Dynamic Shear Modulus Damping Ratio Test And Dynamic Constitutive Relation Of Pearl River Delta Soft Soil

The dynamic characteristics of soft soil and the seismic response analysis of the site are the hot areas that the seismic engineering community has been paying attention to and research.The dynamic shear modulus damping ratio is also an important parameter for seismic design,because almost all the sites covering the soft soil are not.Actual strong vibration observation data,which makes potential problems in the safety and reliability of seismic design in these areas.Aiming at the dynamic characteristics of soft soil and the uncertainty of site seismic response analysis,this paper adopts the theory,experiment and numerical simulation method,and the dynamic characteristics,dynamic constitutive model selection and site ground motion response under different factors under cyclic loading.Analysis and other issues.The goal is to find out the law of the influence of different factors on the dynamic characteristics,the applicability of the viscoelastic model to soft soil and the reasonable estimation of ground motion effects,and provide a basis for seismic fortification of engineering in this area of China.Based on the previous studies,this paper has done the following work for the Pearl River soft soil:1.Based on the determination of the relevant physical properties of the soil,a dynamic triaxial test was carried out to analyze the variation of the confining pressure,consolidation stress ratio,dynamic load frequency and dry density on the dynamic characteristics of the Pearl River Delta soft soil.2.The viscoelastic model is selected to fit the dynamic triaxial test data,and the maximum dynamic shear modulus Gmax,shear modulus ratio-dynamic strain curve,damping ratiodynamic strain curve are obtained,and the applicability of the model is given.Eight sets of classical shear modulus ratios and damping ratios.3.The seismic response analysis program of the time domain nonlinear field is compiled,the analysis model is established,the seismic response analysis is carried out,and the difference between the method and the equivalent linear analysis method is discussed.