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DDARF成功实现了模拟岩体裂纹萌生、扩展、贯通、破碎的全过程,但缺乏有效的锚杆失效判据和程序计算收敛判据。针对锚杆体的拉断破坏,采用最大拉应力准则,并在VC++平台下程序实现;针对锚杆体的滑脱失效,采用莫尔–库仑准则对灌浆体强度进行判断,并程序实现;针对程序计算的收敛判据,采用前后两步位移差与当前步位移比值小于某个极小值的方法,并程序实现,同时考虑了松弛因子对收敛的影响。将DDARF中锚杆的失效判据及程序计算收敛判据与室内试验进行对比,并应用到工程算例中。结果表明,DDARF中锚杆的失效判据和程序计算的收敛判据是有效的,能提高计算的效率和精度,为工程中特殊部位的支护提供参考;合理的松弛因子有助于程序计算的收敛,作者建议DDARF中松弛因子取值1.4～1.8较为合理。
DDARF has successfully realized the whole process of simulating the initiation, propagation, penetration and crushing of rock mass, but it lacks the effective criterion of bolt failure and the convergence criterion of program calculation. According to the pullout failure of anchor body, the maximum tensile stress criterion is adopted and the program is implemented under the VC ++ platform. For the failure of anchor body, the strength of grouting body is judged by Moiré-Coulomb criterion and the program is implemented. The convergence criterion is calculated by using the method that the ratio of the displacement difference between the two steps before and after the step and the current step is less than a certain minimum value, and the program is implemented. Meanwhile, the influence of the relaxation factor on the convergence is considered. The criterion of failure of the anchor in DDARF and the convergence criterion of program calculation are compared with those of the indoor test and applied to the engineering study. The results show that the failure criteria of DDARF and the convergence criterion of program calculation are effective, which can improve the efficiency and accuracy of the calculation and provide a reference for the support of special parts in engineering. The reasonable relaxation factor helps the calculation of the program The author suggests that the relaxation factor in DDARF should be 1.4 ~ 1.8.