Ground Anchor

• US 20080302028A1
• Filed: 09/20/2006
• Published: 12/11/2008
• Est. Priority Date: 09/20/2005
• Status: Abandoned Application

• Current Assignee: Stephen Mark Lewenhoff
• Original Assignee: Stephen Mark Lewenhoff
• Inventors: Lewenhoff, Stephen Mark
• Application Number:
  US12/067,529
• Publication Number:
  US 20080302028A1
• Time in Patent Office: Days
• US Class Current: 52/157
• CPC Class Codes: E02D 5/80 Ground anchors for galleries, tunnels or shafts E21D21/00
• CPC Class Codes: E02D 5/801 driven by screwing
• CPC Class Codes: E02D 7/22 Placing by screwing down screw piles per se E02D5/56
• CPC Class Codes: E04H 12/2223 by screwing

Abstract

A ground anchor (10) comprising an anchor shaft (11) and an anchoring screw (13) moulded onto the anchoring shaft adjacent the lower end thereof. The anchoring shaft (11) is of a rectangular cross-section with four side walls (12). The anchoring shaft (11) is configured at its bottom end (15) for ground penetration. The upper end (19) of the anchor shaft (11) is configured to receive torque applied thereto. The anchoring screw (13) comprises a hub (21) and a screw flight (23) on the hub. The anchoring screw (13) is moulded onto the anchor shaft (11), and the hub (21) is keyed to the anchor shaft. The anchoring screw (13) is so constructed that the spiral flight (23) is rigid yet has some resilient flexibility which allows the flight to deflect laterally in the direction of the screw axis. Specifically, the screw flight (23) has sufficient rigidity to allow it to penetrate the ground in which it is intended to be used when torque is applied to the anchor shaft (11). Further, the screw flight (23) has sufficient rigidity in order to retain the ground anchor (10) embedded in the ground when subjected to the normal load conditions for which it is intended, as is the case with conventional ground anchors. The resilient flexibility provides the screw flight (23) with a degree of ‘springiness’, so allowing the screw flight (23) to deflect laterally in the direction of the screw axis when subjected to the loadings to which it is exposed when winding into the ground. With this arrangement, the pitch of the helical screw (25) is permitted to alter during ground embedment as ground pressure increases.

Claims

1. A ground anchor comprising an anchoring screw, the anchoring screw comprising a screw flight winding about a screw axis, the screw flight being generally rigid with some lateral resilient flexibility.

2. A ground anchor according to claim 1 wherein the screw flight is formed from a moulded non-metallic material.

3. A ground anchor according to claim 2 wherein the screw flight is formed of a composite plastics material.

4. A ground anchor according to claim 1, wherein the screw flight is supported on a hub.

5. A ground anchor according to claim 4 wherein the screw flight is formed integrally with the hub.

6. A ground anchor according to claim 5 wherein the anchoring screw is moulded from a composite plastics material.

7. A ground anchor according to claim 1 further comprising an anchor shaft on to which the anchoring screw is mounted.

8. A ground anchor according to claim 7 wherein the anchoring screw is moulded onto the anchoring shaft.

9. A ground anchor according to claim 8 wherein the anchoring shaft is configured for keying the moulded anchoring screw onto the shaft.

10. A ground anchor according to claim 7, wherein the anchoring shaft is or a polygonal cross-section, such as hexagonal or rectangular cross-section.

11. A ground anchor according to claim 7 wherein the anchor shaft has a foot end configured for ground penetration.

12. A ground anchor according to claim 7 wherein the anchor shaft has a head end adapted to receive torque to drive the anchor into the ground.

13. A ground anchor according to claim 12 wherein the head end of the anchor shaft incorporates at least one drive hole located through the side of the shaft.

14. A ground anchor according to claim 1 wherein the screw flight is adapted for selective variation of the circumference thereof.

15. A ground anchor according to claim 14 wherein the screw flight is adapted to be cut to vary the circumference thereof.

16. A ground anchor according to claim 15 wherein the screw flight incorporates a guide marking radially inwardly of the outer periphery thereof.

17. A ground anchor comprising an anchor shaft and an anchoring screw on the anchor shaft, the anchoring screw comprising a screw flight winding about a screw axis, the screw flight being generally rigid with some lateral resilient flexibility.

18. A ground anchor according to claim 17 further comprising a lateral stabilisation device adapted to be fitted onto the anchor shaft and to engage the ground to provide lateral stabilisation to the shaft within the ground.

19. A ground anchor according to claim 18 wherein the lateral stabilisation device comprises a body adapted to be fitted onto the anchor shaft for engagement with the ground to provide lateral support for the anchor shaft with respect to the ground.

20. A ground anchor according to claim 19 wherein the body is adapted to be rotatably supported on the shaft.

21. A ground anchor according to claim 20 wherein the body incorporates a bearing surface and the anchor shaft is provided with an abutment for engaging against the bearing surface for urging the body into engagement with the ground as the ground anchor is embedded into the ground.

22. A ground anchor according to claim 21 wherein the bearing surface is defined by a thrust bearing in the body.

23. A ground anchor according to claim 21 wherein the abutment provided on the anchor shaft comprises a pin projecting from the shaft.

24. A ground anchor according to claim 19 wherein the body comprises one or more lateral projections presenting surfaces for engagement with the ground.

25. A ground anchor according to claim 24 wherein the lateral projections are configured as vanes.

26. A ground anchor according to claim 25 wherein there are four vanes arranged in an X formation when viewed in plan.

27. A ground anchor according to claim 25 wherein each vane is configured at the lower end thereof for penetration with the ground.

28. A ground anchor according to claim 19 wherein the body further comprises a sleeve section defining a central passage for rotatably receiving the anchoring shaft.

29. A ground anchor according to claim 19 wherein the body comprises a plurality of body sections.

30. A ground anchor according to claim 19 wherein the body incorporates a recess for accommodating the upper end of the anchor shaft, the recess being configured to facilitate access to the upper end of the anchor shaft when accommodated in the recess.

31. A method of manufacturing a ground anchor, the method comprising providing an anchor shaft and moulding an anchoring screw onto the anchor shaft.

32. A method according to claim 31 farther comprising configuring the shaft for keying the moulded anchoring screw onto the anchor shaft.

33. A lateral stabilisation device for a ground anchor having an anchor shaft, the lateral stabilisation device comprising a body adapted to be fitted onto the anchor shaft for engagement with the ground to provide lateral support for the anchor shaft with respect to the ground.

34. A lateral stabilisation device according to claim 33 wherein the body is adapted to be rotatably supported on the anchor shaft.

35. A lateral stabilisation device according to claim 34 wherein the body incorporates a bearing surface against which an abutment on the anchor shaft can engage for urging the body into engagement with the ground as the ground anchor is embedded into the ground.

36. A lateral stabilisation device according to claim 35 wherein the bearing surface is defined by a thrust bearing in the body.

37. A lateral stabilisation device according to claim 33 wherein the body comprises one or more lateral projections presenting surfaces for engagement with the ground.

38. A lateral stabilisation device according to claim 37 wherein the lateral projections are configured as vanes.

39. A lateral stabilisation device according to claim 38 wherein there are four vanes arranged in an X formation when viewed in plan.

40. A lateral stabilisation device according to claim 38 wherein each vane is configured at the lower end thereof for penetration with the ground.

41. A lateral stabilisation device according to claim 33 wherein the body further comprises a sleeve section defining a central passage for rotatably receiving the anchoring shaft.

42. A lateral stabilisation device according to claim 33 wherein the body comprises a plurality of body sections.

43. A lateral stabilisation device according to claim 33 wherein the body incorporates a recess for accommodating the upper end of the anchor shaft, the recess being configured to facilitate access to the upper end of the anchor shaft when accommodated in the recess.

44. (canceled)

45. A ground anchor comprising an anchor shaft, anchoring screw mounted on the anchor shaft, the anchoring screw comprising a screw flight winding about a screw axis, the screw flight being generally rigid with some lateral resilient flexibility, and a body adapted to be fitted onto the anchor shaft for engagement with the ground to provide lateral support for the anchor shaft with respect to the ground.

46. A ground anchor according to claim 45 wherein the body is adapted to be rotatably supported on the anchor shaft.

47. A ground anchor according to claim 46 wherein the body incorporates a bearing surface against which an abutment on the anchor shaft can engage for urging the body into engagement with the ground as the ground anchor is embedded into the ground.

48. A ground anchor device according to claim 47 wherein the bearing surface is defined by a thrust bearing in the body.

49. A ground anchor according to claim 45 wherein the body comprises one or more lateral projections presenting surfaces for engagement with the ground.

53. A ground anchor according to claim 45 wherein the body further comprises a sleeve section defining a central passage for rotatably receiving the anchoring shaft.

54. A lateral stabilisation device according to claim 45 wherein the body incorporates a recess being configured to facilitate access to the upper end of the anchor shaft when accommodated in the recess.

50. A ground anchor according to claim 50 wherein the lateral projections are configured as vanes.

51. A ground anchor according to claim 50 wherein there are four vanes arranged in an X formation when viewed in plan.

52. A ground anchor according to claim 50 wherein each vane is configured at the lower end thereof for penetration with the ground.

55-57. -57. (canceled)