Numerical simulation of pore structure stress characteristics of coal and rock mass

Authors

WANG Gang, Mining Disaster Prevention and Control-Ministry of State Key Laboratory Breeding Base, Shandong University of Science and Technology, Qingdao 266590, China; College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China
JIANG Chenghao, College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China
CHEN Xuechang, College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China

Abstract

In order to explore the stress distribution around the pores of coal and rock mass under different loading modes, the skeleton model of coal and rock mass with different pore shapes was constructed through CT three-dimensional reconstruction technology, and uniaxial and triaxial compression experiment simulations were conducted using ABAQUS software. The results showed that under uniaxial compression, the upper and lower regions of spherical pores showed tensile stress concentration, while the left and right regions showed compressive stress concentration. The stress concentration types in the long and short axis of elliptic pores were distinct with different dip angles. Under uniaxial compression, axial loading velocity affected the maximum values of Mises stress and σ₁ stress around spherical pores. In the process of triaxial compression, the pore structure still went through four stages of compaction, elasticity, plasticity and failure. The lower confining pressure made the "stress-strain" curve and "stress-time" curve highly coincide in the elastic stage. This study provides a new method for the study of coal and rock mechanics from the microscopic point of view.

Keywords

CT three-dimensional reconstruction, pore structure, numerical simulation, uniaxial compression, three axis compression

DOI

10.3969/j.issn.1001-1986.2021.01.006

Recommended Citation

WANG Gang, JIANG Chenghao, CHEN Xuechang, et al. (2021) "Numerical simulation of pore structure stress characteristics of coal and rock mass," Coal Geology & Exploration: Vol. 49: Iss. 1, Article 7.
DOI: 10.3969/j.issn.1001-1986.2021.01.006
Available at: https://cge.researchcommons.org/journal/vol49/iss1/7

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