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Mechanical Analysis of Weakly Cemented Roof of Gob-side Entry Retaining in Fully-Mechanized Top Coal Caving Mining

  • Qingheng Gu
  • Wenkai RuEmail author
  • Yunliang Tan
  • Jianguo Ning
  • Qiang Xu
Original Paper
  • 43 Downloads

Abstract

To investigate the mine pressure behavior of weakly cemented roof of gob-side entry retaining (GER) in fully-mechanized top coal caving mining, the structural characteristics of lateral immediate roof in 4-1101 working face of Awuzisu Coal Mine were studied by using of numerical simulation, theoretical analysis and in-site measurement. Mechanical model of “equivalent block” composite structure of immediate roof was established, and verified by field test. The results indicate that weakly cemented roof has a large caving range, and it is easy to form the “equivalent block” composite structure in mechanized top caving mining. This structure affects roof breaking, and provide vertical constraint to the roof of GER. It explains the phenomenon that, the roof pressure of GER increases with the advancing of the working face, but the growth rate decreases gradually before the main roof breaking. This research can provide reference to roadside support design and surrounding rock control of GER with weakly cemented roof.

Keywords

Weakly cemented Fully-mechanized top coal caving mining Gob-side entry retaining Immediate roof Equivalent block structure 

Notes

Acknowledgements

The research described in this study was financially supported by National Key R&D Program of China (2018YFC0604703), National Natural Science Foundation of China (Ning J.G. No. 51574154, and Tan Y.L. No. 51874190), and the Tai’shan Scholar Engineering Construction Fund of Shandong Province of China (Tan Y.L. No. ts 201511026).

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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Qingheng Gu
    • 1
    • 2
  • Wenkai Ru
    • 2
    Email author
  • Yunliang Tan
    • 1
    • 2
  • Jianguo Ning
    • 1
    • 2
  • Qiang Xu
    • 2
  1. 1.State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and TechnologyShandong University of Science and TechnologyQingdaoPeople’s Republic of China
  2. 2.School of Mining and Safety EngineeringShandong University of Science and TechnologyQingdaoPeople’s Republic of China

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