Rock and Soil Mechanics ›› 2023, Vol. 44 ›› Issue (S1): 387-398.doi: 10.16285/j.rsm.2021.0797

• Fundamental Theroy and Experimental Research • Previous Articles     Next Articles

Fracture mechanism of coal-rock combination under unilateral confinement compression

PENG Yang1, GAO Yong-tao1, WANG Wen-lin2, FUER Kate1, WEN Jian-min1, ZHOU Yu1   

  1. 1. Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mine, University of Science & Technology Beijing, Beijing 100083, China; 2. Shaanxi Huabin Coal Industry Co., Ltd., Xianyang, Shaanxi 713500, China
  • Received:2021-05-28 Accepted:2021-10-09 Online:2023-11-16 Published:2023-11-19
  • Supported by:
    This work was supported by the Young Scholars of National Natural Science Foundation of China (51504016) and the Fundamental Research Funds for the Central Universities (FRF-IDRY-20-024).

Abstract: The research of the coal-rock system composed of deep coal seams and surrounding rock masses has become one of the popular research directions in deep mining. In this study, the L-shaped mold is used to carry out the unilateral confinement compression test on the rock-coal-rock combination, and the digital image correlation technology (DIC) and the particle flow PFC2D are used to analyze the test strength, failure characteristics and crack distribution of the coal-rock combination. (1) The main strain areas of coal-rock combination are all concentrated on the free side of the sample coal seam. (2) Under unilateral confinement, the joint restriction of the two rock layers on the coal seam decreases as the height-to-width ratio of the coal seam increases. The damage of the sample is gradually transferred from the middle of the coal seam to the end of the coal seam. (3) When the ratio of coal-rock combination is 1:1:1 and 1:2:1, the failure mode of the calculation model shows a <-shaped fracture, which appears on the free side in the middle of the coal seam. When the rock-to-rock ratio is 1:4:1, the macroscopic damage gradually shifts to the middle and upper part of the coal seam, and evolves into shear failure. (4) The microscopic cracks of the calculation model are mainly located on the free side, which appear as tensile cracks. The number of the tensile cracks inside the model are about 4.5 times that of the shear cracks.

Key words: coal-rock combination, unilateral confinement compression, digital image correlation technology, particle flow code, fracture mechanism

CLC Number: 

  • TU 452
[1] SONG Shuo, REN Fu-qiang, CHANG Lai-shan, . Experimental investigation on the failure and acoustic emission characteristics of coal-rock combination with prestressed bolt [J]. Rock and Soil Mechanics, 2023, 44(S1): 449-460.
[2] WANG Kai, FU Qiang, XU Chao, AI Zi-bo, LI Dan, WANG Lei, SHU Long-yong, . Numerical simulation of interface mechanical effects of primary coal-rock combination [J]. Rock and Soil Mechanics, 2023, 44(S1): 623-633.
[3] RU Wen-kai, HU Shan-chao, LI Di-yuan, MA Jin-yin, ZHANG Chen-xi, LUO Ping-kuang, GONG Hao, ZHOU Ao-hui . Energy evolution of unloading confining pressure and dissipative energy damage constitutive model of coal-rock combination [J]. Rock and Soil Mechanics, 2023, 44(12): 3448-3458.
[4] XU Hao-chun, JIN Ai-bing, ZHAO Yi-qing, CHEN Zhe, . Numerical study on Brazilian splitting of heat-treated sandstone under different contact angles [J]. Rock and Soil Mechanics, 2022, 43(S2): 588-597.
[5] HU Xun-jian, BIAN Kang, LIU Jian, XIE Zheng-yong, CHEN Ming, LI Bing-yang, CEN Yue, . Particle flow code analysis of the effect of discrete fracture network on rock mechanical properties and acoustic emission characteristics [J]. Rock and Soil Mechanics, 2022, 43(S1): 542-552.
[6] CHENG Jian-long, ZOU Qing-you, YANG Sheng-qi, LI Xiao-zhao, LIANG Quan, QU Lei, MEI Yan, . Simulation of indentation behavior of TBM disc cutter and failure mechanism of hard rock assisted by hydraulic precutting kerfs [J]. Rock and Soil Mechanics, 2022, 43(8): 2317-2326.
[7] SHI Dan-da, YU Kuai, MAO Yi-yao, YUAN Yuan, HAO Dong-xue, HU Wei, . Experimental study on the uplift behavior and soil deformation characteristics of the double-blade screw anchor in loose sand [J]. Rock and Soil Mechanics, 2022, 43(11): 3059-3072.
[8] XU Hua, ZHOU Ting-yu, WANG Xin-yu, ZHANG Jie, ZHANG Xiao-bo, LIU Yu-chen, . Compression test and numerical simulation research on improved red beds subgrade fillers in Sichuan-Tibet Railway [J]. Rock and Soil Mechanics, 2021, 42(8): 2259-2268.
[9] CUI Peng-bo, ZHU Yong-quan, LIU Yong, ZHU Zheng-guo, PAN Ying-dong, . Model test and particle flow numerical simulation of soil arch effect for unsaturated sandy soil tunnel [J]. Rock and Soil Mechanics, 2021, 42(12): 3451-3466.
[10] XU Hao-chun, JIN Ai-bing, ZHAO Yi-qing, WANG Ben-xin, WEI Li-chang, . Experimental studies on split mechanical properties and fracture evolution behavior of bedding sandstone after high-temperature treatment [J]. Rock and Soil Mechanics, 2021, 42(11): 3069-3078.
[11] ZHAO Jin-shuai, PEI Shu-feng, XU Jin-peng, JIANG Quan, CHEN Bing-rui, . Microseismic evolution of rock mass with staggered zone of underground intersecting chambers under excavation disturbance [J]. Rock and Soil Mechanics, 2020, 41(11): 3789-3796.
[12] SHI Dan-da, MAO Yi-yao, YANG Yong, YUAN Yuan, HAO Dong-xue, . Experimental study on the deformation characteristics of soils around uplift circular plate anchors using digital image correlation technology [J]. Rock and Soil Mechanics, 2020, 41(10): 3201-3213.
[13] LOU Ye, ZHANG Guang-qing. Experimental analysis of fracturing fluid viscosity on cyclic hydraulic fracturing [J]. Rock and Soil Mechanics, 2019, 40(S1): 109-118.
[14] WU Shun-chuan, MA Jun, CHENG Ye, CHENG Zi-qiao, LI Jian-yu, . Review of the flattened Brazilian test and research on the three dimensional crack initiation point [J]. Rock and Soil Mechanics, 2019, 40(4): 1239-1247.
[15] WANG Deng-ke, SUN Liu-tao, WEI Jian-ping, . Microstructure evolution and fracturing mechanism of coal under thermal shock [J]. Rock and Soil Mechanics, 2019, 40(2): 529-538.
Viewed
Full text


Abstract

Cited

  Shared   
  Discussed   
[1] WANG Gang, LI Shu-cai, WANG Ming-bin. Study of stability of anchoring jointed rockmass under seepage pressure[J]. , 2009, 30(9): 2843 -2849 .
[2] JIE Yu-xin, YANG Guang-hua. Modification of elastoplastic models based on generalized potential theory[J]. , 2010, 31(S2): 38 -42 .
[3] YANG Jian-min, ZHENG Gang. Classification of seepage failures and opinion to formula for check bursting instability in dewatering[J]. , 2009, 30(1): 261 -264 .
[4] ZHOU Hua,WANG Guo-jin1,,FU Shao-jun,ZOU Li-chun,CHEN Sheng-hong. Finite element analysis of foundation unloading and relaxation effects of Xiaowan Arch Dam[J]. , 2009, 30(4): 1175 -1180 .
[5] YE Fei, ZHU He-hua, HE Chuan. Back-filled grouts diffusion model and its pressure to segments of shield tunnel[J]. , 2009, 30(5): 1307 -1312 .
[6] LUO Qiang , WANG Zhong-tao , LUAN Mao-tian , YANG Yun-ming , CHEN Pei-zhen. Factors analysis of non-coaxial constitutive model’s application to numerical analysis of foundation bearing capacity[J]. , 2011, 32(S1): 732 -0737 .
[7] WANG Yun-Gang ,ZHANG Guang ,HU Qi. Study of force characteristics of battered pile foundation[J]. , 2011, 32(7): 2184 -2190 .
[8] GONG Wei-ming, HUANG Ting, DAI Guo-liang. Experimental study of key parameters of high piled foundation for offshore wind turbine[J]. , 2011, 32(S2): 115 -121 .
[9] WANG Cheng-bing. Laboratory and numerical investigation on failure process of tunnel constructed in homogeneous rock[J]. , 2012, 33(1): 103 -108 .
[10] SONG Yi-min , JIANG Yao-dong , MA Shao-peng , YANG Xiao-bin , ZHAO Tong-bin . Evolution of deformation fields and energy in whole process of rock failure[J]. , 2012, 33(5): 1352 -1356 .