Microcrack Propagation-Based Damage Mechanics Model of Rock

doi:10.12068/j.issn.1005-3026.2022.12.016

Abstract

Abstract: Through studying the cracking and propagation law of compressive-shear cracks in rock under remote stress field， a new calculation model for the mode-I stress intensity factor at wing crack tip was proposed by considering the interaction of wing cracks. Based on the modified wing crack propagation model， considering the damage evolution on the number of the activated microcracks， a microcrack propagation-based damage model for rock was established by combining the relationship between macro-micro definition of rock damage. Finally， the theoretical curves of proposed damage model were compared with the experimental curves. The results showed that the modified wing crack propagation model can not only accurately predict the cracking angle of wing crack， but also simulate the whole range of variation of wing crack length from being extremely short to very long. The microcrack propagation-based damage model can not only continuously describe the stress-strain curves under different confining pressures， but also predict the peak strength well.

Key words: rock mechanics; wing crack; macro-micro damage; stress-strain curves; stress intensity factor

CLC Number:

TU45

PENG Zhi-xiong， ZENG Ya-wu. Microcrack Propagation-Based Damage Mechanics Model of Rock[J]. Journal of Northeastern University(Natural Science), 2022, 43(12): 1784-1791.

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