JPS593602B2 - Ground improvement method and device using cycloidal hardener jet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ground improvement method using a jet of hardening material ejected in a cycloidal manner. A ground improvement method in which the hardening material is force-fed while being rotated through a rotary plate with a hole in it, and is injected from an injection nozzle.The flow of this jet stream is made into a cycloid and the hardening material is stirred and mixed with the ground surface. I will provide a.

Conventionally, methods known for improving the ground using a jet of hardening material spray hardening material horizontally at high speed from a special device attached to the tip of a rod, and use this jet to improve the ground. There are methods of cutting, stirring and mixing the ground and hardening material, rotating the rod, raising and lowering it to create a disk-shaped improved solid body or a wall-shaped improved solid body, and raising or rotating the rod while rotating. There was a method of descending while creating a cylindrical improvement layer.

However, in the above-mentioned method, the injection trajectories do not intersect even when the material collapses, and the layered structure is constantly improved, and it is not possible to sufficiently stir the ground and mix the hardening material and the ground.

For example, in the case of cohesive soil, there are many cases where the original ground surface of the fist dog remains inside the improved body, or the cut part is crushed without forming a cut surface due to the viscous fluidization of the cohesive soil. Ta.

In addition, in the case of sandy soil, it was often seen that disk-shaped improved bodies were piled up in layers, even though the rod should have been rotated and pulled out to create cylindrical improved bodies.

The present invention deals with this problem in view of such drawbacks. Namely, the present invention has a cycloidal injection trajectory in which the injection position of the high-speed jet is rotated, and the jets are crossed to completely stir and mix. The purpose is to

The ground improvement method using a hardening material jet according to the present invention will be explained in detail below.

1 is an injection rod which can be rotated and moved up and down by a drive device 2;

A tip device 3 is attached to the tip of the rod 1, and a swivel 4 is attached to the upper end, and the swivel 4 is connected to a high pressure pump via a hose 5, and the hardening material is injected from the high pressure pump via the hose 5 from the swivel 4 to the injection rod. It is being fed under pressure.

The tip device 3 is provided with four parts 6, and a rotary disc 8 having an injection nozzle 7 at the peripheral edge of the shaft supported in the recessed part is connected to the rod 1 and pivotally supported by a shaft 9, and this rotary disc 8 is supported by appropriate means such as The rotary disk rod 1 is provided with blades, the nozzle 7 is angled, etc., and high-pressure hardening material is used to enable rotation.

The injection direction of the rotary disc nozzle is not limited to this, but any direction that has a certain angle with respect to the rod may be used.

A drilling blade is provided at the tip of the rod 1, and the rod is rotated and lowered to insert it to a predetermined depth. Alternatively, the rod is previously excavated by poling, etc., and the rod is inserted into the hole, and then hardened material is poured into the hole using a high-pressure pump. 4 into the rod 1, and then sprayed from the nozzle 7 at high speed in the lateral direction while rotating the rotary disk 8 using the flow force of the hardened material.

At this time, the ground is cut and the hardening material is stirred and mixed on the ground.

It goes without saying that the rotation of the rotary disk 8 may be driven by a separate power source such as a motor.

At this time, the hardening material crosses the soil while drawing a cycloidal trajectory and is completely stirred and mixed with the hardening material on the ground, and the rod 1 is rotated and raised to create an improved solidified body.

Since the present invention is constructed as described above, the perforation jet is not planar, but the curing agent is mixed in while stirring the soil particles in a cycloidal manner, so that the wide jet trajectories are cross-coupled.
A hardened layer with a unique stirring structure is created, making it possible to obtain a tougher and improved consolidated body that could not be obtained with conventional planar drilling jets.

[Brief explanation of drawings]

The drawings show an embodiment of the apparatus used in the ground improvement method using high-speed jets according to the present invention, in which Fig. 1 is a vertical cross section during wall construction, and Fig. 2 is a plane taken along line XX in Fig. 1. Figure 3 is a vertical cross-sectional view when the cylindrical body is being constructed, Figure 4 is a plan view along the Y-Y line in Figure 3, Figure 5 is a vertical cross-sectional view when the cylindrical body is being constructed, and Figure 6 is the 5th cross-sectional view when the cylindrical body is being constructed.
Fig. 7 is a front view of the rod tip device, Fig. 8 is a vertical sectional view taken along W-W in Fig. 7, and Fig. 9 is a sectional view taken along V-V in Fig. 8. be. 1... Injection rod, 2... Drive device,
3... Tip device, 4... Swivel, 5
...Hose, 6...Recess, 7...
...Injection nozzle, 8...Rotary plate, 9...
·shaft.

Claims (1)

[Scope of Claims] 1. An injection rod, in which a rotary disk with 11 or more injection nozzles at the peripheral edge is rotatably supported on the side wall of the rod tip, is inserted to a predetermined depth in the target ground, and the hardening material is poured into the injection rod. This hardening material is pumped into the interior of the building, and is injected from an injection nozzle bored into a rotary disk with a shaft supported at the tip while rotating the rotary disk, and is injected in a cycloidal manner by rotating the injection position of the jet stream. A ground improvement method that improves the ground using water jets. 21 or a plurality of injection nozzles are installed by supporting an injection rod, in which a rotary disk provided at the peripheral edge is rotatably supported on the side wall of the tip end of the rod, by a driving device that provides vertical movement or rotational vertical movement. A soil improvement device in which the upper end of the rod is connected via a swivel to a pressure hose that connects to the hardening material tank.