JPH0751770B2 - Ground improvement method for construction - Google Patents

Description

TECHNICAL FIELD The present invention relates to an improved construction method for building ground.

(Prior Art) Conventionally, a method of improving the surface soil of the ground by using a cement-based solidifying material (referred to as Conventional Example 1), a method of reinforcing the ground by adding a reinforcing material (referred to as Conventional Example 2), a reinforcing material in the embankment There was a construction method (referred to as Conventional Example 3) in which the ground is put in to strengthen the ground.

(Problems to be Solved by the Invention) In Conventional Example 1, the compressive strength is increased, but the tensile strength is not, and there is a problem that, for example, when a vertical compressive force is applied to the ground, cracks easily form in the ground. It was

The conventional example 2 has a problem in that the soil is disturbed when the reinforcing material is inserted, and the compressive strength is weakened.

In the conventional example 3, since the reinforcing material is put in the embankment, there is a problem that the ground is insufficiently compacted.

(Means for Solving Problems) The present invention is to reinforce the existing ground over the entire construction site by excavating the topsoil to remove the topsoil and forming a grid or mesh on the base bottom of the bottoms of the topsoil removed. A new material of high quality is laid on the reinforcing material to a suitable thickness, and the new material is mixed with the solidifying material and stirred, and then compacted to form the ground for construction. It is an improved construction method.

(Function) By placing a reinforcing material on the ground from which the soft topsoil has been removed, and by adding new high-quality earth and sand to this to construct the upper ground, it is possible to improve the compressive strength and shear strength of the ground. Increase tensile strength.

(Example) Drawing shows the Example of the ground improvement method for construction of this invention.

First, the existing ground 1 in the entire building ground is excavated by using an excavator (not shown) or the like to remove the topsoil 2 having a depth of about 300 mm to 500 mm (see FIG. 2). The thickness of the topsoil 2 to be removed may be 200 mm in consideration of the softness of the topsoil 2, or 700
It may be necessary for about mm.

In this way, the reinforcing material 4 formed in a lattice shape, a mesh shape or the like is arranged on the base bottom 3 of the ground from which the top soil 2 has been removed (see FIG. 2).

As the reinforcing material 4, for example, plastic, rebar, bamboo, rope, cloth or the like is used. The reinforcing material 4 is basically formed in a lattice shape or a mesh shape, but it may be assembled in a single direction.

In this way, a new quality sand 5 is laid on the base bottom 3 on which the reinforcing member 4 is arranged in an appropriate thickness, and an appropriate amount of the solidifying material 6 is sprinkled on the new sand 5 ( (See FIG. 3).

As the high-quality new earth and sand 5, it is preferable to use well-drained mountain sand, river sand, sea sand, Masa earth, etc. alone or in combination.

As the solidifying material 6, a ground safety treating agent, cement or the like is used alone or in combination. As the ground stabilization agent, for example, Fuji Beton (trade name of Keio Kaken Kogyo Co., Ltd.) or Asano Clean Set 1140 (trade name of Nippon Cement Co., Ltd.) is suitable.

Improved soil 7 is prepared by mixing and stirring new earth and sand 5 with an appropriate amount of solidified material 6 dispersed therein using an excavator (see FIG. 4).

The surface of the improved soil 7 thus mixed and stirred is leveled by, for example, a bucket of an excavator, and the improved soil 7 is temporarily rolled.

After the temporary rolling pressure is completed, the level of the improved soil 7 is measured, and the operator corrects the place where the level difference is large or the place where there is uneven mixing.

After the correction of the level difference and the like, the improved soil 7 is finally compacted by using a roller or the like (not shown).

After the completion of this compaction, water is sprinkled on the improved soil 7 to adjust the water content ratio.

The upper ground 8 is constructed by taking an appropriate curing period.

In this way, by constructing the improved upper ground 8 on the reinforcing member 4 arranged on the base bottom 3, the ground 9 is constructed (see FIG. 5).

The upper ground 8 may be formed by being divided into a plurality of layers, and the reinforcing material 4 may be arranged between the respective layers.

FIG. 6 shows a state in which the construction ground 9 thus configured is bent due to uneven subsidence or the like. Reference symbols A, B, in the figure
Especially tensile force is generated in C.

Even when the ground is bent in this manner, the reinforcing material 4 shares the tensile force of the soil and suppresses the tensile force of the soil, so that the rigidity of the ground is increased and cracks do not occur.

(Effect of the invention) Reinforcing material formed in a grid or mesh shape is arranged on the ground from which the soft topsoil has been removed, and new high quality earth and sand is laid on this reinforcing material for improvement. The upper ground which was done is constituted. Therefore, it is possible to obtain a building ground with improved compressive strength / shear strength and tensile strength.

Since the ground is improved over the entire area of the building site, not only the foundation part, but also the part where the meteorite is installed is strong.

Even if uneven subsidence occurs, the ground has tensile strength, so that the ground does not crack. Therefore, the building built on such ground is stable.

[Brief description of drawings]

1 to 5 show the procedure for carrying out the ground improvement method for construction of the present invention. FIG. 1 is a cross-sectional view of the building land, and FIG. 2 is a reinforcing material provided on the base bottom of the ground from which the topsoil has been removed. Cross section,
Fig. 3 is a cross-sectional view in which high quality new earth and sand is put on the base bottom where the reinforcing material is arranged and the solidifying material is sprinkled on the new earth and sand, and Fig. 4 is of high quality. Sectional view of improved soil prepared by mixing and stirring new soil and solidifying material, No. 5
The figure is a cross-sectional view of the ground for construction completed by constructing the upper ground,
FIG. 6 is a cross-sectional view showing that the reinforcing material suppresses the tensile force of the soil even if the building ground thus completed is unevenly settled. 1… Current ground 2, 2 Topsoil 3… Base bottom 4… Reinforcement material 5… New quality sand, 6… Solidification material 7… Improved soil, 8… Upper ground 9… Construction ground A, B, C… Tensile force

Claims (1)

[Claims] 1. A ground material is excavated over the entire area of a building site to remove surface soil, and a reinforcing material formed in a lattice shape, a mesh shape or the like is disposed on the base bottom of the ground surface soil removed. A construction ground improvement method characterized by laying a new good quality sand on top of the above with a suitable thickness, mixing and stirring this new sediment and solidifying material, and then compacting it to form a building ground.