水平地震作用下阶梯式复杂土层边坡动力响应及稳定性分析

Dynamic response and stability analysis of ladder-type complicated site soil slope under action of horizontal earthquake effect

针对一阶梯式复杂土层边坡,采用人工修正的加速度时程作为地震输入条件,引入三量放大系数对土坡坡面质点进行地震时程响应分析,并采用Newmark滑块分析法和有限元动力时程分析法计算其稳定性.计算结果表明,在水平地震波作用下,阶梯式土坡坡面质点的水平位移和水平速度随距坡脚的沿坡面距离的增大而增大,且最大值都出现在坡顶,地震加速度放大系数呈不规则分布,受地震累积效应影响,土坡坡面质点三量响应滞后于地震波谱变化;拟静力法计算的安全系数偏保守,有限元动力时程分析法和Newmark法计算后通过处理的各项安全系数结果相近.

In view of the complicated site soil slope,we use the artificial modified acceleration curve as the earthquake input condition,introduce three-volume amplification coefficient on the seismic time history response analysis,and use Newmark sliding block analysis and dynamic finite element time history analysis to calculate its stability. Calculation results show that under horizontal seismic action,bench slope displacement and speed of x to x increase with the increase of distance from slope foot along the slope,that the maximum value appears in the slope,and that the slope seismic acceleration amplification factor distribution is irregular,which are affected by the earthquake cumulative effect,three rock particles quantity response lag behind seismic spectrum changes. The pseudo-static method used to calculate the safety factor is partially conservative,and finite element calculation of dynamic time history analysis method and Newmark after processing through the various safety coefficients can achieve similar results.