关键词: 煤岩, 霍普金森压杆, HJC本构模型, 冲击破坏

Abstract: By using the Holmquist-Johnson-Cook (HJC), the constitutive model, the Φ50 mm split Hopkinson pressure bar (SHPB) tests for coal have been numerically simulated with the finite element analysis software LS-DYNA. The simulation results have reoccurred the stress waves shape, stress variation and the destruction process of coal specimen during the SHPB tests. By contrast, it has been found that the numerical simulation is similar to the experiment results, and that the dynamic destruction process of coal specimen during the SHPB tests can be reoccurred reasonably with HJC constitutive model. The numerical simulation has shown that：1) The coal specimens have been destroyed firstly from around with the destruction mode of splitting failure in the axial direction mainly. 2) When the impact velocity is about 3 m/s, the destruction of the coal is caused by both compression and tensile; When impact velocity is about 9 m/s, the destruction of the coal is caused mainly by compression. 3) The destruction of the coal is out of sync with the peak stress: when the dynamic load is lower, the destruction of coal specimens lags behind the stress peak; when the dynamic load is higher, the destruction of coal specimens is ahead of the stress peak.

Key words: coal, split Hopkinson pressure bar, Holmquist-Johnson-Cook constitutive model, impact damage