Distribution characteristics of dynamic parameter curves of different soils and their effects on ground motion

The dynamic shear modulus ratio and damping ratio are the important dynamic parameters that characterize the nonlinear characteristics of soils, and are also one of the important factors affecting the seismic response characteristics of the site. The statistical analysis on common soil types in multiple literatures is conducted, and obtains the corresponding distribution characteristics of dynamic parameter curves of soils are obtained. Based on this, the influence characteristics and laws of the distribution characteristics of dynamic shear modulus ratio and damping ratio curves of soils on site effects are studied. The research results indicate that there is a certain degree of difference between the average and recommended values of the two dynamic curves of various types of soils, but the overall trend is consistent. Among them, the distribution of the two dynamic curves of soil types such as sand, clay, gravel soil and muddy soil has their own characteristics. Due to the combined influences of the dynamic shear modulus ratio and damping ratio, the site effects of each component of seismic motion exhibit different characteristics, generally manifested as low-frequency amplification effects and high-frequency filtering effects. The soil types with different distribution characteristics of dynamic shear modulus ratio and damping ratio have different degrees of influences on the two effects.