Wetting-drying effect on response of footing resting on partially saturated soils

Abstract

ABSTRACT Partially saturated soils are common in arid or semi-arid zones. It is a common practice to assume soil as fully saturated for estimation of bearing capacity. With this assumption, estimated bearing capacity is expected to be on conservative side. But sometimes it may be misleading. The motive of this study is to examine the effect of wetting induced collapse on the bearing capacity of shallow foundations. This paper presents the application of improved Barcelona basic model to the simulation of shallow foundation using coupled approach. A boundary value problem of strip footing resting over fully and partially saturated soil is analysed. Different loading and wetting sequences are followed to capture the effect of water table fluctuation on bearing capacity in partially saturated soils. From comparison of numerical prediction with analytical values of ultimate bearing capacity, a relationship for apparent cohesion is suggested for moderate range of angle of internal friction.