ABSTRACT
This paper investigated the effects of gas pressure, in-situ stress, and coal strength on coal and gas outbursts (CGO) based on the laboratory CGO experimental data. Based on the hypothesis of the comprehensive of CGO, the single-factor control variable method was used to analyze and evaluate the relative outburst intensity, the characteristics of outburst holes, the distribution of pulverized coal, the drops of outburst gas pressure, and the pulverized coal density under different outbursts experimental condition. The improved CGO energy equation and instability criterion are proposed as a direction to study the occurrence of CGO as an energy evolution direction. Furthermore, the results shows that the initial outburst gas pressure was 0.45 MPa during the experimental conditions of in-situ stress was 5 MPa, and the coal strength was 0.24 MPa. The gas pressure is directly proportional to the relative outburst intensity, while the in-situ stress and coal strength are inversely proportional to the relative outburst intensity. After the CGO occurred, the outburst coal always show spallation and pulverization characteristics. The results highlight that the gas pressure plays a key role in pulverizing and throwing out the pulverized coal, and the in-situ stress mainly plays a role in destroying the coal, and the coal strength plays a resistance role during the CGO occurs. It is also found that pulverized coal particles size less than 0.28 mm can be used to represent the distribution pattern of the total weight of outburst pulverized coal particles in the different outburst interval. These results clearly illustrate that using effective methods to control gas pressure, in-situ stress, and coal strength has an important role in preventing and controlling CGO on coal mining sites.
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Han Meng
Han Meng is a lecturer at the school of Mining and Geomatics Engineering, Hebei University of Engineering, Handan, China. His research focuses on mine coal and gas outbursts disaster prevention and control.
Yuzhong Yang
Yuzhong Yang is a professor at the school of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo, China. His research focuses on mine gas disaster prevention and control.
Haijun Guo
Haijun Guo is a associate professor at the School of Emergency Management and Safety Engineering, China University of Mining and Technology, Beijing, China. His research focuses on mine coal and gas disaster prevention and control.
Wei Hou
Wei Hou is a professor at the school of Mining and Geomatics Engineering, Hebei University of Engineering, Handan, China. His research focuses on mine safety, emergency management.
Xinwang Li
Xinwang Li is a professor at the school of Mining and Geomatics Engineering, Hebei University of Engineering, Handan, China. His research focuses on mine safety, coal mining methods and techniques.
Li Chen
Li Chen is a associate professor at the school of Mining and Geomatics Engineering, Hebei University of Engineering, Handan, China. His research focuses on mine safety. Tenglong Rong
Tenglong Rong
Tenglong Rong is a lecturer at the school of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo, China. His research focuses on multi-field coupled gas seepage in deep coal mines.
Fenghua An
Fenghua An is a associate professor at College of Safety Science and Engineering, Henan Polytechnic University, Jiaozuo, China. His research focuses on coal mine gas control.
Daming Yang
Daiming Yang is a lecturer at the school of Mining and Geomatics Engineering, Hebei University of Engineering, Handan, China. His research focuses on mine pressure and formation control.