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A tamper device including a shaft for driving a tamper head, and a shield. A tamper head is attached to the end of the shaft for tamping a lift of aggregate in a cavity formed in a ground surface. A shield attached to the tamper device and spaced a predetermined distance above a top surface of the t

A tamper device including a shaft for driving a tamper head, and a shield. A tamper head is attached to the end of the shaft for tamping a lift of aggregate in a cavity formed in a ground surface. A shield attached to the tamper device and spaced a predetermined distance above a top surface of the tamper head, the shield having a predetermined length extending upwardly above the tamper head sufficient to prevent sidewalls of a cavity in soft soil in which the tamper device is used from failing and collapsing into the cavity. Methods of constructing aggregate columns with thicker lifts are also disclosed.

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1. A tamper device in combination with a preformed generally cylindrical elongate cavity, the device comprising: a) a shaft for driving a tamper head;b) a tamper head attached at the end of the shaft for tamping a lift of aggregate in the generally cylindrical elongate cavity formed in a ground surf

1. A tamper device in combination with a preformed generally cylindrical elongate cavity, the device comprising: a) a shaft for driving a tamper head;b) a tamper head attached at the end of the shaft for tamping a lift of aggregate in the generally cylindrical elongate cavity formed in a ground surface, the tamper head having a generally flat, blunt bottom face; andc) a laterally immobile shield attached to the tamper device and spaced a predetermined distance above a top surface of the tamper head, and the shield having a predetermined length extending upwardly above the tamper head sufficient to prevent sidewalls of a cavity in soft soil in which the tamper device is used from failing and collapsing into the cavity. 2. The tamper device of claim 1, wherein the tamper head further comprises a tapered surface extending circumferentially from the bottom face to an edge thereof. 3. The tamper device of claim 2, wherein the tapered surface extends upwardly from the blunt bottom face at an angle of about 45 degrees. 4. The tamper device of claim 1, wherein the shield has a width substantially equal to the width of the tamper head. 5. The tamper device of claim 1, wherein the shield has a width greater than the width of the tamper head. 6. The tamper device of claim 1, wherein the shield has an opening for allowing passage of the shaft having the tamper head attached thereto. 7. The tamper device of claim 1, wherein the predetermined length of the shield is in the range of about 1.0 to about 2.5 times the tamper head diameter. 8. The tamper device of claim 1, wherein the width of the tamper head is in the range of about 12 to 36 inches. 9. The tamper device of claim 1, wherein the tamper head is shaped substantially circular. 10. The tamper device of claim 1, further comprising one or more attachment points for attaching the shield thereto. 11. The tamper device of claim 10, wherein the one or more attachment points comprise one or more bolt holes. 12. The tamper device of claim 10, wherein the shield further comprises attachment hardware for attaching the shield to the tamper device at the one or more attachment points. 13. The tamper device of claim 12, wherein the attachment hardware comprises one or more bolts. 14. The tamper device of claim 1, wherein the predetermined distance is a distance sufficient such that the shield does not interfere with operation of the tamper head. 15. The tamper device of claim 1, wherein the predetermined distance is in a range of greater than zero (0) to about four (4) inches. 16. The tamper device of claim 1, further comprising a flexible membrane attached to and extending downward from a bottom portion of the shield. 17. The tamper device of claim 16, wherein the flexible membrane extends downward to be in contact with the top surface of the tamper head. 18. The tamper device of claim 16, wherein the flexible membrane extends downward to be in close association with the top surface of the tamper head. 19. The tamper device of claim 16, wherein the flexible membrane is configured to prevent soil from intruding into an interior area of the shield. 20. The tamper device of claim 1, further comprising a collar attached to a top portion of the shield, wherein the collar is shaped and configured to reduce the opening at the top of the shield. 21. The tamper device of claim 20, wherein the collar functions to prevent soil from intruding into an interior area of the shield through the top portion of the shield. 22. The tamper device of claim 20, wherein the collar comprises a frusto-conical collar. 23. The tamper device of claim 1, wherein the shield comprises a hollow cylinder. 24. The tamper device of claim 23, wherein the hollow cylinder is filled with lightweight material. 25. The tamper device of claim 1, wherein the shield comprises a solid cylinder. 26. A method of constructing aggregate columns, comprising the steps of: a) preforming an elongate cavity in a ground surface, the cavity having a generally uniform cross-sectional area;b) placing a lift of aggregate into the cavity; andc) tamping the lift with a tamper device having a tamper head attached at the end of a shaft, the tamper head having a generally flat, blunt bottom face, and using a laterally immobile shield attached to the tamper device and spaced a predetermined distance above a top surface of the tamper head, and the shield having a predetermined length extending upwardly above the tamper head sufficient to prevent sidewalls of a cavity in soft soil in which the tamper device is used from failing and collapsing into the cavity. 27. The method of claim 26, wherein the tamper head further comprises a tapered surface extending circumferentially from the bottom face to an edge thereof. 28. The method of claim 27, wherein the tapered surface extends upwardly from the blunt bottom face at an angle of about 45 degrees. 29. The method of claim 26, wherein the shield has a width substantially equal to the width of the tamper head. 30. The method of claim 26, wherein the shield has a width greater than the width of the tamper head. 31. The method of claim 26, wherein the shield has an opening for allowing passage of the shaft having the tamper head attached thereto. 32. The method of claim 26, wherein the tamping is conducted by driving the tamper head with the shaft extending upwardly therefrom, the shield having a predetermined length extending upwardly above the tamper head sufficient to prevent the side walls of the elongate cavity from failing and collapsing into the cavity during tamping operations. 33. The method of claim 26, wherein the predetermined length of the shield is in the range of about 1.0 to about 2.5 times the tamper head diameter. 34. The method of claim 26, wherein the width of the tamper head is in the range of about 12 to 36 inches. 35. The method of claim 26, wherein the tamper head is shaped substantially circular. 36. The method of claim 26, wherein the thickness of the lift of aggregate is approximately equal to two to three times the distance across the cavity. 37. The method of claim 26, wherein the tamping is conducted in a cavity formed in soft soil. 38. The method of claim 26, wherein the shield comprises a hollow cylinder. 39. The method of claim 38, wherein the hollow cylinder is filled with a lightweight material. 40. The method of claim 26, wherein the shield comprises a solid cylinder. 41. The method of claim 26, wherein the tamper device further comprising one or more attachment points for attaching the shield thereto. 42. The method of claim 41, wherein the one or more attachment points comprise one or more bolt holes. 43. The method of claim 41, wherein the shield further comprises attachment hardware for attaching the shield to the tamper device at the one or more attachment points. 44. The method of claim 43, wherein the attachment hardware comprises one or more bolts. 45. The method of claim 26, wherein the predetermined distance is a distance sufficient such that the shield does not interfere with operation of the tamper head. 46. The method of claim 26, wherein the predetermined distance is in a range of greater than zero (0) to about four (4) inches. 47. The method of claim 26, wherein the shield further comprising a flexible membrane attached to, and extending downward from a bottom portion of the shield. 48. The method of claim 47, wherein the flexible membrane extends downward to be in contact with the top surface of the tamper head. 49. The method of claim 47, wherein the flexible membrane extends downward to be in close association with the top surface of the tamper head. 50. The method of claim 47, wherein the flexible membrane is configured to prevent soil from entering an interior area of the shield. 51. The method of claim 26, wherein the shield further comprising a collar attached to a top portion of the shield, wherein the collar is shaped and configured to reduce the opening at the top of the shield. 52. The method of claim 51, wherein the collar functions to prevent soil from intruding into an interior area of the shield through the top portion of the shield. 53. The method of claim 51, wherein the collar comprises a frusto-conical collar.