采用有限元法,研究水库峡谷地形在地震动输入下的地表反应特征。模拟分析结果显示:1)地形特征中的高度、坡度和高宽比的变化对计算模型地表的地震动峰值和频谱的影响特征明显;2)水库峡谷地形迎水面水位上升一般会抑制其山体部分的地震动,减小加速度峰值,其对输入地震动中高频部分的抑制作用更为明显;3)水库峡谷地形场地地表运动对输入地震波的频率很敏感。
The effects of reservoir-canyon topography on the ground motion are analyzed with finite element method and following are obtained. 1 ) The change of the height, the angle and the ratio of height to width of topo- graphic features affect the peak ground acceleration and the spectrum of analytical model obviously. 2)The water level rising of water side will reduce the peak value of ground motion of the mountain part, and the high frequency components of input seismic waves will be inhibited more obviously. 3 )The seismic response is sensitive to the fre- quency of input seismic waves.