Large scale triaxial shear tests on rockfill materials were performed to study the characteristics of dynamic moduli

damping ratios and residual deformations of rockfill materials by the large-scale multifunction triaxial apparatus. The dynamic stress-strain relationship and residual deformation of main rockfill

cushion layer and transitional rockfill under cyclic loading are the focuses of this study. The experimental results show that the dynamic stress-strain relationship is sensitive to shear strain level. The dynamic moduli of rockfill material decreases with the shear strain increasing. Confining pressure and consolidation stress ratio are both proportional to the dynamic moduli. From the results of test and model parameters

the dynamic stress-strain relationships and residual deformation can be described reasonably by the modified nonlinear viscoelastic dynamic constitutive models and empirical formula by Shen Zhujiang

respectively