摘要
采用有限元方法计算了SV波入射下均匀半空间和层状半空间圆弧形凸起地形的地震响应。比较分析了不同入射波频率,入射角度和凸起高宽比情形对圆弧形凸起地形地表谱放大系数β的影响及凸起圆弧形的两脚点和顶点的时程比较分析,得到结论:(1)不同的无量纲频率η、入射角度θ和不同的高宽比h/a对圆弧形凸起的位移谱放大系数影响显著,随着无量纲频率η、入射角度θ和高宽比h/a增大,位移谱放大系数β的影响越大;(2)圆弧形凸起地形对于地震动的影响非常显著,在山顶处对地震动具有显著的放大作用,而在山脚处对地震动具有一定程度的削弱作用;(3)SV波入射下层状半空间与均匀半空间圆弧形凸起地形的地震响应存在明显差异,在|(x/a)|≤1.0范围内,层状半空间的地表位移谱放大系数明显大于均匀半空间的放大系数;在|(x/a)|>1.0范围内,有层状半空间的地表位移谱放大系数小于均匀半空间的放大系数的情形出现。
In this paper,the finite element method is used to calculate the seismic response of uniform half-space and layered half-space arc-shaped convex terrain under SV wave incident.The paper compared and analyzed the influence of the spectral amplification factorβon the topography of the circular arc bulge under different incident wave frequencies,incident angles and the aspect ratio of the bulge,and the time history of the two points and the vertex of the circular arc bulge,then the following conclusions were obtained:(1)Different incident frequencyη,incident angleθand different aspect ratio h/a have significant effects on the displacement spectrum amplification coefficient of arc-shaped convex,and with the increase of incident frequencyη,incident angleθand aspect ratio h/a,the displacement spectrum amplification coefficientβbecomes complicated.(2)The circular convex terrain has a very significant impact on ground motion,which has a significant amplification effect on the ground motion at the top of the mountain and a certain degree of weakening effect on the ground motion at the foot of the mountain.(3)The incident SV wave shape of the lower half space and bumps on the seismic response of terrain of uniform half space circular arc form shows obvious difference,and within the range≤1.0,the layered half space spectrum of surface displacement amplification factor significantly is greater than the amplification coefficient of uniform half space;in the range>1.0,a layered half space spectrum of surface displacement amplification coefficient is less than the amplification coefficient of uniform half space situation.
作者
孙青
丁海平
张如艳
SUN Qing;DING Haiping;ZHUANG Ruyan(Key Laboratory of Structural Engineering of Jiangsu Province,USTS,Suzhou 215011,China)
出处
《苏州科技大学学报（工程技术版）》
CAS
2023年第3期1-7,共7页
Journal of Suzhou University of Science and Technology（Engineering and Technology Edition）
基金
国家自然科学青年基金项目(51808371)。
关键词
圆弧形凸起地形
SV波
无量纲频率
高宽比
地震响应
circular arc raised terrain
SV wave
dimensionless frequency
aspect ratio
seismic response
