The Seismic Response Analysis Of The Site Containing Soft Soil Interlayer And The Structure On It

The site conditions on the earthquake motion research field has been a very hot topic. Influence factor for soil and the earthquake response to a structure is very complex in site condition. In the site with soft soil layer is a kind of typical geological conditions of common engineering field, but the division method of site classification at Code for Seismic Design of Buildings is not suitable for this type of site. And the current domestic standards for the site with soft soil layer has not made a clear and universal practical design rules. This article as a starting point, to establish the model of soil with soft soil, combined with a short-cycle structure on the surface, input seismic waves on bedrock by using the time history analysis and put to use the finite element analysis by ABAQUS considering the nonlinear behavior of soil. After calculation we found that covering soil on the bedrock surface to amplification of earthquake acceleration is less than no soft soil site In the field of soft soil layer. Strain of soft soil layer under seismic action is larger than the other soil, and dissipation of seismic energy also is greater. The basement structure has a certain degree of weakening of acceleration. Peak acceleration at the top of the structure is usually greater than the bottom of the structure. It is even more significant on the ground motion response by changing the thickness of soft soil layer when we change the Elastic modulus ratio of soft soil and hard soil. The difference of soil elastic modulus to Soft soil and hard soil is bigger, so the acceleration magnified effect is smaller. But there is no linear relationship between them. When the elastic modulus ratio of soft soil and hard soil is greater than a certain value, there is a smaller effect to the peak acceleration. Combined with the analysis of the process and results of the article, this thesis puts forward the research direction for improvement. For example, Comparative analysis using the response spectrum method or calculated by a large data of the actual earthquake records or established a three-dimensional solid model with a reasonable constitutive relation of soil or Combined with the engineering samples to comparative analysis and statistical investigation and so on.