Rock mass stability analysis based on contact mode using DDA

This paper firstly introduces the process in contact calculation between blocks of Discontinuous Deformation Analysis (DDA) and validates its precision. The contact mode judged after Open-Close iteration is also accurate since the contact force calculation is based on the rigorous equilibrium equations. Therefore, the detachment between two neighboring blocks along joints could be identified quickly and accurately. Based on this, we propose a new approach to search the failure surface in rock mass automatically based on contact mode information. At last, combining with Shear Strength Reduction method (SSR), DDA has been used to analyze the stability of model rock slope using the new proposed failure criterion. Comparing with analytical solution, it is shown that our new approach is applicable and accurate.