厚松散含水层下重复采动覆岩破坏规律分析

Failure overburden law analysis of the repeated mining under the thick unconsolidated aquifers

在厚松散含水层下采煤时,由于含水层可传递上覆表土层的载荷,导致工作面容易产生溃砂、突水事故.为了避免在回采过程中发生溃砂、突水事故,结合朱仙庄煤矿864工作面的实际条件,建立复合隔水关键层的力学模型,采用数值模拟对厚松散含水层下特厚煤层分别在上分层2.5,3.0,3.5,4.O m综采、下分层6.5,6.O,5.5,5.0 m综放和一次性全厚放顶煤进行开采,确定安全开采的方案.研究结果表明:在上分层为3 m下分层6综放时,裂缝带发育的高度最低、覆岩破坏的最终形态最缓和,在工作面回采过程中最为安全.

Because of the load of the overlying alluvium can be passed by inrush accident happens easily on burst face when people are mining under thick aquifers, collapse of sand and water and unconsolidated aquifers. In order to avoid collapse of sand and water inrush accident occurred in the mining process, the project should combine the actual conditions of 864 in Zhuxianzhuang coal mine working face and establish mechanical models of composite riser critical layer. The numerical simulation for thick coal seam under thick and unconsolidated aquifer respectively is 2.5,3.0, 3.5,4.0 m mechanized mining in the up stratified, 6.5,6.0,5.5,5.0 m fully mechanized caving under the hierarchical and one - time full - thickness caving exploitation. The safety of mining programmes must be determined. Research results show that the situation of minimum crack development height, the most ease eventually forms on overburden failure and the safest about mine working face will appear when the numerical simulation is 3.0 m mechanized mining in the up stratified. 6.0 m fully mechanized caving under the hierarchical.