Parallel analysis of two-dimensional finite-discrete element method based on OpenMP

The coupling method of finite- discrete element method(FDEM) by Munjiza is an effective procedure for simulating rock failure. In order to overcome the mesh dependency, it is necessary to partition the rock mass into very small triangular elements; and the elements do not share the nodes, creating a vast number of variables, therefore, the calculation is very time consuming. The method overcomes competition among the existing data in the parallelization and balances loads in a parallel program. A set of strategies for parallelizing serial programs are proposed, determining the hot zones of the serial program, then parallelizing the hot zones as far as possible and using as many private variable as possible to circumvent competition. If there are still data competition among the treads, dynamic lists can be used to store these competitive data. Finally, the data stored in the various dynamic lists are merged outside the parallel zones. Data competition is accordingly avoided with no use of critical section or lock; and the effect of the program parallelization is hence increased. By the proposed method, the parallel version of the FDEM program is developed, which can be used to solve large-scale problem. A numerical example about cliffs collapse shows the effectiveness of the proposed method.