综采工作面覆岩导水裂隙带高度研究

Study on the height of water-conducting fracture zone in overburden rock of fully mechanized mining face

整个范各庄井田均为第四系冲积层所覆盖,其中底砾层是煤系地层上部的重要承压含水层。在开采浅部煤层时,由于该含水层富水性强,为了确保回采过程中不受上覆含水层的影响,必须研究确定覆岩导水裂隙带高度,合理留设防水安全煤岩柱。以范各庄矿3553S综采工作面为例,采用经验公式法预计导水裂隙带高度,然后通过井下钻探手段实测,最后综合判断覆岩导水裂隙带的发育高度。结果表明,经验公式法预计的导水裂隙带高度与现场实测结果基本吻合,综合两者结果,确定该工作面采后的导水裂隙带最大高度为37.23 m。

The entire Fangezhuang minefield is covered by the Quaternary alluvium,and the bottom gravel layer is an important confined aquifer in the upper part of the coal-bearing strata.When the shallow coal seam was mined,because of the rich aquifer,in order to ensure that it was not affected by the overburden during the mining process,it was necessary to study the height of the overburden fracture zone and reasonably leave a waterproof and safe coal pillar.The 3553S fully mechanized mining face of Fangezhuang Mine was taken as an example,the height of the water-conducting fracture zone was predicted by the empirical formula method,and then measured by downhole drilling method.Finally,the development height of the fractured water-conducting fracture zone was comprehensively judged.The results showed that the height of the water-conducting fracture zone predicted by the empirical formula method basically consistent with the field test results.The combined results showed that the maximum height of the water-conducting fracture zone after the mining face was 37.23 m.