Change of pore-water pressure on creep behavior of an unsaturated silty soil

Abstract

Slope failure induced by rainfall is related to change of effective stress, and both saturated soils and unsaturated soils had been evaluated in effective stress theory. The effective stress comprised confining pressure and pore-water pressure, and unsaturated soil necessary to two stress variables such as net normal stress and matric suction. Before occurrence of slope failure, soils stated under stress condition, which was not isotopic compression stress. Therefore, it was estimated that lateral stress was lower than overburden pressure or dead loading pressure in practice. Mechanical deformations as consolidation or creep behavior was revealed, and associated to slope failure, differential settlement and lateral flow. At least, these problems have been recognized of geotechnical disasters.