基于滑动面搜索新方法对地震作用下边坡稳定性拟静力分析

BASED ON A NEW METHOD OF SEARCHING FOR SLIDING SURFACE PSEUDO-STATIC STABILITY ANALYSIS OF SLOPE UNDER EARTHQUAKE

采用一种适于任意曲线滑动面的新方法,对地震作用下边坡的稳定性进行拟静力分析。首先,通过算例对比分析验证新方法的可行性。然后,分别在地震竖直和水平加速度系数kv,kH变化时对边坡稳定性进行研究,在kH,kH与kv共同作用下对分层土坡的局部和整体稳定性进行探索,在土层参数变化时对边坡地震稳定性的影响进行分析,从而可得:(1)kH存在一个特殊值使kv的变化对边坡的稳定性影响很小;(2)当kH和kv的增大引起临界滑动面范围增大时,会导致边坡由局部稳定性变为整体稳定性,当kH和kv的增大引起滑动面下滑点上移时,会导致边坡由整体稳定性变为局部稳定性;(3)黏聚力c的变化对滑动面范围影响较大,其对安全系数的影响与地震强度有关;(4)不同土层参数时,kH对边坡稳定性的影响较kv大。

This article adopted a new method of searching for arbitrarily curve sliding surface and analyzed pseudo-static stability of slope under earthquake. First of all, the feasibility of this new method was verified by comparing and analyzing some examples. Then, through this article studied the affect on stability of slope with changes of the vertical seismic acceleration coefficient kH and the horizontal acceleration coefficient kV, explored the effect of kH, kH and kv acting on the local and general stability of layered slope, and analyzed the effects on stability of slope with changes of soil parameters. Some conclusions have been obtained： （1） There is a special value of kH that could make change of kv have little effect on stability of slope. （2） The scope of the calculated critical sliding surface becomes larger with the increases of kH and kv so that it makes the local stability of slope transform into the general stability of that; and at the same time, increases OfkH and kv also cause the lowest point of sliding surface move up so that it makes the general stability of slope transform into the local stability of that. （3） Cohesion e has great effect on scope of sliding surface, and its effect on factor of safety is related with different seismic intensities. （4） With different soil parameters, kH has greater effect on stability of slope than kv.