Application and Effect of Loading Rates on Coal Sample Failure

In order to evaluate the coal pillar stability in recovery of residual room pillars under different mining rates, this paper studies influence loading rate on mechanical properties body. The uniaxial compression tests samples Yangcheng area at rates were carried out with MTS815 electrohydraulic servo rock mechanics test system. stress-strain curves and evolution characteristics AE signals analyzed. At same time, mechanism damage failure specimens are also discussed. results show following. (1) With increase rate, ultimate stress strain decrease first then increase. (2) Loading has a significant effect adjustment specimens. earlier is, larger range mode changes from shear tensile failure. (3) addition, when increases, evolves continuous dense discrete catastrophe, which indicates that sample is sudden, not conducive maintenance pillar. (4) Finally, specimen structure obtained, improvement measures for velocity working face put forward. reveal provide reference controlling