A STRAIN HARDENING MODEL REFLECTING STRESS PATH CORRELATION OF CORASE-GRAINED MATERIALS

Coarse-grained materials have become main filling materials of high fill engineering in mountainous areas, and building a constitutive model, which can well reflect its stress-strain behavior, is significant for the simulation analysis and safety evaluation of high fill engineering. On the basis of analyzing large scale triaxial experimental results, a new elastic-plastic model is proposed by combining the hardening soil model and the modified cam-clay model, in which the logarithmic relation of strength parameters of coarse-grained materials is also adopted. The new model can not only reflect the nonlinear deformation behavior, nonlinear strength property, confining stress dependence of stiffness, and dilatancy of coarse-grained materials, but also is capable of considering the stress path correlation and simulating the deformation of coarse-grained materials under complex stress paths. Besides, the model parameters can be defined by conventional triaxial experiments. Finally, the model is validated by comparing with different stress path experimental results on coarse-grained materials.