Mechanical Behavior of Granite with Different Grain Sizes After High-Temperature Treatment by Particle Flow Simulation

Understanding thermo-mechanical properties of granites with different grain sizes is of great significance for the site selection of high-level radioactive waste disposal. In this paper, a cluster model was used to investigate the uniaxial compressive behaviors of granite specimens with different grain sizes. It turns out the results of simulation match experimental results. Grain size has a significant effect on the mechanical behaviors of granite. Macro-cracks can be easily observed in the coarse granite specimens after high-temperature treatment. However, the number of inter-cracks in the granite specimens decreased with increasing the grain sizes. When T >= 600 degrees C, main cracks were not observed in the compressed specimens, and the ultimate failure modes were mostly dominated by thermally induced cracks. The isolated grains can be observed in the coarse granite specimens. The reduction in the uniaxial compressive strength of the coarse-grained granite specimens was lower than that for the fine-grained granite specimens.