Scale effect stress–strain model of coal containing gas

  • Cuijun Jin
  • Songyong LiuEmail author
  • Panpan Xu
  • Chuwen Guo
Technical Paper


This paper reviews the relationship between mechanical properties and scale effect of coal specimens containing gas in stress condition. Firstly, the scale effect stress–strain model of coal was established based on Weibull theory and modified Terzaghi equation. And then, the scale effect stress–strain model of coal containing gas was proposed considering the effect of interfacial friction and expansion force of gas. Lative parameters of the model were obtained through experiments. The mechanical properties of coal specimens containing gas were analyzed, and the correctness of the theoretical model was validated. The results indicate that the theoretical curve of the coal specimens’ compressive strength varying with height–diameter ratio shows consistency with experimental curve. The theoretical scale effect stress–strain curve of coal containing gas agrees well with the experiment at the pre-peak. With the increase in the height–diameter ratio, the coal specimens’ compressive strength decreases and the elastic modulus increases. The coal specimens’ compressive strength and elastic modulus decrease with the gas pressure.


Coal Weibull theory Gas pressure Scale effect Interfacial friction 



This work was supported by the National Natural Science Foundation of China (No. U1510113), the Top-notch Academic Programs Project of Jiangsu Higher Education Institutions (TAPP), and Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).


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Copyright information

© The Brazilian Society of Mechanical Sciences and Engineering 2019

Authors and Affiliations

  • Cuijun Jin
    • 1
    • 2
  • Songyong Liu
    • 1
    • 2
    Email author
  • Panpan Xu
    • 1
    • 2
  • Chuwen Guo
    • 1
    • 3
  1. 1.School of Mechatronic EngineeringChina University of Mining and TechnologyXuzhouChina
  2. 2.Jiangsu Collaborative Innovation Center of Intelligent Mining EquipmentChina University of Mining and TechnologyXuzhouChina
  3. 3.School of Electric Power EngineeringChina University of Mining and TechnologyXuzhouChina

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