In this chapter, the probabilistic porous-solid model is used to simulate the
tensional 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 tensional strength of soils represents the
matric suction stress of the material at that particular water content. The numerical and
experimental comparisons of the tensional strength of unsaturated soils tested at
different water contents show that the probabilistic porous-solid model can simulate this
phenomenon with sufficient accuracy.
Keywords: Direct tension test, water meniscus, tension stress, suction, matric
suction stress, additional contact stress, tensional strength, probabilistic poroussolid
model, effective stress, net stress, suction, cohesion, water menisci,
homogenous material, retention curves.