Time-domain dynamic constitutive model suitable for mucky soil site seismic response

Abstract

Soil nonlinear behavior displays noticeable effects on the site seismic response. This study proposes a new functional expression of the skeleton curve to replace the hyperbolic skeleton curve. By integrating shear modulus and combining the dynamic skeleton curve and the damping degradation coefficient, the constitutive equation of the logarithmic dynamic skeleton can be obtained, which considers the damping effect in a soil dynamics problem. Based on the finite difference method and the multi-transmitting boundary condition, a 1D site seismic response analysis program called Soilresp1D has been developed herein and used to analyze the time-domain seismic response in three types of sites. At the same time, this study also provides numerical simulation results based on the hyperbolic constitutive model and the equivalent linear method. The results verify the rationality of the new soil dynamic constitutive model. It can analyze the mucky soil site nonlinear seismic response, reflecting the deformation characteristics and damping effect of the silty soil. The hysteresis loop area is more extensive, and the residual strain is evident.