Influence of Mining Speed on Stope Energy in Deep Mines
Zhi-gang Deng*, Shang Wang, Yun-long MO, Wei-jian Liu
1. Chinese Institute of Coal Science, Beijing 100013, China;
2. China Coal Research Institute, Beijing 100013, China;
3. State Key Laboratory of Coal Mine Disaster Prevention and Control, Beijing 100013, China;
4. Zhongyuan University of Technology, Zhengzhou 450007, China)
Abstract：
Enhancing the mining speed of a working face has become the primary approach to achieve high production and efficiency in coal mines, thereby further improving the production capacity. However, the problem of rock bursts resulting from this approach has become increasingly serious. Therefore, to implement coal mine safety and efficient extraction, the impact of deformation pressure caused by different mining speeds should be considered, and a reasonable mining speed of the working face should be determined. The influence of mining speed on overlying rock breaking in the stope is analyzed by establishing a key layer block rotation and subsidence model. Results show that with the increasing mining speed, the compression amount of gangue in the goaf decreases, and the rotation and subsidence amount of rock block B above goaf decreases, forcing the rotation and subsidence amount of rock block A above roadway to increase. Consequently, the contact mode between rock block A and rock block B changes from line contact to point contact, and the horizontal thrust and shear force between blocks increase. The increase in rotation and subsidence of rock block A intensifies the compression degree of coal and rock mass below the key layer, thereby increasing the stress concentration degree of coal and rock mass as well as the total energy accumulation. In addition, due to the insufficient compression of gangue in the goaf, the bending and subsidence space of the far-fi eld key layer are limited, the length of the suspended roof increases, and the influence range of mining stress and the energy accumulation range expand. Numerical test results and underground microseismic monitoring results verify the correlation between mining speed and stope energy, and high-energy events generally appear 1–2 d after the change in mining speed. On this basis, the statistical principle confirms that the maximum mining speed of the working face at 6 m/d is reasonable.
基金资助:This work was supported by Technology Innovation Fund of China Coal Research Institute (2022CX-I-04), Science and
Technology Innovation Venture Capital Project of China Coal Technology Engineering Group (2020-2-TD-CXY005)
通讯作者: Deng Zhigang (Email: dengzhigang2004@163.com).
E-mail: dengzhigang2004@163.com
作者简介: Deng Zhigang (1981-), Male,Changchun City, Jilin Province, researcher, PhD. His research interests include the prevention and control of rock bursts. TEL: 010-84263796
2025, Vol. 22 
