Air injection structure to the sandy ground and prevent liquefaction method of sandy ground

摘要

PROBLEM TO BE SOLVED: To provide a liquefaction prevention method for sandy ground and a structure for air injection which prevent the air injected through a pipe buried in an installation hole of the sandy ground, which is saturated with water, from leaking through the gap formed around the outer peripheral surface of the pipe and around the inner peripheral surface of the installation hole so that the degree of saturation may be lowered by the injected air.;SOLUTION: The pipe 3 is internally inserted into a casing pipe inscribed to the installation hole 1 formed in the sandy ground saturated with the water, and silica sand S is filled between the casing pipe and the pipe 3 to the position where an air injection hole 4 of the pipe 3 is buried, so that a filter layer 5 may be formed. Next, an airtight filling material is filled to form an airtight layer 6. Then, after backfilling of the part above the airtight layer 6 and pulling out the casing pipe, the air A from an air supplying device 9 is injected into the ground from the air injection hole 4. When the gap is formed around the outer peripheral surface of the pipe 3 and around the inner peripheral surface of the installation hole, the airtight layer 6 prevents the air A from leaking to the ground surface.;COPYRIGHT: (C)2009,JPO&INPIT