JPH0633451A - Excavation and agitation device in soil cement piling method - Google Patents

Abstract

PURPOSE:To manufacture an excellent quality soil cement pile by forcibly crushing excavated earth and sand to a satisfactory extent. CONSTITUTION:There are provided an excavation blade 2 whose size is proper to the size of a cement pile to be built on the lower end of an excavation and agitation shaft 1 to be rotated and a spirally-shaped agitation blade 3 which follows to the blade 2. An auxiliary mixing cylinder 4, which projects a spirally-shaped auxiliary agitation blade 42 in a similar manner to the mixing blade 3, is inserted into the outer periphery of the mixing blade 3 and forced to make a driven pivot motion. This construction makes it possible to forcibly crush and agitate and knead the excavated earth and sand.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drilling and stirring apparatus suitable for constructing soil cement piles.

[0002]

2. Description of the Related Art In civil engineering work and construction work, a low-vibration and low-noise cast-in-place pile construction method is widely used as a method for constructing a foundation pile while minimizing the influence on the surroundings. However, in this cast-in-place pile method, a large amount of highly water-containing mud as industrial waste is discharged during excavation, and this disposal requires labor and cost. Therefore, as a method of constructing desired piles by using the cast-in-place pile construction method with low vibration and low noise and without discharging industrial waste, steel materials are inserted into the cement cement piles before the cement hardens, and they are integrally constructed. The soil cement pile method has been proposed. And this earth cement pile construction method generally uses an earth auger or the like.

[0003]

In the conventional excavation method, an excavation blade is attached to the lower end, and a stirring blade is attached above this.
This is rotated to excavate a hole of a required diameter, and in the course of this excavation, cement milk is sequentially injected from the excavation blade portion into the excavated earth and sand and kneaded. Therefore, the cement milk is injected at the tip of the excavating stirring blade, which makes it difficult to perform uniform stirring. Moreover, some of the clay-based excavated soil is in the form of lumps, and since this lumped soil is not crushed, it cannot be mixed with cement milk,
Soil cementation is not complete.

According to the present invention, by controlling the rotation direction of the excavating blade and the stirring blade with the same axis, the lumpy earth and sand are crushed, and the cement milk is injected from the stirring blade surface to obtain the cement milk. The purpose is to ensure uniform stirring with a simple method.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above-mentioned object, and has an excavation blade having a diameter corresponding to the diameter of a soil cement column formed at the lower end of a rotationally driven excavation stirring shaft, This is equipped with a spiral stirring blade that follows this, and an auxiliary stirring cylinder formed by protruding a spiral auxiliary stirring blade similar to the stirring blade on the inner peripheral surface of the outer cylinder is inserted into the outer circumference of this stirring blade. , This auxiliary stirring cylinder is controlled and rotated with respect to the excavation stirring shaft,
The gist is that the excavated earth and sand are crushed and agitated and kneaded, and the cement milk is injected into this.

[0006]

[Operation] Since the excavation blade is provided at the lower end of the excavation stirring shaft, and the spiral stirring blade is provided on the outer periphery under the shaft, and the auxiliary stirring cylinder driven to be controlled and rotated is fitted on the outer periphery of the stirring blade, so that the block shape in the excavated soil The body is also crushed between the stirring blade / auxiliary stirring cylinder and both stirring blade surfaces,
Further, the earth and sand pressed against the cement milk injection hole passes through this hole to enhance the stirring efficiency and ensure reliable stirring. Further, since the cement milk is injected from the stirring blade surface, it can be uniformly mixed with the stirring earth and sand, and a homogeneous soil cement column can be reliably formed.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An excavation and agitation device in the soil cement pile construction method of the present invention will be described below with reference to the illustrated embodiments. In the figure, reference numeral 1 denotes an excavation stirring shaft having a required diameter, a drive device is provided at the upper end, and an excavation stirring blade is provided at the lower end, so that the excavation stirring shaft 1 is rotationally driven. And depending on the excavation depth, if the length is insufficient with the excavation stirring shaft of a predetermined length,
It can be added if necessary.

The excavating and stirring blade provided at the lower end of the excavating and stirring shaft 1 is composed of a pair of excavating blades 2 and a stirring blade 3, and the excavating blade 2 is projectingly provided at the lower end of the excavating and stirring shaft 1. The excavation blade 2 has a large number of excavation claws 22 projecting downward from the excavation blade main body 21 attached to the lower end of the excavation stirring shaft 1 at a required twist angle, and the excavation claws 22, 22 The excavation claws 22 are arranged in an array so as to have the pile diameter of the soil cement pile to be constructed and to enable uniform excavation.

The stirring blade 3 is provided at a position higher than the excavation blade 2 and further on the outer peripheral surface of the excavation stirring shaft 1 so as to project in a spiral shape with a required pitch, and the inside is hollow, and inside the stirring blade and the inside of the excavation stirring shaft 1. And a large number of cement milk injection holes H are formed in the stirring blade surface. The stirring blade 3 has an appropriate pitch and number of turns so that the earth and sand excavated by the excavation blade 2 can be stirred as desired.

An auxiliary stirring cylinder 4 is provided on the outer circumference of the stirring blade 3.
Is inserted. The auxiliary stirring cylinder 4 has an outer cylinder 41 having an outer diameter substantially matched to the diameter of the soil cement column to be formed,
The outer cylinder 41 is composed of a spiral auxiliary blade 42 protruding from the inner peripheral surface of the outer cylinder 41.

The outer cylinder 41 has the above-described outer diameter and a length such that the excavated soil is sufficiently agitated, and the spiral pitch and direction of the auxiliary blades 42 projecting from the inner peripheral surface of the outer cylinder 41 are The same as the stirring blade 3, a through hole having an inner diameter is formed in the central portion of the auxiliary blade 42 so that the excavation stirring shaft 1 can be inserted, and the surface of the auxiliary blade 42 is crushed as necessary. Drill holes for better kneading.

A case of constructing a soil cement column using the excavating and stirring apparatus configured as described above will be described below. When the excavation stirring shaft 1 is driven by the driving device at a predetermined rotational speed while being driven downward, the excavation blade 2 excavates, and the soil excavated by the excavation blade is successively spiraled by the entry of the excavation blade. The stirring blade 3 is stirred. At this time, since the auxiliary stirring cylinder 4 is inserted into the outer periphery of the stirring blade 3, the rotational force of the stirring blade 3 is driven by the spiral auxiliary blade 42 via the earth and sand in the outer cylinder 41 and is the same. In the direction, the rotation is made with a difference in rotation. For this reason, even if there is a lump of clay or the like in the excavated earth and sand, the auxiliary wing surface 42 and the stirring wing surface 3, which are driven to rotate, are slidably pressed and crushed, and the lump of clay is surely made into particles. Sediment passes through the cement milk injection hole on the blade surface to improve the kneading effect, and the cement milk injected from this hole is used for uniform mixing and stirring,
And kneaded to create the desired homogeneous soil cement column.

In this way, when the excavation blade 2 is excavating to the required depth, the auxiliary stirring cylinder 4 is driven to rotate and slides in the vertical direction of the shaft 1 to follow the desired stirring and crushing. Is to do. And after creating the desired soil cement pillar,
The excavation and agitation device is pulled up from the inside of the pillar, and a steel material having a required diameter is inserted and built before the soil cement is hardened to construct a desired pile.

FIGS. 6 and 7 show a second embodiment, which is similar to the first embodiment in that an auxiliary stirring cylinder having spiral auxiliary blades is fitted around the outer circumference of the excavation stirring shaft. is there.
However, in the first embodiment, the auxiliary stirring cylinder 4 is driven and rotated by the excavation stirring shaft 1, whereas in the second embodiment, the auxiliary stirring cylinder 4 is controlled and driven to forcibly rotate.

In the second embodiment, one or more guide grooves 5 are formed on the outer peripheral surface of the outer cylinder 41 along the longitudinal axis of the outer cylinder 41. Cylinder shaft 7
The engaging piece 61 of the guide arm 6 provided at the lower part of the above is slidably fitted and locked in the guide groove 5 to variably drive the outer cylinder shaft 7.

Although not shown in the drawings, the outer cylinder shaft 7 can be selectively driven in the same direction or in the opposite direction with respect to the excavation drive shaft 1 by a driving device, and its driving speed can be adjusted.

By controlling the rotation of the auxiliary stirring cylinder 4 via the guide arm 6 on the outer cylinder shaft 7 which is variably driven in this way, the lumped earth and sand are reliably crushed. That is, when both shafts are driven in the same direction and at different speeds, the auxiliary stirring cylinder rotates with a delay depending on the difference in rotation. As a result, the auxiliary stirring shaft moves in the longitudinal direction of the drive shaft according to the rotation difference. As a result, the massive earth and sand are opposed to each other, and are crushed between the wing surfaces adjacent to each other.

Then, as shown in FIG. 6, when the auxiliary stirring cylinder 4 reaches the maximum allowed position and the rotation difference between both blades and the sliding are stopped, the auxiliary stirring cylinder 4 is rotated in the reverse direction. , The auxiliary stirring cylinder is lowered to return to the original position as shown in FIG. Similar crushing is performed during this descent. This operation is sequentially repeated according to excavation.

[0019]

The excavating and stirring apparatus in the soil cement pile construction method of the present invention has auxiliary blades that are driven to rotate or follow the outer periphery of the stirring blades or that rotate at variable speeds, are concentrically arranged, and the auxiliary blades are stirred. Like the wings, it has a spiral shape,
The earth and sand excavated by the excavation blade at the lower end is crushed and stirred by both blades in the outer blade outer cylinder, so uniform stirring and kneading can be performed, and the lumps are surely crushed and injected from the stirring blade surface. It has the advantage that it can be mixed with cement milk uniformly and that a homogeneous soil cement column can be created with a simple device.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional front view showing an embodiment of an excavation stirring device in a soil cement pile method of the present invention.

FIG. 2 is a vertical cross-sectional view of an excavating stirring blade.

FIG. 3 is a vertical sectional view of an auxiliary stirring cylinder.

FIG. 4 is an explanatory diagram at the time of stirring.

FIG. 5 is an explanatory diagram when the same pressure crush stirring is performed.

FIG. 6 is a vertical sectional view of a second embodiment.

FIG. 7 is a vertical cross-sectional view showing a state where the auxiliary blade outer cylinder is pushed down by the reverse rotation.

[Explanation of symbols]

 1 Excavation stirring shaft 2 Excavation blade 3 Stirring blade 4 Auxiliary stirring cylinder 5 Guide groove 6 Guide arm 61 Engagement piece 7 Outer cylinder shaft

Claims (3)

[Claims] 1. An excavation blade having a diameter that matches a diameter of a soil cement column formed at a lower end of a rotationally driven excavation stirring shaft,
This is equipped with a spiral stirring blade that follows this, and an auxiliary stirring cylinder formed by protruding a spiral auxiliary stirring blade similar to the stirring blade on the inner peripheral surface of the outer cylinder is inserted into the outer circumference of this stirring blade. An excavating and agitating device in a soil cement pile construction method, characterized in that the excavated earth and sand are crushed and agitated and kneaded by being driven to rotate. 2. The excavating and agitating device in the soil cement pile method according to claim 1, wherein the agitating blade surface is provided with an injection hole for injecting cement milk into the excavating and agitating earth and sand. 3. An excavation blade having a diameter corresponding to the diameter of a soil cement column formed at the lower end of a rotationally driven excavation stirring shaft,
This is equipped with a spiral stirring blade that follows this, and an auxiliary stirring cylinder formed by protruding a spiral auxiliary stirring blade similar to the stirring blade on the inner peripheral surface of the outer cylinder is inserted into the outer circumference of this stirring blade. In addition, the auxiliary stirring cylinder is rotated concentrically with the excavation stirring shaft by a locking piece of a guide arm protruding from the lower end of the outer cylinder shaft which is variably driven, and the auxiliary stirring cylinder is rotated in the longitudinal direction of the excavation stirring shaft. Excavator and agitator in the soil cement pile construction method that is movably locked to the ground.