Improvement in Definition of Joint Parameters in Discontinuous Deformation Analysis

To improve the accuracy of value assignment for the joint parameters in the discontinuous deformation analysis (DDA) program, an improved method for definition of the joint parameters was proposed based on the definition of the joint parameters in the DDA original program. First, according to the physical and mechanical properties of joints, the problem of inconsistency regarding the definition of the joint parameters in the original DDA was analysed. Second, because the joint attribute was determined by the two structural planes of a joint, the joint parameters in the program were redefined. Last, the code for parameter assignment was modified and complemented, and the process flowchart was provided. An example of the relative sliding of two blocks was studied to examine the improved DDA program. The results show that, when the mechanical parameters of blocks 1 and 2 are exchanged, the joints between the two blocks are still joints with the same nature. Under both conditions, the velocity and displacement of Block 1 remain the same. The results also indicate that the improved DDA program can achieve unity of the parameter assignment of the joints.