Experimental study on mechanical properties of coal under different gas pressure

doi:10.16265/j.cnki.issn1003-3033.2021.03.013

Abstract

Abstract: In order to study influence of gas on mechanical properties of coal, a uniaxial compression test of coal under different gas pressure was designed. Change trend of coal samples' mechanical parameters and deformation characteristics along with gas pressure was studied to explore influence mechanism of gas on their mechanical properties, their parameters under uniaxial compression were obtained, and failure mode was recorded. The results show that with increase of gas pressure, compaction stage of stress-strain curve increases while elastic stage decreases, and the curve decreases slowly after instability failure. Meanwhile, compressive strength and elastic modulus decrease monotonously while peak strain increases monotonously. Cracks of coals with no gas produced under load are relatively simple, but gas-containing coal samples, after being damaged under load, see obvious main cracks and multi-directional bifurcation cracks as well as partial coal body shedding.

Key words: gas pressure, mechanical properties, uniaxial compression, deformation and failure, effective stress

CLC Number:

X936

ZANG Zesheng, LI Zhonghui, NIU Yue, LIU Shuaijie, SONG Jingjing, ZHANG Quancong. Experimental study on mechanical properties of coal under different gas pressure[J]. China Safety Science Journal, 2021, 31(3): 90-95.

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