有限元强度折减法在土石坝边坡稳定分析中的应用

在指出传统边坡稳定分析方法的缺点和不足的同时,重点研究了有限元强度折减法的理论背景、突出优势、计算结果的影响因素、边坡失稳判据方法,探讨了该方法应用于土石坝边坡稳定分析中的可行性。采用摩尔-库仑屈服准则、非关联流动法则,在已知渗流场的前提下,基于有效应力原理逐步进行强度折减,直至满足力和位移不收敛的失稳判据,从而得到相应强度折减法的土石坝坝坡稳定安全系数。结果表明,无论是关键滑裂面位置还是最小安全系数,有限元强度折减法的计算结果与刚体极限平衡法的计算结果都相当接近,从而表明此法在土石坝边坡稳定分析中的可行性,拓宽了该法的应用范围。

FEM Strength Reduction and Its Application in Rockfill Dam Slope Analysis

The shortcomings of traditional slope stability analysis are pointed out, the theoretic backgrounds, dominant superiorities, and influence factors of calculation outcome, slope failure criterion and its application of FEM strength reduction method are studied,the feasibility of application FEM strength reducting method to rockfill dam slope analysis is discussed. Based on Mohr-Coulomb yield criterion, non-association flow law, the effective stress principle and the known seepage field, rockfill dam slope stability factor is obtained through strength reduction step by step until satisfying force and displacement failure criterion. Calculation results show that the critical slip location and minimum safety factor of FEM strength reduction method is consistent with classical limit equilibrium method. Case study indicates the feasibility of FEM strength reduction in rockfill dam slope analysis, and application scope of this method is enlarged.