Coupling control on pillar stress concentration and surface cracks in shallow multi-seam mining

• 作者: Qingxiang Huang Junwu Du Jie Chen Yanpeng He
• 来源期刊: 矿业科学技术学报（英文版）
• 年，卷（期）: 2021,（1）
• 页码范围: 95-101
• 页数: 7页
• 语种: 英文

摘要

In order to ensure safe mining and reduce surface damage in shallow multi-seam mining, the failure char-acteristics of interburden strata with different coal pillars offset distances between pillars in the upper and lower seams, the distribution characteristics of stress concentration in coal pillars, and the develop-ment characteristics of stratum cracks and subsidence were investigated by physical and UDEC2D simu-lation. Meanwhile, the effect of different coal pillar offset distances on stress concentration of coal pillar and development of stratum cracks were studied. Based on those results, a formula for safe mining and reducing surface damage was established, which provided a theoretical basis for safe and environmen-tally friendly mining in shallow multi-seam. According to the results, the optimal coal pillar offset dis-tance (the side to side horizontal distance of the upper and lower coal pillars) between the upper and lower coal seams was developed to reduce the stress concentration of coal pillars and surface damage. The results of this study have been applied in Ningtiaota coal mine and have achieved good results in safe and environmentally friendly mining.