Non-uniform ground motion characteristics and influencing factors of valley site under oblique incidence of SH wave
ZHAO Leichao1, SONG Zhiqiang1, WANG Fei1, LIU Yunhe1, ZHANG Cunhui2
1.State Key Lab of Ecological Water Conservancy in Northwest Arid Area, Xi’an University of Technology, Xi’an 710048, China;
2.Changjiang Institute of Survey, Planning, Design and Research, Co., Ltd., Wuhan 420100, China
Abstract：Based on the indirect boundary integral equation method (IBIEM), the characteristics and distribution of ground motion on the surface of trapezoidal canyon under SH wave incidence were analyzed, and the influence mechanism of seismic wave oblique incidence Angle, slope slope, base width and site shear wave velocity on ground motion characteristics and non-uniform distribution was studied.The effect of canyon scattering on ground motion field at the truncated boundary of foundation under different shear wave velocities is deeply analyzed. The results show that with the increase of the angle of incidence, the amplification effect of the left slope increases gradually, and the more obvious the non-uniform distribution of ground motion on both sides of the bank. As the slope slows down, the amplification area caused by terrain scattering effect gradually expands to the right, and the seismic non-uniformity at the top and toe of the slope on both banks increases; With the increase of bottom width, the amplification area caused by terrain scattering effect gradually expands from right to side, the relative displacement of slope toe is sensitive to the change of bottom width, and the non-uniform characteristics of ground motion at both sides of slope toe are enhanced; When the wave velocity is small, the scattering effect of canyon is significant, and the maximum displacement of the left slope top is 1.45 times that of the right slope top, and the non-uniform characteristics of ground motion between the two banks is obvious. When truncating boundary input ground motion, the scattering effect of canyon topography should be fully considered, and the total field composed of free field and scattered field should be taken as the input to obtain reasonable and accurate ground motion input. •••••••
Key words: IBIEM; canyon topography; SH wave; non-uniform characteristic; Scattering effect
赵磊超1，宋志强1,王飞1，刘云贺1，张存慧2. SH波斜入射下河谷场地非一致地震动特性及影响因素分析[J]. 振动与冲击, 2022, 41(23): 109-118.
ZHAO Leichao1, SONG Zhiqiang1, WANG Fei1, LIU Yunhe1, ZHANG Cunhui2. Non-uniform ground motion characteristics and influencing factors of valley site under oblique incidence of SH wave. JOURNAL OF VIBRATION AND SHOCK, 2022, 41(23): 109-118.
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