JPS6051220A - Improvement work of ground - Google Patents

Abstract

PURPOSE:To obtain a uniform soil cement by breaking soil lumps by a vibrator attached to the central shaft of an earth auger in mixing cement milk with soil. CONSTITUTION:The ground 1 is excavated by an excavating blade 4 provided to the tip of a screw blade 3 formed around the central shaft of an earth auger 2 to form a hole 5 for forming soil cement column. While injecting cement milk 6 into the hole 5, the milk is mixed with soil in the hole 5 with stirring, during which period vibration is applied to the earth auger by a vibrator attached to the central shaft of the earth auger, as shown by arrow 7, to break soil lumps, and the cement milk 6 is mixed with the soil with stirring to form a soil cement column.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a construction method for ground improvement in which soil cement columns are prepared in advance to strengthen the ground when constructing a house or the like in a soft ground area.

(Conventional technology) Conventionally, when constructing a building on soft ground, methods such as driving concrete piles and piles into hard ground have not been adopted in the case of doll structures, but this method It requires a huge amount of money and is not suitable for general residential use. In addition, cement milk is injected into the soil as a ground strengthening method for general housing.
It is also used to strengthen the ground by mixing it with soil to form -C soil concrete.

However, this method has the disadvantage that when the soil is clayey, lumps occur in the excavated soil and it does not mix well with the cement mill, making it impossible to form a sufficiently homogeneous noil cement column.

(Objective of the Invention) In order to solve the above-mentioned drawbacks, the present invention aims to (d) excavate soft ground with an earth auger, inject cement milk from the tip of the earth auger, and When making fill cement columns by stirring the cement mill and soil while rotating the horn, homogeneous soil cement is obtained by loosening the soil clods by the vibration of the vibrator attached to the central axis of the horn. It is intended to enable

(Structure and operation of the invention) Figure 1 is for explaining the soil improvement construction method of the present invention.d)
FIG. 2 is a vertical cross-sectional view showing the configuration of the first embodiment.

This is done by excavating a soil area 1 with a tip excavating blade 4 of a screw blade 3 formed around the central axis of an earth auger 2 to form a hole 5 for forming a fill column. When the cement milk 6 is injected into the earth auger 2 to mix it with the soil inside, a vibrator (not shown) attached to the shaft of the earth auger 2 causes the earth auger itself to vibrate as shown by the arrow 7. is added, and the cement milk 6 and the soil are stirred while loosening the soil clods to form a mail cement column.

FIG. 2 is a vertical sectional view showing the structure of a second embodiment of the present invention.

In the figure, 1 to 5 indicate the same parts as shown in FIG.

The feature of this embodiment is that a rod-shaped pie break 8 used for vibration compaction of concrete 1 is passed through the central axis of the earth auger 2, and the tip excavation blade 4 at the tip of the earth auger 2 is inserted into the center shaft of the earth auger 2.
When the earth oat no 2 stirs the cement milk and soil that have flowed into the fill cement forming hole 5, the rod-shaped vibrator 8 breaks up the soil lumps and forms a uniform column of noil cement. This method improves the ground by building a structure and placing it in a desired position on the soft ground on which a building is to be constructed.

FIG. 3 is an example of a work process diagram for explaining the construction method of the present invention, in which 1 to 2 show the excavation process, 2 to 2 the cement milk injection process, and 2 to 3 the mixing and stirring process. Here, the /ibrator is used in the mixing and stirring step, but is not shown.

Next, the work order will be explained.

■ Seven holes of excavation started using Earth Auger 2 as the center of the pile, ■
During excavation, ■ Excavation completed, seven-ment milk injection started,
■ Seven mento milk is being poured, ■ Cement mino paste is poured, mixing and stirring of soil and cement milk starts, ■ Mixing and stirring of soil and cement milk is in progress, ■ Mixing and stirring (first time) is completed to the required pile length, ■ Required During mixing and agitation (second time) using a double bar pulled from the pile length, ■ Mixing and agitation is completed. Pile formation completed.

(Effects of the Invention) As explained below, according to the present invention, when mixing cement milk and soil, it is easy to loosen the soil clod into fine and homogeneous particles using pipe raking, so that soil with extremely uniform particles can be obtained. It has the advantage that cement can be obtained and that stable ground improvement using soil cement columns with good properties can be formed at a low cost on soft ground areas.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view showing the configuration of a first embodiment of the present invention for explaining the soil improvement construction method, and FIG. 2 is a vertical sectional view showing the configuration of the second embodiment of the present invention. FIG. 3 is a diagram showing an example of the working process according to the present invention. ■・・・・・・Soil part, 2・・・・Earth auger, 3・・・・Screw blade, 4
・・・・・・Tip excavation blade, 5・・・・・・・・・Hole part for forming soil cement column, 6 ・・・・・・・・・・・・
・Cement milk, 7... Vibration of the earth auger itself due to pie break, 8... Rod-shaped vibrator. Patent applicant Niso Kenkiso Consulta/To Co., Ltd. Figure 1 Figure 2

Claims (2)

[Claims] (1) A hollow cylindrical body with a screw blade along the outer periphery of the center, a tip drilling blade at the tip of the center shaft, a pie break attached to the hollow center shaft, and a cement milk inlet. Using an earth auger equipped with an earth auger, excavate the soft ground made of soil with the earth auger to form a hole of a desired depth, and inject cement milk into the hole and supply soil. When stirring this with the earth auger, the process of loosening and stirring the soil clods with the vibrator to form soil cement is carried out from the bottom of the hole while sequentially pulling up the earth auger with a two-part swivel. 1. A construction method for ground improvement, characterized by forming a mail cement column within the section and repeatedly applying this to each of the required locations having the soft ground. (2) The pie break is a rod-shaped body that is installed in the hollow central shaft of the earth auger so that it can slide up and down. The ground improvement method 1' according to claim (1), characterized in that the device protrudes from the F section and can vibrate.