In this chapter, the probabilistic porous-solid model is used to simulate the tensile strength of unsaturated soils tested at different water contents. The strength of unsaturated soils can be split in two parts: one related to the net stress and the other to suction. The strength generated by suction has its origin on the additional contact stresses induced to solid particles by water meniscus. This additional contact stress is called matric suction stress. In that sense, the tensile strength of soils represents the matric suction stress of the material at that particular water content. The numerical and experimental comparisons of the tensile strength of unsaturated soils tested at different water contents show that the probabilistic porous-solid model can simulate this phenomenon with sufficient accuracy.
Keywords: Additional contact stress, Cohesion, Direct tensile test, Effective stress, Homogenous material, Matric suction stress, Net stress, Probabilistic porous-solid model, Retention curves, Suction, Tensile strength, Tensile stress, Water menisci.