Soil-cement composite pile forming method and the hollow pile digging device used to it

摘要

PROBLEM TO BE SOLVED: To provide a method of forming a soil cement composite pile capable of preventing earth and sand from rotating together with an agitating blade and sufficiently agitating and kneading cement milk and excavated earth and sand.;SOLUTION: The method of forming the soil cement composite pile is as follows. Namely, using a hollow pile inner excavation device, an excavating rod is rotated in a normal direction while agitating blades on a normal rotation side are extended, and the hollow pile is rotated in the reverse direction interlocking reverse rotation side agitating blades. While a vertical hole is excavated by the excavating rod rotated in the normal direction, the hollow pile rotated in the reverse direction is sunk in the vertical hole. In this process, while a cement hardening liquid is injected into the excavated hole, the hardening liquid and the excavated earth and sand are agitated and kneaded in a plurality of areas of opposite directional rotation and agitation between the vertically adjacent normal rotation side agitating blades and the reverse rotation side agitating blades to form the soil cement. The hollow pile is positioned in the soil cement. When the hollow pile is positioned to an intended depth, the agitating blades on the normal rotation side and the reverse rotation side are closed and contracted, and the excavating rod is pulled out of the hollow pile.;COPYRIGHT: (C)2006,JPO&NCIPI