Feng Du, Xuan Fan, Zhenhua Li, Zhengzheng Cao, Wenqiang Wang, Feifei Lu, Yufei Jiang
School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo, 454000, Henan, China.
Henan Mine Water Disaster Prevention and Control and Water Resources Utilization Engineering Technology Research Center, Henan Polytechnic University, Jiaozuo, 454000, Henan, China.
Sci Rep. 2024 May 20;14(1):11458. doi: 10.1038/s41598-024-62375-7.
In the mining process of the II1 coal seam at Zhaogu No. 2 coal mine, a method of stratified mining is employed, leaving relatively wide coal pillars in sections. To enhance the resource recovery rate, the mine carries out the cooperative mining of the sectional coal pillars and the lower layer coal seam. The 14,022 cooperative working face of fully-mechanized and fully-mechanized top-coal caving at Zhaogu No. 2 coal mine is taken as the research object. Through numerical simulation, theoretical calculations, and on-site industrial trials, a comprehensive analysis of the overburden structural characteristics and the support adaptability at the working face is conducted. It is clarified that a stress arch bearing structure can be formed above the sectional coal pillars during cooperative mining, and this structure is controlled by key strata. The formation of a stress arch bearing structure in the overburden above the sectional coal pillars provides protection for the underlying mining area. A formula for calculating the working resistance of hydraulic supports under the stress arch in sectional coal pillar is derived. Based on these results, the working resistance of hydraulic supports in the coal pillar area is calculated and selected. Field application shows that the working resistance of the support is 10,000 kN in the fully-mechanized top-coal caving working face, and is 9000 kN in fully-mechanized working face, meeting the support requirements and ensuring safe mining at the working face. This study provides a valuable engineering reference for achieving cooperative mining of abandoned sectional coal pillars and lower layer coal seam in stratified mining method.
在赵固二矿二1煤层开采过程中，采用分层开采方法，在区段内留设了较宽的煤柱。为提高资源回收率，该矿开展了区段煤柱与下层煤层的协同开采。以赵固二矿14022综采综放协同工作面为研究对象，通过数值模拟、理论计算和现场工业试验，对工作面覆岩结构特征及支架适应性进行了综合分析。明确了协同开采过程中区段煤柱上方可形成应力拱承载结构，且该结构受关键层控制。区段煤柱上方覆岩中应力拱承载结构的形成，为下部开采区域提供了保护。推导了区段煤柱应力拱下液压支架工作阻力的计算公式。基于这些结果，计算并选取了煤柱区域液压支架的工作阻力。现场应用表明，综放工作面支架工作阻力为10000kN，综采工作面为9000kN，满足支护要求，保证了工作面的安全开采。该研究为实现分层开采方法中废弃区段煤柱与下层煤层的协同开采提供了有价值的工程参考。
