基于强度折减法边坡三维稳定性分析

Slope stability analysis based on 3D strength reduction method

有限元强度折减法在边坡稳定分析中应用广泛,在实际工程中,边坡往往具有复杂的几何特征,应当作为三维问题进行分析。本文结合工程实例将强度折减法应用于三维边坡稳定性分析中,对比分析了边坡实际监测变形值和数值模拟土体变形特征,以计算不收敛、位移突变及塑性区贯通判据来判断边坡安全系数,探讨了三维边坡失稳状态和滑动面位置。研究结果表明:实际监测变形规律和数值模拟结果有较好的一致性,在边坡中部坡度较大的部位容易失稳,并且其位移最大,计算不收敛和位移突变判据能够较好地应用于三维边坡稳定性分析中,该边坡的安全系数为1.021,采用强度折减法可以为地质条件复杂的边坡稳定性分析提供一种参考。

Finite element strength reduction method is widely used in slope stability analysis,while slopes usually have complex geometric features in actual engineering,which is usually analysed as a three-dimensional problem.The 3D strength reduction method is applied in a slope stability project.The differences between monitored values of slope deformation and numerical simulation results are compared,the instability state and the sliding surface position of three-dimensional slope are discussed based on the analyzing of safety factor by taking criteria of non-convergence of numerical computations,the mutation of displacement and connectivity of plastic zone.The results show that it is consistent between the actual monitored deformation and the numerical simulation results,the largest displacement occurs in the middle of the steep slope which is easy to fail.The calculation non-convergence and displacement mutation criteria can be applied in 3D slope stability analysis,and the slope safety coefficient is 1.021.The strength reduction method could be referred for the slope stability analysis with complex geological conditions.