Acceleration of contact detection between arbitrarily shaped polyhedra based on multi-cover methods in three dimensional discontinuous deformation analysis

摘要

Three-dimensional discontinuous deformation analysis (3D DDA) can address the large-displacement dynamic responses in rock engineering. However, the efficiency of contact detection is the bottleneck of 3D DDA. This study automatically generates a multi-shell cover (MSC) system and develops a novel multi-cover search (MCS) algorithm for 3D cases. MSC expedites contact detection by dividing the geometric elements of polyhedra into several groups, and MCS accelerates contact detection by efficiently selecting potential contacts using the neighbor relations between faces of polyhedral blocks. These methods increase the accuracy of the rough search in the neighbor search process and improve contact pattern identification. As a result, the number of delicate checks between the geometric elements of two neighbor blocks is greatly reduced. Some numerical tests in rock engineering are used to verify that these two multi-cover methods can accelerate contact detection between arbitrarily shaped polyhedra in 3D DDA.