缓倾斜中厚矿体覆盖层补充问题研究

大顶山矿区属于缓倾斜中厚矿体,采用无底柱分段崩落法进行回采,随着回采分段的不断下降,相当部分的覆盖层会损失在矿体下盘,导致在下分段的回采过程中没有足够的覆盖层来保证安全有效回采。根据大顶山矿体特征,从理论上分析了强制崩落法及自然冒落法在大顶山矿区补充覆盖层的应用可行性。研究得出:对于缓倾斜中厚型矿体,采用强制崩落与自然冒落形成覆盖层的方法是可行的,对于强制崩落形成覆盖层,上盘回采进路推进2~3个步距,可以避免矿岩破碎带给立槽带来困难,并为下分段回采提供足够的覆盖层;对于自然冒落形成覆盖层,为了及时有效地发生自然冒落,采取同时退采3条巷道的方式。

Study on overburden layer supplementary for gently inclined medium thick orebody

Dadingshan Mining Area belongs to the gently inclined medium thick orebody using the sublevel caving method. With the decline of mining segment, a considerable part of covering losses in the orebody footwall, which causes the next segment of the working process without enough cover to ensure safe and effective recovery. According to Dadingshan orebody characteristics, the feasibility application of covering is analyzed theoretically by using forced caving and natural caving method. The study results show that gentle inclined medium thick orebody is feasible using forced caving method and nature caving method to form the covering. For covering formed by forced caving, mining entrance of hanging wall should promote 2~3 drawing paces, which can avoid the difficulty of the cut slot brought by ore fracture zone and provide adequate covering to the next sublevel. For covering layer formed by natural caving, in order to make the natural caving occur timely and effectively, retreat mining of 3 tunnels should be adopted.