强度准则和失稳判据对有限元强度折减法结果的影响

Influence of strength criterion and collapse criterion on result of strength reduction method of FEM

本文主要研究有限元强度折减法的强度准则和失稳判据问题,从强度折减法基本原理出发,将边坡强度参数进行折减,利用理论分析与数值计算相结合的方法,通过对比分析研究了强度准则与失稳判据的影响。研究表明:在π平面上强度准则围成的圆的半径越大,所得的安全系数则越大。与传统的极限平衡方法的安全系数结果相对比,等面积圆强度准则结果与之相近。3种边坡失稳判据中塑性区贯通判据判断的安全系数偏保守,与Bishop法计算结果较为一致,收敛标准的安全系数偏大。

The paper mainly studied the strength criterion and collapse criterion of FEM with strength re-duction.Starting from the basic principle of strength reduction method ,it reduced some strength parame-ters of slope by reduction factors , combined theory analysis and numerical calculation , and studied some influences of strength rule and collapse criterion through comparison and analysis .The results show that the more the radius of a circle surround by strength criterion on plane ,the greater the safety coefficient of slope becomes .The paper compared the safe coefficient with that from limit equilibrium method and that is near to the result from the strength criterion of equal -area circle .The result indicated that the solution based on the collapse criterion of the plastic region breakthrough is close to Bishop 's solution , the safety coefficient of convergent standard is too large .