Research on the Dynamic Characteristics of Silty Clay under Wave Load and Rotation of Principal Stress Axes

In this study, the GDS dynamic hollow cylinder apparatus was used to conduct dynamic cyclic torsional tests and post-cyclic shear tests on silty clay in Taizhou, Zhejiang Province, considering different degrees of principal stress rotation under wave loads. The cyclic behaviours of silty clay under wave loads were obtained and analyzed, such as the development of pore water pressure, the stress-strain relationship, the backbone curve and the stiffness softening. Also, we established the model of backbone curve considering the number of cycles and degrees of principal stress rotation. Furthermore, in the post-cyclic tests, the degree of principal stress rotation positively affects the shear strength and negatively affects the accumulation of pore water pressure during the shearing. This study provides new experimental basis and theoretical reference for the engineering property evaluation of saturated silty clay under wave loads.