Permeability and Deformation Characteristics of Tianjin Clays under Coupled Dynamic Stress and Seepage Fields

Abstract

The permeability and deformation characteristics of Tianjin clays under coupled dynamic stress and seepage fields is a major concern in the geotechnical engineering field. In this study, a group of samples were tested in the laboratory using cyclic triaxial tests considering different parameters, including the number of cycles, cyclic stress ratio (CSR) and back pressures. The frequency of cyclic loading was kept constant at 1 Hz. The laboratory results show that the hydraulic conductivity is correlated with the void ratio by a unique curve under the same value of the CSR. The void ratio decreases with an increase in the number of cycles, which in turn decreases the hydraulic conductivity. In addition, an empirical equation for the degradation index is investigated. The hysteretic curves of the soil are also analysed to evaluate the size of the energy accumulative consumption and dynamic deformation characteristics. The results of this study illustrate that the deformation of Tianjin clays subjected to cyclic loading and seepage permeability should be determined in engineering practice.