Title:
METHOD AND DEVICE FOR BORING FOUNDATION GROUND
Document Type and Number:
Japanese Patent JP2610555
Kind Code:
B2
Abstract:
PURPOSE: To bore very easily and certainly a hole for driving a foundation pile having a sturdy compacted circumferential wall surface, which is free from risk of earth fall or collapse under the ground when a foundation ground for construction is to be prepared, and eliminate earth lifting entirely.
CONSTITUTION: An auger rod 3 having a conically inclining surface 5 and a precedingly excavating cutter 4 is installed in continuity below a casing 1 where. gradual/steep pressure earth curved surfaces 2 are alternately provided on the column surface in such a way as differing over and under relative to the axial direction. The earth from excavation to be made while the tip earth is rotarily excavated by the preceding cutter 4 is compacted to the circumferential wall surface of the hole through the compacting action and spreading due to the conically inclining surface 5. At the same time, the surplus earth of excavation is further compacted to the circumferential wall surface of the hole through the rotational action of the curved surfaces differing over and under of the gradual/steep pressure earth curved surface 2 of the casing 1 in pursuit of the auger rod 3. Thereby the hole is excavated for pile having a sturdy compacted wall surface under the ground.
Inventors:
Teruo Oi
Application Number:
JP35717791A
Publication Date:
May 14, 1997
Filing Date:
December 24, 1991
Export Citation:
Assignee:
Geo Top Co., Ltd.
International Classes:
E21B7/00; E21B7/26; E21B10/44; (IPC1-7): E21B7/00; E21B7/26
Attorney, Agent or Firm:
Hiromichi Kuroda (3 outside)