Considering that an irregular ubiquitiformal fracture surface is resulted from the heterogeneity of rock material, a numerical simulation on the extension of a ubiquitiformal crack in rock material was carried out by using the ABAQUS software, together with the Weibull distribution characterization of the heterogeneity of material properties.The ubiquitiformal crack extension of rock material under dynamic tensile loading was analysed and the complexity of the fractured profile was calculated by using the box counting dimension.The numerical results were in good agreement with previous experimental data.The results of the crack extension path and the complexity of the fracture surface under different strain rate show that the complexity decreases with the increase of strain rate.Furthermore, from the analysis of ubiquitiformal fracture energy, it is found that the energy release rate increases with the increase of strain rate.Under lower strain rate,the crack propagates in the direction of minimum energy dissipation, while, with the increase of strain rate, the crack penetrates through the higher fracture energy element and propagates along the self-similar extension direction.These results imply that the strain rate effect on the extension of the ubiquitiformal crack can be induced by the heterogeneity of rock material, which could help to understand the mechanism of ubiquitiformal fracture.
李竟艳,高文学,宋肖龙. 岩石材料动载下泛形裂纹扩展数值模拟[J]. 振动与冲击, 2018, 37(22): 88-91.
LI Jingyan, GAO Wenxue, SONG Xiaolong. Numerical simulation on the extension of a ubiquitiformal crack of rock materials under dynamic loading. JOURNAL OF VIBRATION AND SHOCK, 2018, 37(22): 88-91.
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