The ground improvement method by curing material injection using high pressure water jets

摘要

PURPOSE:To form a hardened foundation in the ground by filling a foundation hardener into a guide hole which is drilled into the ground by a predetermined depth while jetting high pressure jet water and air from upper nozzles. CONSTITUTION:A guide hole 6 is formed with the use of a boring machine 10. Then, hoses are coupled to a triple pipe swivel 5 on a rod A. Air and high pressure jet water are simultaneously jetted from a high pressure jet nozzle 4 and an air nozzle 4, respectively, and muddy water 17 is jetted from a hardening agent filling nozzle 2 while the rod A is elevated in order to carry out pretreatment. Further, the rod A is lowered down to the bottom position, and a hardening agent 7 is discharged while the high pressure water and air are jetted. Then the muddy water and slime are elevated in the guide hole 6 together with water under air-lift action, and accordingly, they are discharged. Thus, a foundation consisting of an exoskeleton layer or a deep layer can be formed into an improved foundation layer having a predetermined effective diameter.