JPH0730551B2 - Control method of finished pile diameter in consolidation pile construction. - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the diameter of a finished pile when a solidified pile is formed in the ground by using a high-pressure jet jet and mechanical stirring together.

[0002]

2. Description of the Related Art A method of forming a solidified pile in the ground to improve the ground by using a high-pressure jet jet and mechanical stirring together is known.

In such a construction method, a high-pressure jet jet is not directly jetted from a pipe inserted into the ground, but a plurality of stirring blades centering on the pipe are provided, and a low-pressure hardening material is discharged from the vicinity of the center of the pipe. The stirring at a certain distance from the pipe is performed by mechanical stirring, and a high-pressure jet of water or a hardening material is further sprayed from the tip or the middle of the stirring blade to form a solidified pile, that is, a circular pile.

[0004]

In the above-mentioned construction method, a circular tubular construction pile having a predetermined thickness is added to the outside of the pile formed by the stirring blades, but the predetermined thickness can be selected according to the situation. Is desirable. Therefore, it is necessary to control the reaching distance of the jet jet.

By the way, when a high-pressure jet jet is injected into the ground, the reach of the jet jet is different depending on the soil quality and soil properties (strength, water content ratio, void ratio), so that water or hardener is conventionally used with excessive power. There was a tendency to give priority to securing a large finished diameter of the formed pile after injection. Therefore, there are problems such as loss of material and outflow of a large amount of slime.

The present invention makes it possible to easily control the reaching distance of the jet jet and to select a predetermined thickness of the building pile depending on the situation, so that the disadvantages such as the loss of material in the case of the conventional method can be avoided. It was made to solve.

[0007]

Therefore, according to the present invention, when a solidified pile is formed in the ground by using a high pressure jet jet and mechanical agitation in combination, it is inserted into the ground as a nozzle for injecting water or a hardening material. At least two nozzles provided on the stirring blades attached to the pipe to be separated at appropriate intervals in the longitudinal direction are used, and these nozzles are capable of adjusting the injection angle, and the nozzles can be adjusted according to the reaching distance. Adjust the injection angle to establish a cross jet, and thus control the diameter of the finished pile.

[0008]

It is known that when fluids ejected from two or more jet outlets meet each other, the energy of the combined jet decreases depending on the intersection angle. By applying this, the reaching distance of the synthesized jet flow is controlled to obtain a predetermined finished pile diameter.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

In the figure, 1 is a generator, 2 is a high-pressure pump driven by the generator 1, 3 is a pipe, 4 is a swivel joint connecting pipes inserted in the ground to the pipe 3, and 5 is a stirrer. Processing machine, 6 is a pipe inserted into the ground, 7
a, 7b, 7c are stirring blades provided in the tube 6 in several stages at intervals in the longitudinal direction, and 8a, 8b, 8c are stirring blades 7a, 7c.
nozzles 8a, 8b, 8
In c, the injection angle can be adjusted. Nozzle 8
a and 8b are adjacent stirring blades 7 as shown in FIG.
The nozzles 8a and 7b can also be provided as shown in FIG.
It is also possible to provide the a and 8c on the parallel stirring blades 7a and 7c.

Nozzle 8 provided on stirring blades 7a, 7b, (7c) from high-pressure pump 2 through swivel joint 4.
Water or a hardening material is sprayed from a, 8b, and (8c). Here, it is assumed that a hardening material is injected, and examples of the hardening material include cement milk, mortar, and chemicals. The nozzles 8a, 8b, (8c) have adjustable angles, and the angles of the nozzles 8a, 8b, (8c) are set so that the cross jet S is established (to meet). Further, as the intersection angle α, an angle corresponding to the reaching distance is determined in advance and set to that angle.

The jetting timing of the jet flow is determined according to the working condition at that time, and may be jetted when the pipe 6 penetrates or when the pipe 6 is pulled out.

For mechanical stirring by the stirring blades 7a, 7b, 7c, for example, the stiffening material M is discharged at a low pressure from the vicinity of the tip of the pipe 6 to stir to form a stirring pile B-1. Further, when the pipe 6 rotates while spraying the hardening material from the nozzles 8a, 8b, (8c) at the same time and the position of the processing machine 5 moves in either the upper or lower direction, the intersection jet S meets as shown in the figure. The column-shaped construction pile B-2 having T as the outermost edge R is integrally finished in the ground A.

Further, the above-mentioned construction method is not limited to the chemical-charging pile construction method in which the hardening material is jetted from the nozzle, but water is jetted from the nozzle to cut the ground and the void is filled with the hardening material. It can also be applied to the jet grout method.

[0015]

EFFECTS OF THE INVENTION Conventionally, since there is no degree of freedom to control the finished diameter of the pile due to a fixed relationship with the jet flow rate, the nozzle cross-sectional area of the nozzle, etc., it is difficult to use the material efficiently, and the slime seepage amount is also suppressed. was difficult. By using the cross jet of the present invention, the finish diameter of the building pile adapted to the design can be freely selected by the angle of the nozzle in addition to the flow rate of the hardening material and the cross-sectional area of the discharge port. Moreover, the number of cross jets requires a plurality of jets to cross each other, but the number of jets cutting the soil per unit depth is increased by the number of jets, and the stirring efficiency is significantly increased.

[Brief description of drawings]

FIG. 1 is a view showing an apparatus for carrying out a method for controlling a diameter of a finished pile in forming a consolidated pile by a jet method according to the present invention.

FIG. 2 is a diagram showing a first example of an injection direction.

FIG. 3 is a diagram showing a second example of an ejection direction.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Generator 2 ... High-pressure pump 3 ... Piping 4 ... Swivel joint 5 ... Agitation processing machine 6 ... Pipes to be inserted into the ground 7a, 7b, 7c ... Agitation blades Nozzles 8a, 8b, 8c

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomohiro Isoda 2153-102, Norenokidai, 3273 Asahigaoka-cho, Hanamigawa-ku, Chiba-shi, Chiba (72) Akihiro Miyoshi 1758 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa ( 72) Inventor Koichiro Yamaguchi 3281 Kamibemi, Sowa-machi, Sarushima-gun, Ibaraki Prefecture

Claims (1)

[Claims] 1. As a nozzle for injecting water or a hardening agent when forming a solidified pile in the ground by using a combination of a high-pressure jet jet and mechanical agitation, an appropriate interval is provided in a pipe inserted into the ground in the longitudinal direction thereof. At least two nozzles provided on the stirring blades that are separately installed are used, and these nozzles have adjustable jet angles, and the jet angles of the nozzles are adjusted according to the reach distance to establish a cross jet flow. A method for controlling a pile diameter in a consolidated pile construction by using a mechanical agitation and a jet method together, which is characterized by controlling a finished diameter.