JPH08158357A - Drilling agitator for soil cement pile method - Google Patents

Abstract

PURPOSE: To simplify the working operation, by detachably attaching soil- discharging blades having a larger area than agitating blades to the agitating blades at the front end of a rotary shaft. CONSTITUTION: A plurality of pairs of agitating blades 2 are installed at the outer periphery of a rotary shaft 1 and excavating blades 5 are attached to the outer periphery of the front end of the rotary shaft 1 through blades 6 fitting the excavating blades. When operating it, soil-discharging blades 3 having a larger area than the agitating blades 2 are fitted to the agitating blades 2. After rotation of the rotary shaft to excavate the ground, it is pulled up and the excavated soil is removed. After removal of the soil-discharging blades 3 out of the agitating blades 2, cement milk is poured. And further, excavation and charge of cement milk are repeated by turns to form a soil cement pile.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drilling stirrer used in a soil cement pile method.

[0002]

2. Description of the Related Art The soil cement pile construction method is (1) a method in which the field board is first dug, and then cement milk and earth and sand are stirred and mixed while pouring cement milk into the hole, (2) the field board is dug in advance. However, in each case, the volume of earth and sand is equivalent to the volume of cement milk to be injected into the ground. Moreover, since this earth and sand overflows from the soil, and this earth and sand contains cement, the earth and sand that has flowed out is treated as industrial waste because it pollutes the environment, resulting in high disposal costs and high costs.

As a countermeasure against this, in the construction method (1), it is known that when digging, a volume of earth and sand corresponding to the volume of cement milk to be injected later is discharged.

[0004]

However, the construction method (1) is adopted in the construction of a relatively large-scale pile,
It is necessary to use at least two types of machines for emptying, injection of cement milk, and mixing and stirring. Applying this prior soil removal treatment to the construction method (2) adopted for relatively small-scale pile construction requires the introduction of a new excavator for soil removal. However, the cost will be further increased.

The present invention has been made in view of the above problems, and an object thereof is to propose a drilling stirrer for constructing a relatively small-scale soil cement pile. By using it, it becomes possible to construct soil cement piles by a simple operation without discharging cement milk or cement-containing soil that may cause hard environment pollution.

[0006]

DISCLOSURE OF THE INVENTION The present invention provides a single machine for the work of constructing soil cement piles such as drilling, injecting cement milk, and stirring and mixing cement milk and earth and sand, and the soil discharging operation accompanying it. It is an invention made from the viewpoint of carrying out in.

That is, the present invention is a drilling stirrer for the soil cement pile construction method, in which an agitating blade at the tip of the rotary shaft is detachably attached with a soil discharging blade having a larger area than the agitating blade.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

1A and 1B show the tip of a hole agitator of the present invention. FIG. 1A is a perspective view of the excavator blade attached, FIG. 1B is a side view of the excavator blade attached, and FIG. It is a bottom view of an earth removal blade.

FIG. 2 is a vertical cross-sectional view showing the steps of a construction example of constructing a soil cement pile using the hole agitator of the present invention.

The main body of the drilling stirrer of the present invention is no different from the usual drilling stirrer for the soil cement pile construction method. The difference is that, as shown in FIGS. 1 (a) and 1 (b), a soil removal blade 3 having a larger area than the stirring blade 2 is detachably attached to the most advanced stirring blade 2. Although not shown, the rotary shaft 1 is provided with a cement milk injection pipe inside and a cement milk jetting hole at the tip, as in a normal hole agitator. A plurality of pairs of stirring blades 2 are provided on the outer periphery, and the excavating blade 5 is attached to the outer periphery of the tip via an excavating blade attachment blade 6. The rotary shaft 1 can be rotated in both normal and reverse directions as usual, and can be raised and lowered. Although the soil discharging blade 3 is not attached to the stirring blade 2 at the time of drilling for soil cement pile construction, injecting cement milk, and stirring and mixing cement milk and earth and sand, the soil discharging blade 3 is used at the time of soil discharging operation. After excavating the earth and sand by rotating the rotary shaft 1 in the state of being attached to the stirring blade 2, the rotation is stopped and the rotary shaft 1 is pulled up, and the excavated earth and sand is discharged to the ground. For this reason, it is preferable that the soil discharging blade 3 has a large area within a range that does not hinder the work. As shown in FIG. 1 (b), the earth removing blade 3 is welded with a fitting steel material 4 obtained by processing lip groove type steel or a steel plate so as to match the cross-sectional shape of the stirring blade 2 on the lower surface thereof. Is attached to and removed from the stirring blade 2 via the fitting steel material 4 by fitting. Although FIG. 1 shows a pair of the two most advanced stirring blades 2, one of the most advanced stirring blades 2 is one.
When forming a pair, the soil discharge blades 3 are attached to each of the three blades.

With reference to FIG. 2, the relation between the attachment / detachment of the soil discharging blade 3 to / from the hole agitator of the present invention and the construction procedure of the soil cement pile construction method will be described.

This is an example of constructing a relatively short soil cement pile having a length of several m to 10 m by performing injection of cement milk in two equal portions.

(1) Work with the soil removal blade 3 attached to the rotary shaft 1.

After starting excavation from the surface of the earth and excavating for several tens of cm to 1 m, the rotary shaft 1 is pulled up and the excavated soil is discharged. The volume of excavated soil discharged corresponds to the volume increase due to the first injection and stirring of cement milk. (Fig. 2
(A)) (2) Work with the soil removal blade 3 removed from the rotary shaft 1.

[0016] The first injection of cement milk is started from the time when the inside of the drilled hole is further excavated and several tens of cm to 1.5 m are excavated. (Fig. 2 (b)) (3) Work with the soil removal blade 3 removed from the rotary shaft 1 (continuation of (2)).

Cement milk is injected and excavated soil is stirred while excavating to a predetermined depth, and then the rotary shaft 1 is pulled up. Due to the injection of cement milk, the earth and sand in the drilled holes have risen. (Fig. 2 (c)) (4) Work in a state in which the soil removal blade 3 is attached to the rotary shaft 1.

As in the case of (1), the raised sand is tens of cm
After excavating about 1 m, the rotary shaft 1 is pulled up and excavated soil is discharged. The volume of excavated soil discharged corresponds to the volume increase due to the second injection and stirring of cement milk. (Fig. 2 (d)) (5) Work with the soil removal blade 3 removed from the rotary shaft 1.

The second injection of cement milk is started from the time when the inside of the drilled hole is excavated by several tens of cm. (Fig. 2
(E)) (6) Work with the soil removal blade 3 removed from the rotary shaft 1 (continuation of (5)).

After the cement milk is injected to the deepest part and the excavated soil is stirred, the rotary shaft 1 is pulled up. Due to the injection of cement milk, the earth and sand in the drilled holes have risen. (Fig. 2
(F)) With the above, the construction of one soil cement pile using the drilling stirrer of the present invention is completed. (1) to (6) are repeated to create a large number of soil cement piles.

If there are variations in the height of each pile head, it will hinder the underground beam construction work to be installed on the pile head. Therefore, the pile 8 is removed by removing the earth and sand 8 above the pile head. I do.

In the example of FIG. 2, the injection of cement milk was divided into two times so as to sufficiently mix soil and cement milk to create a high quality soil cement pile, but the whole amount of cement milk was injected once without dividing. May be injected. In that case, the amount of excavated soil corresponding to the total amount of cement milk was discharged in (1) above, and in (2) above, the amount of cement milk was excavated from the time of excavation for the height of the earth and sand left on the pile head at the end. Start infusion.

The amount of earth and sand discharged prior to the injection of cement milk and the starting point of the injection of cement milk are based on the condition of the target ground, the injection amount of cement milk, the pile head level of soil cement piles, etc. Need to be calculated in advance.

[0024]

Since the present invention is configured as described above, it has the following effects.

(1) The work of constructing soil cement piles with one machine by the simple operation of attaching and detaching the soil discharge blades,
Can perform earth removal work.

(2) By using the hole agitator of the present invention, a soil cement pile can be constructed by a simple operation without discharging cement milk or cement-containing soil which may cause hard environment pollution. It will be possible.

[Brief description of drawings]

FIG. 1 is a view showing a tip end part of a hole agitator of the present invention,
(A) is a perspective view when the soil removal blade is attached, (b) is a side view when the soil removal blade is attached, and (c) is a bottom view of the soil removal blade.

FIG. 2 is a vertical cross-sectional view showing a process of a construction example of constructing a soil cement pile using the hole agitator of the present invention.

[Explanation of symbols]

1 ... Rotation axis, 2 ... Stirring blade, 3 ... Soil removal blade, 4 ...
・ Steel for fitting, 5 ・ ・ Drilling blade, 6 ・ ・ Drilling blade mounting blade,
7 ... Soil cement, 8 ... excavated soil.

Claims (1)

[Claims] 1. A stirring blade at the tip of a rotating shaft,
A drilling agitator for the soil cement pile construction method, in which a large area soil removal blade is detachably attached.