PRESS-IN METHOD AND DEVICE FOR CASING FOR USE IN ALL- CASING CONSTRUCTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide press-in techniques for a casing for use in an all-casing construction method, capable of pressing the casing into a great depth without digging irrespective of the soil condition of the ground. SOLUTION: This press-in device for a casing is used in an all-casing construction method wherein a vertical hole is drilled by use of a casing comprising an end casing C provided with an inner cutter C2' and an outer cutter 2", and a joint casing connected thereto. The end casing C is provided with an auxiliary cutter D for digging an inner peripheral area inside the end casing C inward of the inner cutter C2', and an inner peripheral fluid ejection pipe 11 having a nozzle 11C from which pressure fluid is ejected into an annular inner peripheral area dug by the auxiliary cutter D; the pressure fluid is ejected into the annular inner peripheral area dug by the auxiliary cutter D, so that the soil dug out of the area is plasticized and fluidized along an overall periphery near the inner peripheral surface of the lower part of the end casing C to reduce the resistance of the casing to pressing-in.