GROUND IMPROVING CONSTRUCTION METHOD AND EXCAVATING DEVICE THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a ground improving construction method capable of improving the ground by tightening and fixing charged sand and charged crushed stones without causing obstruction in peripheral ground and an effective excavating device used in the construction method. SOLUTION: A casing 10 in which a excavating blade and a excavating guide connected with it are spirally provided in an outer peripheral part in a preceding required section and a pile formation material introduction guide 13 is spirally provided in an inner peripheral part therein is used. Augers 2 are combined in the casing to drive them individually and drill a hole by the casing and the augers. The augers are inserted down to an excavating tip part in the casing, and a pile formation material C is charged into the casing. The augers are at least rotated reversely to push the charging pile formation material C in toward a pile bottom, the reverse rotation of the augers and the casing is maintained, the repetition of passing into and pulling out is repeated, and the pile formation material C is pressed against the ground A to pull up machinery and the materials and form a pile P.