巨厚煤层开采覆岩含水层破坏模拟——以准东大井矿区为例

本文针对准东矿区巨厚煤层典型赋存特征,以大井矿区为研究对象,通过识别覆岩关键层及含水层,采用UDEC数值模拟方法,建立大井矿区巨厚煤层开采覆岩力学模型,对不同开采方法覆岩含水层破坏进行了模拟研究。结果表明:研究区覆岩关键层分为4层、覆岩含水层共2层;开采厚度相同时,大采高开采覆岩下沉量、裂隙带发育高度及开采对含水层的扰动影响均大于放顶煤开采;采高24m,推进长度为300m时,导水裂隙已发育至含水层Ⅱ;主关键层对覆岩位移、裂隙分布及开采对含水层的扰动影响起关键作用。

Simulation of the impact of super-thick coal seam mining on overlying aquifers: a case study of Dajing mining area of Eastern Junggar Coalfield

With the application of UDEC numerical tool, the authors studied the impact of the super-thick coal seam mining activities on aquifers in Dajing mining area of Eastern Junggar coalfield which is based on the characteristics of coal seam deposition. Results showed that there exist four key strata layers and two aquifers in this mining area. And it also showed that the more of the subdivision of coal seam, the more of the subsidence and the height of fracture of overlying strata, and consequently the higher of the fracturing height of rocks happened for same coal mining thickness which caused much damage to aquifers. On condition of mining 24m height and advancing 300m, the key strata and aquifer No.2 were damaged and collapsed.And the main key strata plays a vital role in the movement of overlying rocks and damage to aquifers.