School of Energy and Mining Engineering, China University of Mining and Technology-Beijing
State Key Laboratory of Water Resource Protection and Utilization in Coal Mining
School of Mining Engineering, Anhui University of Science & Technology, Huainan

为了获得上湾矿特大采高(8.8m)工作面高强度开采的覆岩-地表移动特征,对基岩破断移动、地表下沉开裂以及矿压显现进行了系统观测。观测结果表明:与传统厚硬岩层为主导的高强度覆岩移动特征不同,上湾矿12401工作面采动覆岩移动主要受三层控制层的影响,分别为基本顶、关键层以及顶部厚软岩层(缓冲层),且由于推进速度的影响形成了“两带”和“三带”基岩的破坏模式。下位基本顶和关键层共同决定工作面的矿压显现程度;关键层的破断导致基岩整体剧烈沉降,同时由于缓冲层为厚而软的砂质泥岩,具有较强的膨胀性,对开采覆岩移动传导具有一定的缓冲作用,是基岩形成“三带”的关键因素。通过对覆岩-地表移动规律的分析,提出了基于覆岩控制层的地表裂缝主控机理,获得了推进速度影响下的覆岩-地表移动特征,为预防采动地表破坏和实现减损开采提供了科学依据。

In order to obtain the characteristics of overburden-surface movement of high-intensity mining in the super high mining height (8.8 m) longwall face of Shangwan coal mine, systematic observations were made for overburden breaking and movement, surface subsidence and cracking, and mining- induced pressure behavior. The observation results showed that the migration characteristics of overburden were different from that dominated by traditional thick-hard strata. A three-layer controlling stratum, the main roof, the primary key stratum and the thick-soft rock layer at the top ( buffer stra- tum), influenced the mining movement characteristic of 12401 longwall face, and due to the influence of the advancing speed, an overburden fracture mode consisting of “two zones” or “three zones” wasformed. Low-level main roof and primary key stratum jointly determined the appearance of mining-in- duced pressure of the mining face; The fracture of the primary key stratum incurred the violent settlement of the whole overburden. At the same time, certain buffering effect on the movement transition of the overburden was formed due to the occurrence of the buffering thick-soft sandy mudstone layer and its strong expansibility, which contributed to the key factor of the formation of the “ three zones” structure. This paper outlined the main conducting mechanism of surface fissure development based on the movement law of overburden-surface, which provided a scientific basis for preventing sur- face damage caused by mining and implementing loss-reduction mining based on the analysis of the movement law of overburden-surface.

国家自然科学基金项目(52104155);北京市自然科学基金项目(8212032);中央高校基本科研业务费专项资金项目(2024ZKPYNY01)