【摘要】 以均匀弹性半空间解析Rayleigh面波作为波动有限元模型的入射场,计算分析了软、硬盆地介质参数、盆地尺寸等对Rayleigh面波地震动的影响规律,给出了盆地场地模型的Rayleigh面波地震图及其传播过程。主要认识有:1)沉积盆地介质由软变硬,对Rayleigh面波地表地震动的放大作用由大变小。2)盆地尺寸对Rayleigh面波地震动的影响,主要体现在对水平或竖向地震动走时的提前或滞后上。这与体波情形相类似。3)Rayleigh面波地震动作用下,软、硬方形盆地的"边缘效应"体现为地震动反应与周围介质有可观的差异;"盆地效应"体现为盆地介质不仅对地震动幅值有显著影响,而且会发现盆地边缘产生的在盆地区域内传播的多次反射波的存在,导致地震动持时的延长。更多还原

【Abstract】 Analytical Rayleigh wave surface wave in homogeneous elastic half-space as the incident field of wave propagation-finite element model,the effect law of the Rayleigh surface wave ground motion on the soft and hard medium parameters,the dimensions of the basin are calculated and analyzed,at the same time,Rayleigh surface wave field seismograms and its propagation process of the basin model are given.The main conclusions are: 1) the amplification effect of the Rayleigh surface wave ground motion is from large to small,when sedimentary basins media from soft to hard.2) The situation that the basin dimensional size on the Rayleigh surface wave ground motion are mainly showed that the travel time of the horizontal or vertical ground motion is ahead or lag,which is similar with the body wave.3) Under the action of Rayleigh surface wave ground motions,the "edge effect" of the soft and hard square basin reflects that the ground motion response have a considerable difference to the surrounding medium.The "basin effect" shows not only the ground motion amplitude is significantly affected by the basin medium,but also the duration of ground motion is extended because the existence of multiple reflected waves,which is generated from the basin edge,and is free propagating in the basin area.更多还原