METHOD OF CONSTRUCTING SOIL IMPROVING COMPOSITE PILE STRUCTURE, AND APPARATUS FOR CONSTRUCTING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a method of constructing a composite body of piles of a pile foundation or settling preventive piles for use in a soil improving direct foundation, and soil improving bodies, by completely combining the former with the latter, and to provide an apparatus for constructing the same.;SOLUTION: The method is composed of the following stages. In the first stage, the piles are driven into the ground to a necessary depth before or in parallel with the construction of the soil improving bodies. In the second stage, a deep stratum mixing machine which has at least two shafts is employed. One of the agitating/mixing shafts is replaced by an agitating/mixing cylindrical shaft which has a hollow cylindrical shape having an inner diameter larger than the external diameter of the pile, and allows in-situ excavated soil and injected cement milk to flow therein to carry out agitating/mixing work. Alternatively a modified deep stratum mixing machine originally provided with the agitating/mixing cylindrical shaft is employed. Then the agitating/mixing cylindrical shaft is penetrated into the ground along the pile and concentrically with the pile to a scheduled depth of soil improvement, then the injected cement milk and the in-situ soil are agitated and mixed to improve the ground around the pile, and at the same time the improved ground is partially overlaid with the soil improved pile constructed by the other agitating/mixing shaft.;COPYRIGHT: (C)2008,JPO&INPIT