摘要
采用有限元数值模拟方法探讨了在SV波斜入射时,入射角度θ、入射方向和陡坎坡角α等参数变化对陡坎场地地表震动加速度峰值放大系数影响。结果表明:1)对x分量,从陡坎底部到陡坎顶部,放大系数逐渐增大,入射角度、坡角和入射方向没有影响;对z分量,放大系数分布规律相对复杂。2)入射角度θ一定时,无论地震波顺着陡坎方向(左)入射还是逆着陡坎方向(右)入射,陡坎上侧的放大系数大于陡坎下侧的放大系数。同时,放大系数随着坡角α的增大而增大。3)坡角α不变,地震波顺着陡坎方向(左)入射时,x分量的放大系数随着入射角的增大而减小,z分量的放大系数随着入射角的增大而增大。4)地震波逆着陡坎方向(右)入射时,x分量放大系数随入射角的变化与输入波有关,但最大值基本在陡坎上侧边缘。z分量放大系数随入射角的增大而增大,最大值的位置无一致规律。5)地震波顺着陡坎方向(左)入射时,x分量的放大系数比地震波逆着陡坎方向(右)入射时的小,z分量与之相反。
The seismic ground motion of a scarp topography under inclined SV waves is analyzed by using finite element numerical simulation method,and the effects caused by incident degrees θ,the incident directions and the slope angle α are also discussed. Results show that： 1） The amplification factor of the x component is increased gradually from scarp bottom to top,and the incident degrees,the slope angle and the incident directions have no effect. While it is relatively complex for z component. 2） When the incident degree is a constant,the amplification factor of scarp upside region is greater than that of scarp downside region,regardless of the incident direction,which increases with the increase of slope angel. 3） When the slope angle is a constant and incident direction is along the scarp,for x component,amplification factor decreases with the increase of incident angle,while for z component,amplification factors are increased. 4） If incident direction is against the scarp,the amplification factor of x component change with the input wave,while the maximum factor is at top edge of scarp. The amplification factor of z component increases with the increase of incident angle,but location of the maximum value has no uniform trend. 5） For x component,amplification factor is smaller for incident direction along the scarp than for against the scarp. And for z component,the effect of incident direction of wave is reverse.
出处
《自然灾害学报》
CSCD
北大核心
2017年第4期39-47,共9页
Journal of Natural Disasters
基金
国家自然科学基金(51278323)~~
关键词
陡坎地形
SV波斜入射
地面运动
放大系数
scarp topography
inclined SV wave
ground motion
amplification factor
