IMPROVING METHOD FOR SOFT GROUND

PROBLEM TO BE SOLVED: To provide an improving method for a soft ground capable of freely controlling a loading pressure on the ground, capable of efficiently discharging water and air contained in the soft ground surely and being effectively used even as a measure against residual-settlement in place of a bank for increasing the bearing capacity of the ground after soil improving. SOLUTION: In the improving method for the soft ground, the top face of improving soil A is covered with airtight sheets 21 fixing sheet terminals into the peripheral sections B of the improved soil, and a decompression region separated from the improved-soil peripheral section B is made in the improving soil A by loading a vacuum pressure under the airtight sheets 21, and pore water in the improving soil A is discharged to improve the improving soil A to a hard ground. In the improving method for the soft ground, the airtight sheets 21 have a double structure composed of upper sheets 22 and lower sheets 23. In the improving method for the soft ground, a fluid is injected into openings 24 among the upper sheets 22 and lower sheets 23 under the state, in which the bulging of the upper sheets 22 of the airtight sheets 21 are suppressed, and only the lower sheets 23 are made to bulge and the improving soil A is pressed. COPYRIGHT: (C)2008,JPO&INPIT