JPH0629498B2 - Soft ground treatment method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a ground treatment method performed when reinforcing soft ground.

[Prior Art and Problems to be Solved by the Invention]

The ground treatment here is to increase the bearing capacity such as maintaining the shape of the local embankment and the edge of the embankment, preventing depression and slip failure, and suppressing differential settlement. Alternatively, it is carried out on low embankment roads, construction roads, etc. in order to secure the bearing capacity against the load of the embankment itself and the repeated load of trucks and the like.

As a conventional treatment method of this kind, a shallow layer mixing treatment method, a sheet method, a raft sedimentation method, etc. are generally known. However, in the shallow layer mixing treatment method, it is necessary to add a curing agent to the original ground, so that strength management becomes troublesome. Also, in the sheet construction method, only reinforcement of the tensile material,
It is inadequate for bending reinforcement. Furthermore, raft sedimentation is a severe deterioration of materials. The present invention has been made in view of the above circumstances. Its purpose is that strength management is easier than in the shallow layer mixing method, and deterioration of the material is unlikely to occur in the raft flooring method, etc., and a large reinforcing effect can be achieved by using a relatively small amount of hardening material. It is to propose a method for treating soft ground.

[Means for Solving the Problems]

This method for treating soft ground has a plurality of columnar reinforcements made by compressing and filling hardened material consisting mainly of coal ash into a cloth bag with high strength and long water permeability, which is arranged in parallel or in the cross direction on the soft ground. It is characterized by laying and embankment on it.

The cloth bag used in the present invention is permeable to water, has high strength, and has an appropriate degree of elongation, and is preferably made of synthetic fibers such as polyester, nylon, polyethylene, and polypropylene. The shape thereof is a long bag shape, and as shown in Examples described later, it may be of an independent type or may be integrated with a sheet. The hardening material is a mixture of coal ash as a main material and cement, gypsum, etc. as an additive material, and is used for construction without adding a proper amount of water to form a slurry.

The columnar reinforcing materials are oriented in parallel or in a crossing direction such as a cross girder corresponding to the stress acting on the ground, that is, they are laid in a raft shape.

〔Example〕

The processing method of the present invention will be described below with reference to illustrated embodiments.

In order to reinforce the soft ground by this treatment method, the cloth bag is arranged at a predetermined position on the ground in a predetermined direction, and the curable material in the form of slurry is injected under pressure to dehydrate and fill the cured material. A plurality of columnar reinforcing materials are formed and laid by being solidified without being integrally formed with the bag body, and the embankment is embanked on it.

In the embodiment shown in FIG. 1, a columnar reinforcing material 3 having a circular cross section, which is made by filling a long cloth bag 2 with a hardening material on a soft ground 1, is laid in a cross girder shape, that is, in two orthogonal directions, and an embankment 5 is placed thereon.
It is an example of the processing method which gave.

In the embodiment shown in FIGS. 2, 3 and 4, a plurality of side-by-side cloth bags 2 integrally formed with the sheet 4 are filled with a hardening material, and a columnar reinforcing material 3 having a rectangular cross section is orientated in the parallel direction. This is an example of a process in which the embankment 5 was performed thereon.

FIG. 5 shows an example of arranging the mold 6 on the outside of the cloth bag 2 and filling the hardening material to form the columnar reinforcing material 3 having a rectangular cross section.

A long cloth bag is not necessarily a single one. For example, a long cloth bag may be connected in the vertical and horizontal directions so as to communicate with each other, and the inside may be filled with a hardening material to form a columnar reinforcing material connected to a rice field pattern or the like. It is also possible to lay the upper columnar reinforcing material in a direction orthogonal to the lower columnar reinforcing material so as to be stacked.

In order to improve the bending rigidity (proof strength) of the reinforcing material 3, a mesh-like reinforcing material (not shown) having a large tensile strength may be arranged on each reinforcing material 3 as tensile reinforcement.

[Operation and effect of the invention]

The present invention is configured as described above. In this processing method, the column-shaped reinforcing member is formed by integrating the outer high-strength cloth bag and the inner hardened material into one body, and exhibits a large bending strength. Since the sectional height can be made larger than that of the reinforcing board, it contributes greatly to the improvement of the bending strength of the soft ground and the reinforcing effect can be enhanced.

The reinforcing effect can be further enhanced by orienting and arranging the long columnar reinforcing material in parallel or in a direction intersecting with the effective direction with respect to the applied external stress. For example, in a long structure such as a road, the reinforcement effect and the economical efficiency can be improved by arranging the columnar reinforcing members in parallel in the direction orthogonal to the length direction.

Since the cloth bag is strip-shaped, it is easy to handle, and it can be placed on soft ground and filled with a hardening material to easily and accurately form and lay a columnar reinforcing material without defects.

Since the curable material is mainly made of spherical coal ash having a small specific gravity, the slurry has good fluidity, is easily dehydrated under pressure, and contributes to the strength development of the columnar reinforcing material.

This processing method has the following effects.

-The effect of reinforcement is greater than the conventional sheet construction method or reinforcement by a reinforcing board, etc., and a large proof stress against the embankment load and the stress acting on it can be given to the soft ground.

・ Efficient construction is possible without using special machinery.

-Since the hardening material is not added directly to the original ground, strength management becomes easy and it can be applied to soil improvement of organic soil.

-Does not cause material deterioration such as conventional raft sinking.

[Brief description of drawings]

FIG. 1 is a sectional view of the ground treated by the method of the present invention, FIG. 2 is a sectional view of the ground treated by another aspect of the method of the present invention, and FIG. 3 is a sectional view taken along the line AA of FIG. FIG. 5 is a perspective view of a portion B in FIG. 3, and FIG. 5 is a sectional view showing a manufacturing state of a columnar reinforcing material having a rectangular cross section. 1 ... Soft ground, 2 ... cloth bag, 3 ... columnar reinforcement, 4 ...
… Sheet, 5 …… Embroidery, 6 …… Formwork.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP 61-165412 (JP, A) JP 63-184607 (JP, A) JP 56-41766 (JP, B2)

Claims (1)

[Claims] 1. A plurality of columnar reinforcing materials, which are obtained by pressurizing and filling a hard permeable material having a high strength and a hard permeable material mainly composed of coal ash, are laid on a soft ground in parallel or in a cross direction.
A method for treating soft ground, characterized by embankment on top of it.