非稳定渗流下的三维边坡稳定分析

Analysis on Three-dimensional Slope Stability under Unsteady Seepage

在边坡稳定分析中,通常采用二维条分法,但实际上滑坡体常常具有三维特性,因此相应地产生并发展了边坡稳定的三维条柱法。然而,在进行三维稳定分析时通常较少考虑边界水位变化时产生非稳定渗流时的边坡稳定性。以某一工程为例,基于三维简化Bishop法思想,并考虑边界水位变化时的非稳定渗流场,给出了相应的安全系数公式,进行边坡稳定性评价,结果表明,在边界水位变化时,水位下降初始阶段的安全系数值最低,且三维分析方法得到的安全系数较二维分析法有所提高,能更客观地对边坡稳定进行评价。

The 2-D slice method has always been adopted for slope stability analysis,however,the sliding mass usually appears to be three-dimensional characteristics,thus the 3-D slice-column method is correspondingly produced and developed.In three-dimensional slope stability analysis,the unsteady seepage is seldom considered,therefore,based on three-dimensional simplified Bishop’s method,the relevant safety factor formula is given by considering the unsteady seepage,and taking a certain project for example,the slope stability evaluation is carried out.The results indicate that the safety factor is higher by using the 3-D analysis method than that by using the 2-D analysis method,and the safety factor is lowest at the beginning of the head level dropping,so it is more reasonable for the analysis and evaluation of slope stability.