Behaviour of Partially Saturated Soil Under Isotropic and Triaxial Condition Using Modified BBM

Abstract

How suction influence the shear strength of partially saturated soil is one of the important challenges in many geotechnical problems. As compared to saturated soil, the triaxial compression stress path for partially saturated soil is more complex. In the present study a single element finite element model has been developed and implemented in FORTRAN code. An explicit integration algorithm is adapted to Barcelona basic model with some modification considering locus of apparent tensile strength in the p?–s plane as non-linear, anisotropy to the yield surface and dependence of degree of saturation on volumetric strain. The performance of the code is examined and verified with suction controlled triaxial experimental results. Application of isotropic compression, wetting and triaxial compression stress path on model demonstrated significant influence of stress paths on strength and deformation behaviour of partially saturated soil. © 2017, Indian Geotechnical Society.