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Abstract In order to investigate the problem of rock fracture propagation and arrest under mixed-mode I and II dynamic loading，single cleavage semi-circle compression(SCSCC) plate specimens of sandstone were subjected to dynamic impact by a split Hopkinson pressure bar(SHPB). Numerical simulations were used to study the fracture propagation path under mixed mode dynamic loading. In order to verify the reliability of the numerical simulation，dynamic finite difference analysis was applied to a finite plate with a central crack subjected to impact tension at the boundary. For the SHPB tests，the measured strain at the incident bar was compared with the strain obtained from the numerical simulation. The results show that：(1) The numerical model produced outcomes that are consistent with published results. The strain values at the incident bar from numerical simulations and experiments agree extremely well with each other，suggesting the feasibility of using numerical methods to model SHPB tests. (2) The crack propagation path from the numerical simulation agrees reasonably well with the SHPB test results. (3) During the fracture propagation in SCSCC specimens，the crack tip suffers some instantaneous arrests but eventually will propagate towards the central axis(maximum stress zone) of the specimen. (4) SCSCC specimens provide a suitable geometry to study dynamic rock fracture problems. They can be easily used for mixed-mode I and II loading conditions and will provide an effective tool for subsequent research on crack propagation arrest.
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2015, Vol. 34 
