Influence mechanism of contact surface mechanical properties on mechanical behavior of coal rock combination

被引:0
|
作者
Fan Y. [1 ,2 ]
Xiao X. [1 ,2 ]
Ding X. [1 ,2 ]
Xu J. [1 ,2 ]
Wang A. [3 ]
Lei Y. [4 ,5 ]
机构
[1] School of Mechanics and Engineering, Liaoning Technical University, Fuxin
[2] Liaoning Key Laboratory of Mining Environment and Disaster Mechanics, Liaoning Technical University, Fuxin
[3] Institute of Disaster Rock Mechanics, Liaoning University, Shenyang
[4] China Coal Technology & Engineering Group Corp., Shenyang Research Institute, Fushun
[5] State Key Laboratory of Coal Mine Safety Technology, Fushun
来源
关键词
coal rock combination; contact surface of coal rock; end-face effect; mechanical behavior; rock burst tendency;
D O I
10.13225/j.cnki.jccs.2022.0540
中图分类号
学科分类号
摘要
The uniaxial compression test of coal and rock combination was carried out in order to clarify the influence mechanism of the contact surface mechanical properties on the rock-burst tendency of the coal rock combination, and the contact surfaces with four different mechanical properties were considered. The variation laws of strength, elastic modulus, strain softening phenomenon, acoustic emission characteristic signal, energy accumulation and dissipation characteristics, and impact tendency of coal rock combination were analyzed. The influence mechanism of end face effect caused by the bonding properties and failure of contact surface on local deformation characteristics and strength of coal and rock was studied. The results show that the mechanical properties of the contact surface have a certain influence on the mechanical properties of the coal rock combination. The complete contact surface enhances the strength and elastic modulus of the coal rock combination, improves the elastic energy accumulation ability, inhibits the sample fracture in the pre-peak stage, and weakens the strain softening stage after the peak. The failure of the contact surface reduces the influence of the end-face effect, improves the failure degree of the coal rock combination, prolongs the post-peak strain softening process, and the strain energy density in the pre-peak stage is mainly plastic dissipation. The mechanical indexes of unbonded coal rock combination samples are lower than that of others. The constitutive relationship of coal rock combination is established, and the strength estimation method considering the contact surface failure, and the determination method of contact surface fracture are proposed. The theoretical calculation results are consistent with the experimental results. With the improvement of mechanical properties of rock coal interface, the proportion of elastic energy of combined coal increases, and the proportion of plastic property decreases. The influence law of the mechanical properties of rock coal contact surface on the rock burst tendency of coal rock combination is clarified. It is considered that the relative mechanical properties between the contact surface and coal is an important factor which causes the conflict of various indexes of coal rock combination rock burst tendency. © 2023 China Coal Society. All rights reserved.
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页码:1487 / 1501
页数:14
相关论文
共 26 条
  • [1] XIAO Xiaochun, FAN Yufeng, WU Di, Et al., Study on relationship between mechanical properties and acoustic emission-charge signals of combined coal-rock[J], Journal of Safety Science and Technology, 14, 2, (2018)
  • [2] LU Caiping, Intensity weakening theory for rockburst of compound coal-rock and its applocation, (2008)
  • [3] ZUO Jianping, XIE Heping, MENG Bingbing, Et al., Experimental research on loading-unloading behavior of coal-rock combination bodies at different stress levels, Rock and Soil Mechanics, 32, 5, pp. 1287-1296, (2011)
  • [4] ZHANG Chenyang, Research of the influence laws of bottom coal thickness on roadway floor burst start-up, (2018)
  • [5] YANG Lei, GAO Fuqiang, WANG Xiaoqing, Et al., Study on energy evolution low and failure mechanism of coal-rock combined secimen[J], Journal of China Coal Society, 44, 12, pp. 3894-3902, (2019)
  • [6] BAI Jinzheng, Rock burst mechanism in bearing coal pillar under hard roof-coal-floor structure and its application, (2019)
  • [7] CHEN Shaojie, YIN Dawei, ZHANG Baoliang, Et al., Mechanical characteristics and progressive failure mechanism of roof-coal pillar structure[J], Chinese Journal of Rock Mechanics and Engineering, 36, 7, pp. 1588-1598, (2017)
  • [8] ZHAO Yangfeng, LI Bing, ZHANG Chao, Et al., Experimental study on charge induction and microseismic laws of coal and rock with different combination ratios[J], Journal of Safety Science and Technology, 15, 1, pp. 107-112, (2019)
  • [9] CHANG Yue, ZHANG Yaping, LI Jizu, Et al., Experimental study on mechanical properties and permeability evolution law of coal-rock combination[J], Safety in Coal Mines, 48, 6, pp. 28-31, (2017)
  • [10] FAN Yufeng, XIAO Xiaochun, XU Jun, Et al., Mechanical properties of coal rock combinations and evaluation of impact tendency considering effects of the height portion of coal[J], Journal of China Coal Society, 45, S2, pp. 649-659, (2020)