NO-VIBRATION AND NO-NOISE COMPACTION SAND PILE FORMATION METHOD

摘要

PURPOSE: To use a spiral blade attached to the outer peripheral surface of a casing not for assisting intrusion of the casing, but for improving the ground compaction effect. ;CONSTITUTION: Both penetration and pulling of a casing 3 with a spiral blade 9 are performed, for example, by a rack and pinion casing elevating device 7 in which while the casing 3 is rotated in the opposite direction to the direction of the spiral blade 9, the reaction force from a leader 2 can be obtained. It is preferable that the penetration is assisted by a drilling bit 10 of the tip of the casing 3. Thus, at the time of the penetration, the ground earth is not discharged to the ground, but pressed downward so that the ground compaction effect can be improved.;COPYRIGHT: (C)1996,JPO