| 摘要 |
PROBLEM TO BE SOLVED: To provide a liquefaction prevention method which prevents ground subsidence and reduces the occurrence of noise and vibration considerably and can be applied to a subgrade having a large fine-grained fraction content while considering p-H environment.SOLUTION: In an inventive liquefaction prevention method: at first, a casing pipe 2 is pressed vertically downward into a subgrade 1 which is a liquefaction prevention object to form a drill hole 3 in a shape in which a hole wall 5 is protected by the casing pipe 2 (a step 101); next, a filler 4 is charged in an internal space of the casing pipe 2 (a step 102); and next, the casing pipe 2 is extracted upward by the amount corresponding to the charged amount of the filler while pushing the filler 4 by the pressure of the air supplied into the casing pipe 2 (a step 103). Then, the steps 102 to 103 are repeatedly performed until the filler 4 is arranged in a pile shape, for example, over a depth range from a bottom surface of the drill hole 3 to the ground water level (a step 104). |
