基岩场地软弱夹层对地表峰值加速度的影响

某些基岩场地内部含有软弱夹层,其对地表地震反应的影响如何,目前尚无深入研究。利用一维土层地震反应的等效线性化波动方法,选取了典型地震波作为输入,研究了不同强度地震动输入下基岩场地软弱夹层埋深、厚度和剪切波速对地表峰值加速度的影响。初步研究结果表明:输入地震动强度不改变软弱夹层埋深、厚度和剪切波速对地表峰值加速度的影响规律,地表峰值加速度变化规律受软弱夹层埋深、剪切波速及厚度共同作用的影响。

EFFECTS OF SOFT INTERLAYER WITHIN BASE-ROCK SITE ON PEAK ACCELERATION OF SURFACE GROUND MOTION

The effects of soft interlayer within some rock sites on seismic response of ground surface are rarely studied. The effects of the depth, thickness and shear velocity of soft interlayer within rock sites on surface peak acceleration are analyzed using one-dimensional equivalent linear method of soil seismic response on the basis of the wave motion model. Primary results show that the intensity of input ground motion doesn’t change the laws of the effects of the depth, thickness and shear velocity of soft interlayer within rock sites on surface peak acceleration, and that the varying laws of surface peak acceration affected by the depth, thickness and shear velocity of soft interlayer are controlled by the comprehensive influences of the three factors.