Amplification Of SH And Love Waves By A Canyon In A Layered Half-space

Many investigations of earthquake damage shows that local site conditions have significant effects on ground motion, and therefore, there is intimate relationship between intensity abnormity and site condition. Canyon is one of the most important local sites, its site response analysis has been an attractive research topic in recent years, and research in this problem has an important theoretical meaning. Natural soil was simplified as sotropy elastic solid medium before, however, for the different depositional age of the natural soil, we need using layered media to reflect the heterogeneity along with depth.This text is just under this kind of background, which studies the amplification of SH and Love waves by a canyon in layered half-spaces.The amplification of SH waves and Love waves by a canyon in layered site is analyzed by using the indirect boundary-element method in this paper. Three different thickness layered site with different stiffness ration of the rock and soil is analyzed.From amplification curve, we know that the amplification of SH waves and Love waves depend on the thickness of soil,stiffness ration of the rock and soil and dimensionless frequency greatly. From the amplification spectrum, we can see, for the SH waves all the dot in the canyon surface have much frequency which make the resonance phenomenon, and the thickness of soil influence the resonant frequency greatly which increase along with the stiffness ration of the rock and soil. For the love waves, the initial frequency of high order model is determined by the thickness of soil. Along with the increasing of the stiffness ration of the rock and soil, the amplification of each model converges more quickly. The convergence is different from the dot in the canyon surface.