CONSTRUCTION METHOD FOR ROOT HARDENED PART OF PILE HOLE, DIGGING METHOD FOR PILE HOLE, CONSTRUCTION DEVICE FOR ROOT HARDENED PART, AND DIGGING HEAD

摘要

PROBLEM TO BE SOLVED: To construct a foundation pile having good quality in a short time by forming pile hole digging and root hardened layer/pile periphery fixing liquid layer efficiently.;SOLUTION: An axis part 22 and a bottom enlarged part 23 of a pile hole 21 are digged by a digging head 1 from the ground surface 20 (a), (b). Various digging liquids are supplied in the vertical direction 32 from a first discharge port 6 and in the horizontal direction 33 from a second discharge port 7 to supply digging liquids to parts in the vicinity of cutter tips 5a, 11a of digging cutting edges 5, 11. Next, root hardening liquid is injected in the vertical direction 32 from the first discharge port 6 and in the horizontal direction 33 from the second discharge port 7 (c). The root hardening liquid is spreaded over a wide scope in the horizontal direction by injecting the foot protection liquid radially in the horizontal direction. Then, a digging rod 14 is pulled up while injecting pile periphery fixing liquid through the first discharge port 6 and the second discharge port 7 (d). Most of required amount of foot protection liquid is supplied through the first discharge port 6 to supply to a part around a pile hole wall through the second discharge port 7. Next, an existing pile 26 forming an annular rib 27 is caused to sink in the pile hole 21 and fix it (e).;COPYRIGHT: (C)2006,JPO&NCIPI