多关键层厚硬顶板覆岩破断运动规律研究

Breaking and moving laws of overburden of multi-key layer thick hard roof

针对榆神矿区多层厚硬顶板条件下工作面“大、小周期来压”现象及矿压显现强烈问题,综合采用理论分析、数值计算以及微震实测等手段,对曹家滩矿多层厚硬顶板条件下工作面顶板破断运动及工作面来压规律进行分析研究。结果表明:垂高40m范围内的低位基本顶及关键层是影响工作面“小周期”来压的主要顶板层位;垂高70~150 m范围内的中高位关键层破断具有“低频次”“大断距”的特点,并与“大周期”存在密切关联;高低层关键层破断的时空叠加是工作面发生“大周期来压”的重要致因。研究结论对深化榆神矿区类似地质条件下工作面“大周期”强矿压现象的理解以及指导后续系统治理工程实践的开展具有积极指导意义。

In view of the phenomenon of“large and small periodic weighting”of the working face under multi-layer thick and hard roof in Yushen mining area and the strong mine pressure behavior,theoretical analysis,numerical calculation and microseismic measurement were used to study the roof breaking movement and the law of working face weighting under multilayer thick and hard roof.The results show that the low basic roof and the key layer within the vertical height of 40 m are the main roof layers that affect the small periodic weighting;the fracture of medium and high level key layers within the vertical height range of 70~150 m has the characteristics of“low frequency”and“large breaking interval”,and is closely related to the large period weighting;the time-space superposition of the key layer breaking of the high and low layers is an important cause of the large period weighting in the working face.The research conclusion can offer reference for deepening the understanding of the large period strong mine pressure behavior in the working face under similar geological conditions in Yushen mining area and guiding the subsequent systematic control engineering practice.