An experimental study on small suction of sand particles and its contribution to the stability of cavity

Abstract

Recently, several occurrences of cave-in on sandy ground have been reported. Previous research shows that the interparticle cohesion such as suction is essential for the stability of a subsurface cavity in sandy ground. In this research, suction measurement tests on granular materials were conducted using a simple suction measuring device. A series of simple model tests were also carried out to consider the contribution of suction to the stability of cavity. It was revealed that matric suction of sandy soil is affected by the grain size and shape under a given degree of saturation. Further, not only suction but also surface roughness, shape and formation of arch contribute to the stability of cavity.