DEM Simulation of Brazilian Tensile Failure of Hard Rock in Consideration of Loading Condition

Nakashimaa, S. (Yamaguchi University) | Taguchi, K. (Yamaguchi University) | Funatsu, T. (Advanced Industrial Science and Technology) | Shimizu, N. (Yamaguchi University)

OnePetro 

ABSTRACT


The Particle Flow Code (PFC), a simulation code based on the distinct element method (DEM), is an effective numerical tool for simulating the failure process of hard rock. By introducing contact- and parallel-bond models and clump particle model, the code has become better able to express the ratio of uniaxial compressive strength to tensile strength of hard rock. On the other hand, a problem has been pointed out, namely, that PFC simulations with the clumped particle model cannot reproduce rapid strain-softening behavior in Brazilian tensile tests. In addition, cracks propagate too widely in the specimens, differently from the cracks observed in the experimental data. Attributing the above problem to the loading configuration, some two-dimensional PFC simulations were conducted in Brazilian tests under several loading conditions in this study. Strip loading (line loading in two dimensions) and line loading (point loading in two dimensions) were taken into consideration. From the simulation results, point loading was found to be effective for expressing rapid strain-softening behavior and crack propagation in Brazilian tensile tests.