Method of and apparatus for soil stabilization

• US 4,606,675 A
• Filed: 01/16/1985
• Issued: 08/19/1986
• Est. Priority Date: 02/02/1984
• Status: Expired due to Term

• Current Assignee: Klaus Schmidt
• Original Assignee: Klaus Schmidt
• Inventors: Mitani, Takeshi, Aiko, Hideo
• Primary Examiner(s): Taylor, Dennis L.
• Application Number:
  US06/691,885
• Time in Patent Office: 580 Days
• Field of Search: 405/263, 405/269, 405/267, 405/266, 405/240, 405/241, 405/242, 166/50, 166/285, 166/292, 106/900, 106/95
• US Class Current: 405/263
• CPC Class Codes: E02D 3/126 and mixing by rotating blades

Abstract

Soft soil stratum is stabilized by jetting powdery agent into the ground and mixing and agitating the same with the soil, wherein a rotary shaft is inserted into the ground and a powdery stabilized agent carried by air is pneumatically transported by way of a transportation tube positioned within the rotary shaft and is jetted out from a nozzle disposed in communication with a blade which is integrally attached to and extended from the bottom end of the shaft, is mixed and is agitated for solidification with the soil by the rotation of the mixing blade, while the carrier air jetted into the ground is induced and discharged to the outside of the ground after separation and filtration. The state of the supply of the powdery stabilized agent is continuously optimally controlled in accordance with a predetermined set condition. The powdery stabilized agent can be transported smoothly and mixed with the soil uniformly to provide satisfactory soil stabilization, without repair and maintenance problems.

Claims

1. A method of soil stabilization by jetting the powdery stabilizing agent into the ground and mixing and agitating the same with the soil and utilizing compressed air, a transportation tube, a rotary shaft having a mixing blade integrally attached to and extending from a base of said shaft and a nozzle in communication with said blade, which comprises:

inserting a rotary shaft into the ground;

pneumatically feeding the powdery stabilizing agent from above the ground at a constant rate together with said compressed air by way of said transportation tube positioned within the rotary shaft;

jetting out the powdery stabilizing agent and the compressed air from said nozzle in communication with the mixing blade;

mixing and agitating the powdery stabilizing agent with the underground soil by rotation of the mixing blade to thereby solidifcate said agent and said soil;

inducing the carrier air jetted through the ground and then discharging the air outside the ground after filtration of said air; and

controlling the supply of the powdery stabilizing agent in accordance with a predetermined condition.

2. The method of soil stabilization by jetting the powdery stabilizing agent into the ground as defined in claim 1, which further comprises supplying the powdery stabilizing agent with a constant volume and/or weight and transporting the powdery stabilizing agent pneumatically under the effect of the compressed air.

3. The method of soil stabilization by jetting the powdery stabilizing agent into the ground as defined in claim 1, which further comprises jetting the compressed air to a gap formed between the rotary shaft and the ground upon insertion of the rotary shaft into the ground.

4. The method of soil stabilization by jetting the powdery stabilizing agent into the ground as defined in claim 1, which further comprises dissipating the compressed air jetted in the ground through a gap between the rotary shaft and the ground to a location above the ground.

5. The method of soil stabilization by jetting the powdery stabilizing agent into the ground as defined in claim 4, which further comprises separating the compressed air so dissipated from the powdery stabilizing agent and then discharging said compressed air to the atmosphere.

6. An apparatus for soil stabilized by jetting powdery stabilizing aagent into the ground, comprising:

a powder supply device disposed on the ground and having a constant volume and/or weight discharge mechanism;

a rotary shaft having a transportation tube formed inside thereof, which is connected by means of a swivel joint to said constant volume and/or weight mechanism wherein, said rotary shaft further comprises a mixing blade disposed with a nozzle in communication with the transportation tube connected to the swivel joint and an exhaustion guide for inducing a carrier gas to outside of the ground, and a control device for controlling the operation of the constant volume and/or weight. discharge mechanism and the elevation of the rotary shaft.

7. The apparatus for soil stabilization by jetting the powdery stabilized agent into the ground as defined in claim 6, wherein the nozzle is disposed at a position with respect to the mixing blade at a position free from the effect of the soil pressure exerted against said blade in the rotational direction.

8. The apparatus for soil stabilization by jetting the powdery stabilized agent into the ground as defined in claim 6, wheren said mixing blade further comprises a mixing blade expansible and shrinkable by a predetermined stroke in a rotational direction thereof.

9. The apparatus for soil stabilization by jetting the powdery stabilized agent into the ground as defined in claim 6, wherein said rotary shaft further comprises an exhaust guide for the carrier gas formed along a cicumference thereof.

10. The apparatus for soil stabilization by jetting the powdery stabilized agent into the ground as defined in claim 6, wherein said powder separation device further comprises powder sucking means.

11. The apparatus for soil stabilization by jetting the powdery stabilized agent into the ground as defined in claim 6, further comprising an additional mixing blade and a radially expansible and shrinkable mechanism for connecting said additional mixing blade to said rotary shaft.