Discussion on the influencing factors of seismic response calculation of soil layer

Abstract

In this paper, H-D model and Davidenkov model were used to fit soil layer parameters, and the influence of constitutive model on seismic response calculation of soil layer was discussed. It Select one soil layer profile in each of the sites of class Ⅱ, Ⅲ and Ⅳ, and select the interface of shear wave velocity 500 m/s as the ground motion input interface. The underlying soil layer is considered to be consistent with the input soil layer, and 6 input interfaces of 5～30 m are taken downward. Imperial Valley wave, Northridge wave and Kobe wave were selected as input ground motion were calculated by one-dimensional equivalent linearization method. The influence of input interface selection on soil layer seismic response calculation was discussed. Through the analysis of the results obtained: ① The goodness of fit of Davidenkov model is better than H-D model for soft soil, but there is little difference in ground motion response obtained by the two models. PGA only shows a certain difference under the input of 0.40 g amplitude. ② The peak acceleration of the surface increases with the increase of depth within a certain thickness of the underlying soil layer. Within a certain thickness of ground surface acceleration response spectrum, it decreases with increasing depth in short period, and increases with increasing wave peak in long period. ③ Site seismic response analysis when the shear wave velocity of 500 m/s is selected as the final layer and input interface of the drilling hole, it is appropriate to consider the underlying soil layer of 5～20 m thickness with the same property as the final layer as the input interface.

Keywords

• seismic bedrock interface
• constitutive relations of soils
• pga
• ground acceleration response spectrum