A study on the reflection of plane-S-waves at a free boundary of unsaturated soil
CHEN Wei-yun1，2, XIA Tang-dai1，2, LIU Zhi-jun1，2, Zhou Xin-min3
1. MOE Key Laboratory of Soft Soils and Geoenviromental Engineering, Zhejiang University, Hangzhou 310058, China；2. Institute of Geotechnical Enginering, Zhejiang University, Hangzhou 310058, China3. Seismological Bureau of Zhejiang Province, Hangzhou 310013, China
Abstract：The unsaturated poroelasticity theory is used to describe the propagation characteristics of elastic waves in unsaturated soil, and the reflection problem of plane-S-waves at the free boundary of unsaturated soil is analyzed. According to the boundary conditions, the theoretical expressions of the amplitude reflection ratios and energy reflection ratios for the four reflected waves at the boundary, i.e., reflected P1 wave, reflected P2 wave, reflected P3wave and reflected S wave, are respectively derived and the numerical calculations are then carried out. The effects of the incident angle of plane-S-waves and saturation degree of the soil layer on the amplitude reflection ratios and energy reflection ratios of the four reflected waves are discussed in the numerical example. It is shown that the amplitude reflection ratios and energy reflection ratios of the various waves are influenced by not only the incident angle but also the saturation degree. These conclusions are useful for the theoretical researches of soil dynamics and related seismic exploration projects.
陈炜昀;夏唐代;刘志军;周新民. 平面S波在非饱和土自由边界上的反射问题研究[J]. , 2013, 32(1): 99-103.
CHEN Wei-yun;XIA Tang-dai;LIU Zhi-jun;Zhou Xin-min. A study on the reflection of plane-S-waves at a free boundary of unsaturated soil. , 2013, 32(1): 99-103.
2013, Vol. 32 
