JPS63138015A - Improving construction for construction site - Google Patents

Abstract

PURPOSE:To stabilize a site to construct the foundation of a structure, by mixing and stirring earth and solidifying material with each other, after surface soil is removed from actual ground and the earth and the solidifying material of good quality are sprayed on the base bottom. CONSTITUTION:Actual ground in the whole constructing site is excavated by an excavator 1, and the surface soil of the thickness of approx. 300-500mm is removed from. After that, on the base bottom 4 of the ground with the removed surface soil, the earth 10 of good quality is laid in proper thickness, and on the earth 10, the solidifying material 5 of cement or the like is sprayed. Then, the solidifying material 5 and the earth 10 are mixed and stirred with each other by the excavator 1, and while the level of improved soil 7 is corrected, the improved soil 7 is rolled, and on the improved soil 7, water is sprayed, and water content rate of dry weight is regulated. As a result, after a given curing period, the foundation of a structure can be constructed on the improved site.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a ground improvement method for construction aimed at preventing uneven settlement of buildings due to soft ground or destruction of concrete foundations.

(Conventional technology) Conventionally, when building a house on soft ground, ground countermeasures have been taken using a slab foundation, pile foundation, etc.

(Problems to be Solved by the Invention) A solid foundation is effective in sandy ground, and in clay ground it is effective in reducing the ground contact thickness, but the construction cost is extremely high and it is uneconomical.

In addition, pile foundations pose environmental pollution problems due to noise and vibration during driving, and are an uneconomic construction method because the construction cost is considerably higher than the total building cost.

(Means for Solving the Problems) The construction ground improvement method of the present invention involves excavating the existing ground over the entire area of the construction site, removing the topsoil to a depth of approximately 300 to 500 mm, and removing the topsoil in this way. Lay a suitable thickness of new high-quality soil on the base bottom of the removed ground, sprinkle an appropriate amount of solidification material on this new soil, and then mix and stir this new soil and solidification material. Improved soil and
The surface of the improved soil is leveled and preliminary compaction is performed, then the level of the improved soil surface is adjusted, then the main compaction is performed, and the improved soil is sprinkled with water to adjust the moisture content and cured. It is.

(Operation) The topsoil, which is generally soft, is removed over the entire area of the construction site, and new, high-quality soil is laid on the base bottom of this removed ground, and an appropriate amount of solidification material is spread on top of this new soil. Then, this solidified material and new earth and sand are mixed and stirred to form improved soil, thereby improving the ground for construction.

(Example) The drawings show an example of the construction ground improvement method of the present invention.

First, an excavator 1 is used to excavate the existing ground 2 over the entire area of the construction site, and topsoil 3 with a thickness of approximately 300 to 500 fl is removed. Considering the softness of the topsoil 3, the thickness of the topsoil 3 to be removed may be 200 m, or 700 m or less.

New earth and sand 10 of good quality is laid with an appropriate thickness on the base bottom 4 of the ground from which the topsoil 3 has been removed in this way, and an appropriate amount of solidification material 5 is sprinkled on this new earth and sand 10. As the solidifying material 5, a ground stabilizing agent, cement, etc. may be used alone or in combination. As the ground stabilization treatment agent, for example, Fujibeton (trade name of Keio Kaken Kogyo Co., Ltd.) or Asatsu Clean Set 1140 (trade name of Nippon Cement Co., Ltd.) is suitable.

Further, as the new soil 10 of good quality, it is preferable to use well-drained mountain sand, river sand, sea sand, masa soil, etc. singly or in combination.

New earth and sand 10 sprinkled with an appropriate amount of solidification material 5 are mixed and stirred using the same excavator 1 to achieve an improvement of ±7 (3rd stage).
(see figure).

The surface of the improved soil 7 mixed and stirred in this manner is leveled using, for example, an excavating bucket (la) of the excavator 1, and the improved soil 7 is subjected to temporary axial pressure.

After the temporary axial pressure is finished, the level of the improved soil 7 is measured, and the operator corrects areas where the level difference is large or where there is uneven mixing.

Further, improvement ±7 is carried out by using a run 78, a roller 9, etc., to carry out the main rolling.

After the main compaction is completed, the level of improvement ±7 is reconfirmed, and water is sprinkled on this improvement ±7 to adjust the water content ratio.

After a suitable curing period, the ground improvement is completed.

The foundation will be constructed on the ground that has been improved as described above.

(Effects of the invention) The construction ground improvement method of the present invention removes the topsoil of the current ground over the entire building site to an appropriate depth, and then lays new soil of good quality on the ground from which the topsoil has been removed. This new soil and solidification material are mixed and stirred to create improved soil.

Therefore, since the topsoil, which is a soft ground, is removed and new soil of good quality is laid, the improvement effect is enhanced and the building can be constructed on stable ground.

[Brief explanation of the drawing]

The drawings show an embodiment of the construction ground improvement method of the present invention, and the first
The figure is a cross-sectional view of the current ground being excavated using an excavator, Figure 2 is an enlarged cross-sectional view of the new earth and sand that has been laid on the base bottom, and the solidification material has been spread on it. Figure 3 is the base bottom with the solidification material sprinkled on it. Figure 4 is a cross-sectional view of a worker leveling the surface of improved soil, and Figure 5 is a cross-sectional view of improved soil being formed by mixing and stirring while excavating it to an appropriate depth. Fig. 6 is a sectional view showing improved soil being rolled using rollers. 1... Excavator 2... Current ground 3...
・Top soil 4...Base bottom 5...Solidification material 7...Improved soil 1a...Drilling packet 8...Run 7 9...Roller 10...
・A new, high-quality earth and sand agent Yoshiaki Kurauchi, patent attorney, ゛・－：・ツ No. 7
Figure 2 ---F-1-

Claims (1)

[Claims] 1) Approximately 300 acres were excavated from the current ground throughout the entire construction site.
Remove the topsoil to a thickness of ~500mm, lay new high-quality earth and sand to an appropriate thickness on the base bottom of the ground from which the topsoil has been removed, and place an appropriate amount of solidification material on top of this new earth and sand. After spreading, this new soil and solidification material are mixed and stirred to make improved soil, the surface of the improved soil is leveled and preliminary compaction is performed, and then the level of the improved soil surface is adjusted before the actual rolling. A construction ground improvement method characterized by compressing the compacted improved soil, sprinkling water on it to adjust the moisture content, and curing it.