PURPOSE:To improve the efficiency of execution by discharging a solidifying material from an injection nozzle installed at the side section of a cylindrical casing and forming an approximately cylindrical solidifying pile within a specified depth range on the outer circumference of a drain pile. CONSTITUTION:A winch drum, etc., are driven, and the lower end section of a cylindrical casing 14 is penetrated up to the specified depth of a second weak stratum. The casing 14 is drawn out while turning the outer rod 21 of the casing 14, and a columnar sand drain pile 26 is formed in the second weak stratum. When the lower end section of the casing 14 reaches a first weak stratum, a solidifying material 25 is discharged from the injection nozzles 23 of the outer rod 21, and a cylindrical solidifying pile 27 is created around a sand drain pile 26. The cylindrical solidifying pile 27 is created while preparing the first weak stratum, the second weak stratum, a superior stratum, and the sand drain pile 26 penetrated through a sand mat.
展开▼
