水位下降条件下黏性土边坡稳定性的图表法

库（河）岸边坡由于坡体迎水面水位下降经常造成坡体稳定性降低，建立快速评估水位变化条件下的边坡稳定性分析方法具有重要的工程实用价值。基于库（河）水位下降过程及坡体内非稳定渗流条件，通过对ABAQUS程序进行二次开发，发展了考虑地表水-地下水联动作用下的黏性土边坡强度折减有限元分析方法；在分析边坡土性参数、相对渗透比值、边界条件对边坡稳定性影响的基础上，建立了考虑土性参数、相对渗透比值、库水位下降比、坡角等一体化的相对稳定安全系数综合图表表示方法。该方法能够简便、快捷地查出实际涉水边坡在不同工况下的稳定安全系数及设计边坡坡比，可作为现有图表法的有益补充。

Graphic method for stability of clay slopes during water level drawdown

The water level drawdown of reservoir or river often causes the decrease of stability of bank slopes.Establishing a rapid assessment approach for evaluating the stability of slope under the variation of water levels has an important practical significance.Based on the water level drawdown of reservoir or river,and the transient unsteady seepage in clay slope,the program based on shear strength reduction finite element method(SSR-FEM) is developed to compute the factor of safety(FOS) for the slopes under the action of surface water and ground water together.Considering the influences of soil properties,relative permeability ratio and boundary conditions on slopes stability,the relative stability graphic method is presented under the integration parameters of soil properties,relative permeability ratio,drawdown ratio,slope angle,etc.The suggested method can rapidly obtain the FOS of existing slope and the design inclination ratio of planning embankment,and it can also be a helpful supplement for the existing stability charts of simple slope.