Dynamic characteristics and crack propagation characteristics of gas-bearing coal under cyclic impact

被引：0
|
作者：
Wang L. [1 ]
Wang A. [1 ]
Chen L. [1 ]
Li S. [1 ]
Liu H. [2 ]
机构：
[1] State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mine, Anhui University of Science and Technology, Anhui, Huainan
[2] School of Energy and Mining Engineering, China University of Mining and Technology(Beijing), Beijing
来源：
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | 2023年 / 42卷 / 11期
关键词：
crack propagation; CT scan; cyclic impact; dynamic characteristics; gas-bearing coal; mining engineering;
D O I：
10.13722/j.cnki.jrme.2023.0165
中图分类号：
学科分类号：
摘要：
In order to explore the cyclic impact dynamic characteristics and crack propagation law of coal under different initial gas pressures，the cyclic impact test of coal under different initial gas pressures is carried out by using the combined dynamic and dynamic loading test system of coal-rock containing gas，and the dynamic stress-strain curve of gas-bearing coal under cyclic impact load is obtained. The relationship between coal dynamic parameters and initial gas pressure under cyclic impact is analyzed ， 3D visualization and fine quantitative characterization of crack propagation process before and after cyclic impact of gas-bearing coal are realized by CT scanning technology. The results show that：(1) the dynamic stress-strain curves of gas-bearing coal under cyclic impact load are basically similar，which are divided into three stages：linear elastic stage，plastic stage and unloading stage. The dynamic parameters of coal under impact load decrease with the increase of the initial gas pressure，and the greater the initial gas pressure，the stronger the gas weakening erosion effect. (2) Based on the fracture slices extracted by CT scanning and the reconstructed 3D fracture results，it is shown that annular parallel cracks and axial splitting through cracks exist in the impinged coal. The crack propagation process can be effectively and quantitatively characterized by two-dimensional and three-dimensional fracture characteristic parameters of gas-bearing coal，and the characteristic parameters are proportional to the initial gas pressure. Under high gas pressure environment，the fracture network in coal body is more complex，the connectivity is higher，and the instability failure is more likely to occur. (3) Based on theoretical analysis，the causes of strength damage and deterioration of coal body are revealed from the perspective of gas erosion and internal stress wave propagation of coal body. Combined with the damage effect of gas and dynamic load on coal body，the causes of strapping failure of cyclic impact coal body under the action of gas are discussed. The research results are helpful to enrich the dynamic theory of gas-bearing coal and have a certain theoretical reference significance for the prevention and warning of coal and gas outburst disaster in mine. © 2023 Academia Sinica. All rights reserved.
引用
收藏
页码：2628 / 2642
页数：14
相关论文
共 55 条
  • [1] XIE Heping, Research review of the state key research development program of China：Deep rock mechanics and mining theory[J], Journal of China Coal Society, 44, 5, pp. 1283-1305, (2019)
  • [2] XIE Heping, Feng GAO, Yang JU, Research and development of rock mechanics in deep ground engineering[J], Chinese Journal of Rock Mechanics and Engineering, 34, 11, pp. 2161-2178, (2015)
  • [3] LI Tie, CAI Meifeng, WANG Jin'an, Et al., Discussion on relativity between rock burst and ga in deep exploitation[J], Journal of China Coal Society, 30, 5, pp. 20-25, (2005)
  • [4] YUAN Liang, Key technique of safe mining in low permeability and methane-rich seam group[J], Chinese Journal of Rock Mechanics and Engineering, 27, 7, pp. 1370-1379, (2008)
  • [5] WANG L, WANG H, ZHU J T, Et al., Experimental study on particle size distribution of impact crushed coal containing gas[J], Fuel, 325, (2022)
  • [6] YUAN Liang, Strategic thinking of simultaneous exploitation of coal and gas in deep mining[J], Journal of China Coal Society, 41, 1, pp. 1-6, (2016)
  • [7] JIN Jiefang, LI Xibing, CHANG Junran, Et al., Stress-strain curve and stress wave characteristics of rock subjected to cyclic impact loadings[J], Explosion and Shock Waves, 33, 6, pp. 613-619, (2013)
  • [8] DAI Bing, LUO Xinyao, SHAN Qiwei, Et al., Analysis on damage characteristics and energy dissipation of rock with a single hole under cyclic impact loads[J], China Safety Science Journal, 30, 7, pp. 69-77, (2020)
  • [9] ZHAO Hongbao, LIU Yihong, LIU Rui, Et al., Influence of dynamic disturbance on coal-rock damage under local static load constraints[J], Journal of Harbin Institute of Technology, 54, 8, pp. 80-89, (2022)
  • [10] KONG Xiangguo, YANG Songrui, WANG Enyuan, Et al., Fracture evolution and gas emission characteristics of raw coal samples subjected to instantaneous disturbance of impact load[J], Chinese Journal of Rock Mechanics and Engineering, 42, 6, pp. 1384-1394, (2023)
123456