基于OpenMP的非连续变形分析并行计算方法

非连续变形分析（DDA）方法严格满足平衡要求和能量守恒，具有完全的运动学及数值可靠性，但对大规模岩土工程问题的数值模拟耗时太长，尤其是线性方程组求解，并行计算可以很好地解决该问题。首先基于DDA方法的基本理论，阐述了适用于DDA方法中的基于块的行压缩法和基于“试验-误差”迭代格式的非零位置记录；其次，引入块雅可比迭代法并行求解DDA方法的线性方程组，并改进了相应的非零存储方法；最后，基于OpenMP实现了DDA线性方程组求解并行计算，并将其应用于地下洞室群的破坏过程分析，以加速比为并行效率的指标评价，结果表明，该并行计算策略可以极大提高DDA的计算效率，而且适合各种规模的问题。

Parallel computing method for discontinuous deformation analysis using OpenMP

The discontinuous deformation analysis (DDA) strictly meets balance requirements and energy conservation, and has complete kinematics and numerical reliability. However, the computation time of simulating large-scale geotechnical engineering is too long, especially for solving linear equations; the parallel computing will be a good solution to the problem. Firstly, two contents of non-zero storage in DDA have been described. One is the block compressed sparse row method, and the other is the iterative scheme of non-zero position recording based on the trial-error. Furthermore, we have introduced the block Jacobi iterative method to parallel solving linear equations of DDA, and improved the non-zero storage method. Finally, benefit from the sub-matrices storing, parallel computing of the DDA has been achieved based on Opening Multi-Processing. The improved DDA program has been used to simulate the failure process of the underground caverns; the speedup is obtained to evaluate the parallel efficiency. The results demonstrate that the parallel computing strategy can greatly improve the computational efficiency of DDA for the problems with various sizes. The investigations of this paper will promote DDA to the engineering simulation.