强度折减法在节理岩质边坡稳定分析中的精度研究

Research on precision of strength reduction method in stable analysis for rock slope

采用有限元强度折减法分析节理岩质边坡的稳定性时,计算精度会受到许多因素(如屈服准则、岩体力学参数、计算网格等)的影响。本文结合算例分析这些因素对强度折减法计算精度的影响。分析结果表明:采用强度折减法分析贯通节理岩质边坡的稳定性时,在关联流动法则下,宜选用Mohr-Coulomb内切圆准则;在非关联流动法则下,宜选用Mohr-Coulomb匹配DP圆准则。此外,当采用Mohr-Coulomb内切圆准则时,可不考虑弹性模量和泊松比对计算结果的影响,并且在单元较少时,就可以得到较为理想的结果。

As carrying on stability analysis of jointed rock slope by the finite element strength reduction,the calculation accuracy is affected by a lot of factors such as yield criterion,rock mechanics parameters,computation net and so on.According to the study of these factors,the analysis results demonstrated that Mohr-Coulomb inscribed circle criteria is a appropriate choice under the associated flow rule;and under the non-associated flow rule,matched DP Mohr-Coulomb criteria is suitable.In ddition,if the former criteria is chosed,the calculation results is independent of the elastic modulus and Poisson＇s ratio,and with a few elements,ideal result can be deduced.