Abstract: To compare CLoE and Gudehus-Bauer hypoplastic models, a series of finite element analyses were carried out on modeling the strain localization for Hostun sand under plane strain condition. The strain localization was analyzed mainly in terms of different confining pressures and same initial imperfection. The results are drawn as follows. (1) Compressive hardening can be observed by two hypoplastic models; the stiffness of Hostun sand rises with the increasing of confining pressures. (2) The pattern of strain localization from the results of CLoE hypoplastic model is more compatible with the results of experiments than Gudehus-Bauer model. (3) CLoE hypoplastic model can simulate volume expansion before shrink with the increase of load of Hostun sand. (4) The softening behavior under high confining pressures of the elements in strain localization is more obvious in the strain-stress curve based on CLoE hypoplastic model. (5) CLoE hypoplastic model is better than Gudehus-Bauer model in simulating the nonuniform strain localization which is caused by initial imperfection. All in all, numerical results suggest that CLoE model performs better than Gudehus-Bauer model in modeling strain localization. What’s more, influences of confining pressure and initial imperfection can be modeled by CLoE hypoplastic model. However, CLoE model should be improved because of void ratio and intrinsic length scales unconsidered.

Key words: granular materials, hypoplasticity, strain localization, finite element simulation