Geomechanics and Engineering

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Study on damage law and width optimization design of coal pillar with the discrete element method

  • Chuanwei Zang (College of Energy and Mining Engineering, Shandong University of Science and Technology) ;
  • Bingzheng Jiang (College of Energy and Mining Engineering, Shandong University of Science and Technology) ;
  • Xiaoshan Wang (School of Science, Qingdao University of Technology) ;
  • Hao Wang (College of Energy and Mining Engineering, Shandong University of Science and Technology) ;
  • Jia Zhou (College of Energy and Mining Engineering, Shandong University of Science and Technology) ;
  • Miao Chen (College of Energy and Mining Engineering, Shandong University of Science and Technology) ;
  • Yu Cong (School of Science, Qingdao University of Technology)
  • Received : 2022.09.14
  • Accepted : 2024.05.14
  • Published : 2024.06.25
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Abstract

The reasonable setting of coal pillar width plays a key role in guaranteeing the steadiness of surrounding rock of fully mechanized caving gateroad driving along the next goaf. Based on the engineering background of the Bayangaole mine, the discrete element method was used to simulate the fracture evolution of coal pillars with different pillar widths. The results show that the damage rate of the coal pillar increases with the decrease in the width of the coal pillar. Once the coal pillar width is smaller than 6 m, cracks run through the coal pillar, and the coal pillar is completely damaged. In the middle of the coal pillar, which has a width of 6 m and above, there is a relatively complete area with low damage. The results show that the pillar width of 6 m is the most appropriate. Field tests prove that the reserved width of a 6 m small coal pillar can effectively control the surrounding rock deformation, ensuring the overall steadiness of the gateroad in the thick coal seam. It is hoped that this study will offer some reference for the determination of the reasonable size of the coal pillar.

Keywords

Acknowledgement

The research was supported by the National Natural Science Foundation of China (52374128, 42207201, 52004145) and the Natural Science Foundation of Shandong Province(ZR2020QE119).

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