JP3036295B2 - Construction method of retaining wall - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a retaining wall, and more particularly, to a method for constructing a retaining wall for supporting a lateral pressure such as an earth pressure and a water pressure to prevent collapse or movement of the ground.

[0002]

2. Description of the Related Art For example, when a soft ground is strengthened or when the ground is used as a civil engineering structure, a solid and stable ground improvement body is obtained by mixing a solidified material into the ground or freezing the ground. A consolidation method is often employed. And when such an improved body is formed as a retaining wall or a retaining wall for preventing the movement of the ground due to landslide or the like when performing the open-cutting method, since such an improved body has a small strength against a tensile force. It is necessary to design an improved body so that a large tensile stress does not occur due to a moment or the like. That is, in order to stably support a large side pressure, it is necessary to form an improved body with a large improvement width in the direction of the side pressure load.

[0003]

While only INVENTION Problems to be Solved the case of using the soil improvement material as walls for earth retaining, the reclamation work for improvement body for high construction costs, it is uneconomical to take large improvements width At the same time, there is a problem that it is difficult to form a stable retaining wall at a work site where a sufficient improvement width cannot be obtained, such as when an improved body is formed adjacent to an existing structure.

In the open-cutting method for excavating one side surface of the improved body, a method of inserting a reinforcing steel material along the cut surface to enhance the rigidity of the improved body has been adopted. In order to obtain rigidity, a steel material having a large section modulus is required, so that there has been a problem that rational and economical design and construction cannot be performed.

Accordingly, the present invention has been made to solve the above-mentioned problems, and is a retaining wall using a ground improvement body, which does not require a large improvement width, and is designed and economically designed. How to construct a retaining wall that can perform construction and stably support soil pressure
The purpose is to provide the law .

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned object, and a gist of the invention is a method of constructing a retaining wall constructed to support lateral pressure such as earth pressure and water pressure. And a number of ground improvement piles,
How to apply lateral pressure to a ground improvement body with a predetermined width by the ground improvement method
After crossing the direction and extending, the ground improvement body is solidified ,
And Da設pre Katakui body along the side edge portions of the lateral pressure load forward of該地board improved body, while pouring a post Katakui body along the side edge portions of the lateral pressure load aft of the soil improvement material , in the construction method of the earth retaining wall member, characterized that you set up a tension member connecting the rear Katakui body and the front pile body.

Here, as the front pile body and the rear pile body, not only various steel materials such as H-shaped steel, I-shaped steel, steel sheet pile, steel pipe pile, but also PC piles can be used.

[0008]

According to the construction method of the retaining wall having the above structure, the ground improvement body is composed of a front pile body and a rear pile body which are driven along both sides of the ground improvement body, and the front pile body The body and the back pile are integrated by the action of a tensile member. That is, since the improved body and the pile body integrally resist the lateral pressure by the action of the tensile member, the required improvement width of the ground is reduced, and the lateral pressure can be efficiently and stably supported.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. The construction method of the retaining wall according to the present invention is suitable.
The retaining wall 10 in the preferred embodiment used is shown in FIG.
As shown in the figure, when constructing a structure underground by the open-cutting method, without providing a stake support member such as a cut-off beam that becomes an obstacle to excavation in the open-cut portion, the earth pressure from the surrounding soft ground E It was created to stably support lateral pressure such as water pressure.

That is, the retaining wall 10 of this embodiment
Is a ground improvement body 11 having a predetermined width formed by various ground improvement methods, and is placed and installed at predetermined intervals along the front surface of the ground improvement body 11, that is, the side surface of the ground improvement body 11 on the side of the cut-out portion. A front H-shaped steel 12 as a front pile body,
The rear H as a rear pile, which is placed and installed at a predetermined interval corresponding to the front H-beam 12 along the rear surface of the ground improvement body 11, that is, along the side surface of the ground improvement body 11 on the soft ground E side. It is composed of a shaped steel 13 and a tensile member 14 that connects the front H-shaped steel 12 and the rear H-shaped steel 13 across the ground improvement body 11.

In order to form the earth retaining wall 10, first, a ground improvement body 11 is formed around a portion to be cut. As an example, the ground improvement body 11 is formed by placing a large number of columnar ground improvement piles 17 vertically and horizontally in the formation area of the ground improvement body 11 by the deep mixing pile method shown in FIG. That is, in this deep mixing pile method, after the rotating rod 16 is driven to a predetermined depth by the pile driving machine 15, ((a) to (c))
By pulling out the solidified material from the tip of the rotating rod 16 while supplying the solidified material (see (d)), the ground improvement pile 17 in which the soil and the solidified soil and the solidified material are mixed and stirred is sequentially formed. (See (e)).

A ground improvement body 11 is formed, and the ground improvement body 1
1 is solidified , the front H-beam 12 and the rear H-beam 13
In order to attach the tension member 14 and the ground improvement body 11, the ground improvement body 11 is provided with a mounting groove having a cut section shown in FIG. 4 by using a thin groove excavator 18 shown in FIG. 19 is formed by excavation. This thin groove excavator 18 is a known one disclosed in, for example, Japanese Patent Application Laid-Open No. 2-221519, and has a pair of drilled portions 20 having a circular cross section and a pair of chain cutters 21 provided therebetween. And suspended from a base machine (not shown) such as a crane,
The mounting groove 19 is dug vertically in the ground by its weight. That is, the circular excavation hole 22 is
0, the vertically elongated slots 23 are respectively excavated and formed by the chain cutter 21. The mounting groove 19 does not necessarily need to be formed by excavating the entire length of the ground improvement body 11 in the vertical direction (see FIG. 6). It is appropriately designed in consideration of the supporting force, the size, and the like of the H-shaped steel 13.

As shown in FIGS. 5 and 6, the front H-shaped steel 12 and the rear H-shaped steel 13 are inserted into the excavated holes 22 at both ends of the mounting groove 19 formed by excavation. Also, the front H
Between the section steel 12 and the rear H section steel 13, a tension member 14 for connecting them is installed in the longitudinal slot 23. Here, as shown in FIG. 7, the pair of fitting members 24 fixed to both ends of the tensile member 14 are fitted to the flanges 25 of the front H-shaped steel 12 and the rear H-shaped steel 13, respectively. By sinking as a guide, it can be easily installed at a predetermined position. The tension member 14
It is not necessary to apply a tension in advance, but at least a strength for supporting a ground improvement body 11 between the front H-section steel 12 and the rear H-section steel 13 when a tensile force is about to act thereon. For example, a steel rod, a steel wire, a steel sheet pile, a wire, or the like is used.
In addition, when installing the front H-shaped steel 12, the rear H-shaped steel 13, and the tension member 14, the inside of the mounting groove 19 is filled with, for example, bentonite muddy water to maintain the stability of the wall surface.

When the installation work of these members is completed, cement milk is injected from the bottom of the mounting groove 19 through, for example, an injection rod or the like (not shown), and is replaced with bentonite mud and solidified. Thus, the ground improvement body 11, the front H-section steel 12, the rear H-section steel 13, and the tensile member 1
The construction of the retaining wall 10 in which the four are integrated is completed.

As shown in FIG. 8, the rear H-shaped steel 13 is excavated by about 1 to 2 m between adjacent rear H-shaped steels 13, and a connecting steel material 26 is installed there. It is preferable to continuously integrate the tops of the thirteen. 5 and 6
8 and FIG. 8, reference numeral 30 denotes a belly-raising member, which is provided on the front H-shaped steel 12 at a plurality of steps with the progress of excavation of the cut-out portion after the formation of the retaining wall body 10, and It is intended to be integrated.

[0016] Then, according to the volume of soil distillate wall member 10 Construction in the above steps, ground improvement body 11 and the front H-beams 12 and rear H-beams 13 and the tensile member is Da設on both sides of this 14 can efficiently and stably support lateral pressure such as earth pressure and water pressure.

Further, in the above embodiment, the case where the H-section steel is cast as a front pile on the cut surface side of the ground improvement body 11 has been described. The use wall 10 can also be formed. That is, in this case, the ground improvement body 11 is formed at a distance of about 50 to 100 cm from the driving line of the steel sheet pile,
The mounting groove 19 is excavated so that one excavation hole 22 of the mounting groove 19 is located on the driving line of the steel sheet pile. When the steel sheet pile is driven along the driving line,
A steel sheet pile 31 (see FIG. 9) to which an H-shaped steel 32 is firmly fixed by welding or the like is previously placed on the back surface, and the tensile member 1 is placed at a predetermined position using the H-shaped steel 32 and the rear H-shaped steel 13 as guides.
The attachment 4, further a gap between the soil improvement material 11 and the steel sheet pile solidified for example by ground improvement method, such as high-pressure injection pile method, so as Ru FIG both integration of.

In the above embodiment, the case where the retaining wall of the present invention is used as a wall for retaining in a digging method has been described, but the method of constructing the retaining wall of the present invention is limited to such a wall. is the not may Rukoto be applied to the ground in the wall of formed like in order to prevent other than for example ground collapse or movement or the like.

[0019]

As described in detail above, the method for constructing a retaining wall according to the present invention can be implemented by a predetermined ground improvement method.
Forming a ground improvement body with constant width so as to intersect with the load direction of lateral pressure
After the ground improvement body is solidified, the lateral pressure of the ground improvement body is reduced.
Driving a front pile along the side end in the loading direction,
Aft pile along the side edge of the panel improvement body
And the rear pile and the front pile are connected.
The ground improvement body, front pile body and
And the back pile and the tension member are integrated to resist side pressure such as earth pressure and water pressure, so that such side pressure can be supported efficiently and stably, and the necessary improvement of the ground is reduced and the cost is reduced. It has a special effect that it can be created in a small area.

[Brief description of the drawings]

FIG. 1 shows a method for applying a retaining wall body according to the present invention.
It is a perspective view which shows one Example of the wall for earth retaining .

FIGS. 2 (a) to 2 (e) are explanatory views showing steps of performing ground improvement by a deep mixing pile method.

FIG. 3 is a side view showing an example of a means for excavating and forming a mounting groove for mounting a front pile body, a rear pile body, and a tension member on the ground improvement body.

FIG. 4 is a plan view showing a cross-sectional shape of a mounting groove.

FIG. 5 is a plan view showing details of the configuration of a retaining wall according to one embodiment constructed by the construction method of the present invention.

FIG. 6 is a side sectional view showing details of a configuration of a retaining wall body according to an embodiment constructed by the construction method of the present invention.

FIG. 7 is a plan view showing a situation where a tensile member is mounted between a rear pile and a front pile.

FIG. 8 is an explanatory view showing a situation in which the rear piles are continuously integrated.

FIG. 9 shows a case where a steel sheet pile is used as a front pile.
It is a top view showing the situation where a tension member is attached between a back pile and a front pile.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Soil retaining wall 11 Ground improvement body 12 Front H-section steel (front pile) 13 Rear H-section steel (rear pile) 14 Tensile material

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-315520 (JP, A) JP-A-59-224720 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) E02D 5/18-5/20 E02D 3/12 E02D 17/04

Claims (1)

(57) [Claims] 1. A method for constructing a retaining wall constructed to support lateral pressures such as earth pressure and water pressure, wherein the method comprises a plurality of vertical and horizontal grounds.
The ground is improved by a prescribed ground improvement method such as placing an improved pile.
Forming a ground improvement body with constant width so as to intersect with the load direction of lateral pressure
And, after the該地Release improved body has solidified, and Da設pre Katakui body along the side edge portions of the lateral pressure load forward of該地board improved body, the side end portion of the lateral pressure load aft of the soil improvement material Katakui body after along
The while pouring, the earth retaining wall member, characterized that you set up a tension member connecting the rear Katakui body and the front pile body
Construction method .