高陡边坡地震动放大效应分析  

Ground Motion Amplification Effect of High and Steep Slopes

作　　者：刘立波 李海波[1] 刘亚群[1] 

机构地区：[1]中国科学院武汉岩土力学研究所,武汉430071

出　　处：《长江科学院院报》2017年第9期98-103,共6页Journal of Changjiang River Scientific Research Institute

基　　金：国家杰出青年科学基金项目(51025935)

摘　　要：为了研究高陡岩质边坡对地震动加速度峰值的放大作用,分别针对简谐波和El Centro波竖向入射高陡边坡的情形,基于动力学模拟研究了坡肩和坡表面放大系数与坡高和坡比的参数关系。根据计算结果绘制边坡剖面的水平向和竖向放大系数等值线图,分析了坡体内放大系数分布特征。结果表明:放大系数并不随着坡高的递增而持续增大,放大系数的最大值出现在坡肩,在不超过2.0的范围内波动变化。坡顶面上的放大系数随着坡肩距的增大而逐渐衰减。坡体内水平向与竖向放大系数的空间分布特征显著不同,在邻近坡肩和斜坡面的区域内竖向放大系数可高达1.5,高陡边坡的抗震设计中不可忽略竖向放大系数的影响。In this article, dynamics numerical simulations are conducted to investigate the amplification of peak ground acceleration of high-steep rock slope. The relations of amplification factors in the crest and surface of slope with the height and gradient of slope are studied in the presence of harmonic wave and E1 Centro seismic wave. Ac- cording to the computation results, the isolines of horizontal and vertical amplification factor of cross-sectional slope are plotted to analyze the amplification factor distribution in slope. Results indicate that amplification factor does not continuously increase with the rise of slope height. The maximum amplification factor appears in the crest of slope, and fluctuates in a range of no more than 2.0. Amplification factor in the top surface of slope gradually decreases as the distance from slope crest increases. The spatial distribution characteristics are markedly different between hori- zontal and vertical amplification factors in the slope. In the area near the crest of slope, vertical amplification factor is up to 1.5. The influence of vertical amplification factor cannot be ignored in the seismic design of high and steep slope.

关 键 词：高陡边坡 地形放大效应 动力反应 放大系数 地震动参数 

分 类 号：TV223[水利工程—水工结构工程]