强度折减法在边坡稳定性分析中的应用

以一均质土坡为例,首先采用有限元整体强度折减法计算,在此基础上分别选取塑性剪切应变率大于2.0e-5和塑性区为局部强度折减法的折减范围,通过局部强度折减得到边坡滑裂带分布和稳定安全系数,分析不同折减范围下边坡稳定安全系数、特征点位移以及滑裂带的变化规律。比较天然状况和稳定渗流状态下局部强度折减和整体强度折减的计算结果。结果显示:两种方法得到的稳定安全系数基本一致,但折减范围的选择对计算结果影响很大,折减塑性剪切应变率大于2.0e-5的范围得到的稳定安全系数较小。

Application of slope stability based on local strength reduction method

Stability analysis of the slope has been finished by global and local strength reduction method.For a homogeneous soil slope,calculation has been done firstly by global strength reduction method,so two reduction regions were adopted,one was greater plastic shear strain rate than 2.0e^-5 and the other was plastic flowing region,the sliding surfaces and the safety factors of slope were achieved by local strength reduction method,and the changing rule of the safety factors and the displacement of key points and the slip zone under different reduction scopes were analyzed.The results from the global strength reduction and the local strength reduction under the condition of the natural condition and steady seepage condition were compared with each other.The results showed that safety factors were almost the same,but the reduction region effected calculation results were significant,the stability safety factor by the reduction range of greater plastic shear strain rate than 2.0e^-5 was smaller.The results can provide reference for selecting the appropriate reduction regions with finite element strength reduction method.