Comparison of Simulating Loess Deformation by Two Advanced and Conventional Constitutive Models

Choosing an appropriate constitutive model for soil is the key to ensure the quantitative accuracy of modeling geotechnical problems. In recent years, two kinds of models, i.e., the hardening soil model (HS model) and the hardening soil model with a small strain stiffness (HSS model) have shown the good validity and advanced nature in existing studies. There are, however, rare reports on their applications in engineering problems of loess. For this goal, in allusion to the laboratory triaxial compression test of loess and the field plate load test on the loess ground, the HS and HSS models as well as the commonly used Mohr-Coulomb model (M-C model) and Duncan-Chang model (D-C model) in the finite element software Diana were employed to carry out a comparison study of numerical modeling. The results show that the HS and HSS models are better than the M-C and D-C models in fitting the resuts of the two tests, and overall, the fitting results by the HSS model are better than those by the HS model. Therefore, the HS and HSS models are more reliable than the latter two in the aspects of modeling the deformation of loess as well as its mechanism of instability and failure, and are of the value to be popularized.