A statistical damage constitutive model for rock based on modified Mohr–Coulomb strength criterion

Autor: Zhixiong Peng, Xi Chen, Yang Ye, Yawu Zeng
Rok vydání: 2021
Předmět:
Zdroj: Arabian Journal of Geosciences. 14
ISSN: 1866-7538
1866-7511
DOI: 10.1007/s12517-021-08862-x
Popis: The study on strength criterion and constitutive relationship for rock in the deep strata is an essential and paramount requirement for the analysis and design of deep underground engineering. Traditional strength criteria were generally proposed based on rock mechanics tests under low confining pressure and overestimated the strength of rock under high pressure. This is a significant safety risk for the construction of deep underground projects. Hence, a modified Mohr–Coulomb strength criterion was proposed by employing the critical state concept for rock and rock critical state coefficient. Under the assumption that the meso-element strength of rock follows the two-parameter Weibull distribution and meso-element failure follows the modified Mohr–Coulomb strength criterion, a new statistical damage constitutive model for rock in the deep strata was proposed. The modified Mohr–Coulomb strength criterion and the statistical damage constitutive model were verified with the results from the conventional triaxial compression test of quartz sandstone. The results show that the proposed damage constitutive model can well grasp the nonlinear strength properties and simulate the stress–strain relationships under different confining pressures, and its parameters have definite physical meaning. Moreover, the parameters of the proposed model, obtained from triaxial strength tests performed at low confining pressure (the confining pressure is less than 20 MPa), can be directly used to accurately predict the triaxial strength and the stress–strain relationships of the tested red sandstone in this study at higher confining pressure.
Databáze: OpenAIRE
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