有限元强度折减系数法计算土坡稳定安全系数的精度研究

The feasibility study of strength-reduction method with FEM for calculating safety factors of soil slope stability

有限元强度折减系数法在边坡稳定分析中的应用正逐渐受到人们的重视。本文较为全面地分析了土体屈服准则的种类、有限元法自身计算精度以及H (坡高 )、 β (坡角 )、C (粘聚力 )、Φ (摩擦角 )对折减系数法计算精度的影响 ,并给出了提高计算精度的具体措施。通过对 10 6个算例的比较分析 ,表明折减系数法所得稳定安全系数比简化Bishop法平均高出约 5 7% ,且离散度极小 ,这不仅验证了文中所提措施的有效性 。

The shear strength reduction method(SRM) with FEM on analysis of slope stability is increasingly applied. All round analyses were made for the influence on computation precision caused by different soil yield criterions, FEM accuracy, slope height, cohesion and friction angle. Measures to improve the precision were put forward. Computation and comparison were made for 106 cases. The results show that the safety factors calculated with SRM were averagely exceeding those with Bishop simplified method at 5 7% and the scatter was small. The proposed measures for improving precision in valid and the method of FEM-SRM to analyzing slope stability can be applied.