Lateral displacement pier

• US 20020009337A1
• Filed: 06/15/2001
• Published: 01/24/2002
• Est. Priority Date: 06/15/2000
• Status: Active Grant

• Current Assignee: Geotechnical Reinforcement Company, Inc. (Commercial Metals Company)
• Original Assignee: Geotechnical Reinforcement Company, Inc. (Commercial Metals Company)
• Inventors: Fox, Nathaniel S., Peterson, Gale M.
• Granted Patent: US 6,425,713 B2
• Time in Patent Office: Days
• US Class Current: 405/232
• CPC Class Codes: E02D 3/08 by inserting stones or lost bodies, e.g. compaction piles sand drains for soil compaction E02D3/10; stressing soil while forming foundations E02D27/28
• CPC Class Codes: E02D 5/385 with removal of the outer mould-pipes documents also covered by one or several of the groups E02D5/40 - E02D5/44 are classified in all the relevant groups
• CPC Class Codes: E02D 5/44 with enlarged footing or enlargements at the bottom of the pile
• CPC Class Codes: E02D 5/46 making in situ by forcing bonding agents into gravel fillings or the soil consolidating soil in general E02D3/12
• CPC Class Codes: E02D 5/72 Pile shoes
• CPC Class Codes: E02D 7/20 Placing by pressure or pulling power

Abstract

A method and special mechanical apparatus for installation of support pier for structure comprises positioning a hollow tube apparatus in a soil matrix wherein the hollow tube apparatus has a hollow core and is susceptible to lateral and longitudinal movement, removing soil from the hollow core and then filling that core with an aggregate followed by raising and lowering of the hollow tube apparatus by means of a special bottom mechanical device in a manner which compacts the aggregate and also applies lateral forces to the aggregate against the walls of the cavity in the soil matrix, pushing a portion of the aggregate into the soil matrix.

Claims

1. A method for installation of a pier comprising, in combination, the steps of:

a) positioning a hollow tube apparatus having a longitudinal dimension and a lateral dimension in a soil matrix, said hollow tube apparatus including a hollow core and a special mechanical device lower end for directing both lateral and longitudinal forces when raised and lowered and reciprocated longitudinally in said soil matrix;

b) removing the soil matrix from the hollow core of the hollow tube apparatus;

c) at least partially filling the hollow tube apparatus with aggregate; and

d) raising and lowering the hollow tube apparatus incrementally to impart lateral forces on the aggregate and soil matrix simultaneously with longitudinal forces on the aggregate to thereby form compacted lifts as the casing is removed in incremental steps from the soil matrix.

2. The method of claim 1 wherein the step of filling the hollow tube apparatus comprises filling with a material selected from the group consisting of aggregate and dry cement, aggregate and recycled concrete, recycled concrete, recycled asphalt, aggregate and chemical additives, stone;

drainage graded stone, stone and sand, aggregate and mesh and combinations thereof.

3. The method of claim 1 including the further step of positioning a mechanical device in the hollow core of the hollow tube apparatus before placing aggregate in the casing.

4. The method of claim 3 wherein the mechanical device placed in the hollow tube apparatus extends the longitudinal length of the casing.

5. The method of claim 3 including the step of moving the mechanical device in the aggregate to densify the aggregate.

6. The method of claim 5 including the steps of removing the mechanical device from the hollow tube apparatus.

7. The method of claim 1 wherein the hollow tube apparatus is positioned in a predrilled cavity.

8. The method of claim 1 wherein the hollow tube apparatus is driven or pushed into the soil matrix.

9. The method of claim 1 wherein the hollow tube apparatus includes a mechanical portion with a lower peripheral surface defining an angle intermediate the longitudinal and lateral directions.

10. The method of claim 1 wherein removal of the soil matrix from the hollow tube apparatus is by drilling.

11. The method of claim 1 wherein removal of the soil matrix from the hollow tube apparatus is effected by excavating, by vacuum suction, combinations thereof or other means.

12. The method of claim 1 including vibrating the hollow tube apparatus.

13. The method of claim 1 including raising and lowering the hollow tube apparatus incrementally and lowering the hollow tube apparatus to impart forces on the soil matrix and aggregate.

14. A pier formed by the process of claim 1 or 3.

15. The method of claim 1 wherein the hollow tube apparatus is formed with an inwardly beveled lower edge end comprising a special mechanical device.

16. The method of claim 1 wherein the hollow tube apparatus is cylindrical.

17. The method of claim 1 wherein the hollow tube apparatus includes a uniform diameter hollow core, and a bottom mechanical device with an internal rim at the bottom of the hollow tube apparatus, said bottom mechanical device being beveled inwardly.

18. The method of claim 1 wherein the completed or partially completed aggregate pier may be preloaded to form a stiffer pier and to prestress and prestrain the matrix soil in the vicinity of the formed aggregate pier.

20. The apparatus of claim 18 further including a shaped rod member for placement in the hollow tube upon removal of the auger, and means for vibrating the rod member and incrementally lifting the tube and the rod member in discrete steps.

19. Apparatus for formation of an aggregate material pier in a soil matrix comprising, in combination:

(a) a hollow, elongate tube for generally vertical insertion into the soil matrix, said elongate tube including an open top end and an open bottom end, and a generally constant cross section hollow passage between the bottom and the top end, said bottom end having a reduced cross section and comprising a shaped rim for providing longitudinal and lateral forces simultaneously on the soil matrix as the tube is moved up and down longitudinally in the soil matrix; and

(b) an auger for placement in the tube to remove soil matrix from the tube, said auger sized to fit through the bottom end of the tube.