【摘要】 地震动输入是进行土层场地或土-结构相互作用体系地震反应分析的重要一步。通过波场分解,将人工边界上的波动场分解为自由波场和散射波场,其中人工边界上的自由波场根据波在自由表面的反射理论求得,散射波场由黏性人工边界直接吸收,进而在人工边界上施加等效荷载实现斜入射地震波作用的输入。借助MATLAB辅助计算程序和FLAC3D的前后处理功能,进行不同角度(0°和30°)入射条件下SV波作用的时域数值模拟计算,数值解和理论解吻合较好。算例表明,采用黏性人工边界和等效荷载输入方法具有较高的计算精度,建立的数值模拟方法为土层场地和土-结构动力相互作用在地震波斜入射下的反应分析提供了简单易行的计算途径。更多还原

【Abstract】 Earthquake input is very important for seismic response analysis of soil site or soil-structure interaction system.Through the wave field decomposition,the wave field on artificial boundary is separated into the free wave field and the scattering wave field.The free wave field on artificial boundary can be obtained according to the free-surface reflection theory of plane wave,and the scattering wave field is abstracted by viscous artificial boundary.Then the obliquely incident seismic wave is realized by input of equivalent loadings applied to the artificial boundary.Based on the aided calculating program by MATLAB and pre-progressing and past-progressing technology of FLAC3D,the time domain numerical simulation for a simple finite element model is done under SV wave by different incident angles(0° and 30°).The numerical results are very closed to the theory solution,which shows the method of using viscous artificial boundary and equivalent loads input has good computational accuracy,and the numerical simulation method can provide an effective way for response analysis for soil site or soil-structure dynamic interaction under obliquely incident seismic waves.更多还原