Study on the Rock Size Effect of Quasistatic and Dynamic Compression Characteristics

To study the size effect of rock under quasistatic and dynamic conditions, changes in compressive strength with change specimen are measured. Cylindrical granite specimens length-diameter ratios range 0.5?1 used for uniaxial compression tests using an RMT testing machine SPHB impact machine. Under loading, failure modes different different. The larger structure is, greater probability defects such as joints micro cracks is smaller influence on distribution a three-dimensional stress state is. decreases increasing ratio. Using improved Weibull formula, expressed by volume, calculated volumes similar to from tests. strengths similar, mode that loading. Soon after crack appears specimen, splits. As decreases, fragments approach millimeter scale. By improving formula considering variation strain rate caused rocks introducing critical related parameters, results experimental obtained. based can accurately describe laws.