3D numerical modeling of strength in fractured rock mass

Abstract

Characterization of strength of fractured rock mass is very important in different engineering rock works such as dam foundation, rock slope analysis and underground excavation projects. Compared to the continuum media, three dimensional stochastic Discrete Fracture Network (DFN) modeling enjoys more realistic fracture patterns. Among the other numerical modeling, Discrete Element Method (DEM) could also simulate such complicated DFN models when mechanical properties of both intact rock and rock fractures take into account. A large number of cubic 3D, DFN models with different side lengths were generated using fracture mapping results from Chamshir Dam Site in Iran, and then subjected to uniaxial, conventional, true and extensional triaxial compressive stress loading (under constant loading velocity regime). Uniaxial Compressive Strength of different model sizes were evaluated and Representative Elementary Volume (REV) was approximated. Compatibility of both theoretical and empirical failure criteria with results were also examined when all or just minimum and maximum principal stress components are considered.