described above, according to the continuous wall construction method of the present invention, the prestress construction method is enabled, and the shield machine can be started and reached without the need for ground improvement or manual destruction of the wellhead. can do.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an example of an apparatus for carrying out the present invention.

FIG. 2 is a front view of FIG.

FIG. 3 is a side sectional view showing a coupler.

FIG. 4 is a perspective view for explaining a cage building process.

[Explanation of symbols]

A: cage S: Wellhead S1 ... predetermined location S2: Depth level range 1 ... Wall groove 2 ... Opening 3 Stabilizer 4 ... reel 6, 6a ... Longitudinal material 7 ... Horizontal strip 8, 8a..Spacing material 10 ... Coupler 11 ... Mounting steel pipe 12 ... Non-shrink concrete 13 ... grease 14 ... Consolidated concrete 20: Coupler sheath

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) E02D 5/20 102-103 E21D 9/06 301 E04C 5/08

Claims (2)

(57) [Claims] 1. A method of excavating a continuous wall groove, and a step of storing a cage inside the continuous channel, wherein the cage is hung from each of a pair of reels. The vertical strips to be lowered are connected by the horizontal strips and the spacing strips, the vertical strips are made of a material having tensile strength and flexibility, and the predetermined portions are made of tensile strength and In addition to being flexible, it is made of a material having a property that it can be easily cut, and the horizontal strips and the spacing strips are made of the same material as the vertical strips at the connecting points. Rooting concrete placing step of placing rooting concrete in the lower part of the wall groove in which the body is built, tensioning step of tensioning the longitudinal strip after solidification of the rooting concrete, and placing concrete Before the concrete pouring process and after the pouring concrete is solidified A tension release process for releasing the tension of the longitudinal strip to give a prestress, and the strip of the new material and the longitudinal strip are connected by a coupler, and the coupler accommodates both strips. A continuous wall construction method comprising a steel pipe and non-shrink concrete in which both strips are embedded in the steel pipe, the coupler is surrounded by a coupler sheath, and the interior of the coupler sheath is filled with grease. 2. A method of excavating a continuous wall groove, and a cage-building step of building a cage in the continuous-wall trench, wherein the cage built in the building step is suspended from each of a pair of reels. The vertical strips to be lowered are connected by the horizontal strips and the spacing strips, the vertical strips are made of a material having tensile strength and flexibility, and the predetermined portions are made of tensile strength and In addition to being flexible, it is made of a material having a property that it can be easily cut, and the horizontal strips and the spacing strips are made of the same material as the vertical strips at the connecting points. A concrete-consolidating step of placing concrete in the lower part of the wall groove in which the body is built, a concrete placing step of placing concrete after solidification of the concrete, and the placed concrete. Before the material is completely solidified, It includes a tensioning step of tensioning and a tension releasing step of releasing the tension of the longitudinal strip after solidification of the cast concrete to give prestress, and the new strip and the longitudinal strip are connected by a coupler. The coupler is composed of a mounting steel pipe containing the both strips and a non-shrinkable concrete in which the strips are embedded in the steel pipe.The coupler is surrounded by a coupler sheath, and the inside of the coupler sheath is filled with grease. The wall construction method characterized by being used.