In order to study the impact failure characteristics of strain rate and confining pressure on coal samples,the Split Hopkinson Bar experimental device was used to carry out the dynamic impact experiments of 15 groups of coal samples with strain rate of 60 s-1 to 110 s-1 and axial confining pressure of 12 MPa,15 MPa,18 MPa.Combined with the experimental results,the simulation of failure and instability of goaf under impact load was explored,and the applicability of the influence of strain rate-confining pressure on the numerical simulation of rock burst disasters was judged according to the numerical simulation results.The results show that the impact failure of coal samples shows a significant strain rate effect,and the dynamic compressive strength of coal samples is proportional to the loading strain rate.Confining pressure conditions from 12 MPa to 18 MPa have a weakening effect on the strain rate effect and compressive strength of coal,and under the same impact pressure,the coal sample crush becomes more significant with the increase of confining pressure.The simulation results are consistent with the experimental results,so the strain rate effect and confining pressure effect are applicable to the numerical simulation of rock burst disaster.
关键词
冲击地压/三轴围压/应变率效应/围压效应/数值模拟
Key words
rock burst/triaxial confining pressure/strain rate effect/confining pressure effect/numerical simulation
维普
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