强度折减计算中的可视化分析与失稳标准比较

Comparison of instability criteria with visual analysis in SRFEM

为了探讨强度折减有限元计算中不同失稳标准的适用性和差异,基于实时可视化思路,研发了相应的可视化程序,在强度折减有限元计算中完成了3种失稳标准与强度折减系数之间关系的实时可视化视图显示技术,然后对3个较为复杂的边坡进行了数值计算分析和比较研究。研究结果表明:采用强度折减有限元法与计算机可视化技术结合可直观分析滑坡的滑动面和稳定性;uF曲线的最大曲率出现位置比ε-F曲线的最大曲率出现位置稍早,而ε-F曲线的最大曲率出现位置又比N-F曲线的最大值出现位置稍早;对于具有局部滑动面存在的边坡和形状复杂的边坡,在强度折减有限元计算中采用不同失稳标准得出的安全系数有一定差异,算例中最大差异可达到22.6%。

Abstract： In order to explore the applicability and discrepancy of different instability criteria in computation with strength reduction finite element method, based on the thought of real-time vis- ual analysis, this paper developed the corresponding visual programs, and proposed the real-time visual display technique of relationship between three instability criteria and the strength reduc- tion factor in computation with strength reduction finite element method, and then made the nu- merical computation analysis and comparative study on three complicated slopes. The results indi- cate that with the combination of the strength reduction finite element method and the computer visual technique, the sliding surface and the stability of a slope can be analyzed intuitively. The appearance position of maximum curvature of u-F curve is earlier than that of maximum curvature of ε-F curve, while the appearance position of maximum curvature of ε-F curve is earlier than that of maximum curvature of N-F curve. For slopes with local sliding surface or complicated shapes, safety factors are somewhat different because of employing the different instability criteria in the computation with strength reduction finite element method and the largest discrepancy can reach 22.6% in some cases. 5 tabs, 16 figs, 12 refs.