摘要
运用非饱和孔隙介质理论阐述了弹性波在非饱和土中的传播特性,分析了平面S波在非饱和土层自由边界上的反射问题。根据边界条件,分别导出了在非饱和土自由边界上的四种反射波:反射P1波、反射P2波、反射P3波及反射S波的振幅反射率及能量反射率的理论表达式,并在此基础上进行了数值计算。算例中讨论了四种反射波的振幅反射率及能量反射率受平面S波入射角度及土层饱和度变化的影响情况。计算结果表明:各反射波的振幅反射率及能量反射率不仅与入射角有关,也受到饱和度变化的影响,结论对土动力学的理论研究以及相关工程地震勘探具有一定指导意义。
The unsaturated poroelasticity theory was 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 was analyzed. According to the boundary conditions, the theoretical expressions of amplitude reflection ratios and energy reflection ratios for the four reflected waves including reflected P1 wave, reflected P2 one, reflected P3 one and reflected S one at the boundary were respectively derived and the numerical calculations were then performed. The effects of incident angle of plane-S-waves and saturation level of soil layer on the amplitude reflection ratios and energy reflection ratios of the four reflected waves were discussed in numerical examples. It was shown that amplitude reflection ratios and energy reflection ratios of various reflected waves are influenced by not only incident angle but also saturation level. The results were useful for the theoretical study on soil dynamics and the related seismic exploration projects.
出处
《振动与冲击》
EI
CSCD
北大核心
2013年第1期99-103,127,共6页
Journal of Vibration and Shock
基金
浙江省重点科技创新团队支持计划资助(2009R50050)
关键词
土动力学
平面S波
非饱和土
弹性波反射
soil dynamics
plane-S-wave
unsaturated soil
elastic wave reflection
