煤矿采掘工作面覆岩观测孔施工技术应用——以山西省黄岩汇井田15100采掘工作面为例

以山西省黄岩汇井田15100采掘工作面所施工的两个“三带”观测孔为例,介绍了通过冒落带角、导水裂缝角和导水裂缝带的计算来确定钻孔位置的基本方法。针对覆岩观测孔的施工难点,提出了相应的应对措施,并详细说明了GC-2观测孔施工中出现的各种问题及解决方法。认为钻孔冲洗液法是目前煤矿取得“三带”数据较为精确的方法,根据钻孔冲洗液漏失量的大小及覆岩的开裂情况,对“三带”进行了划分：在钻进中覆岩一般开裂,冲洗液漏失量小于1L/（s·m）为弯曲带;钻进中覆岩严重开裂,冲洗液漏失量大于1.0L/（s·m）为导水裂缝带;钻进中覆岩出现掉钻,冲洗液漏失量大于1.0L/（s·m）为冒落带。

Application of Coalmine Extraction Face Overlying Rock Observation Hole Construction ---To Take the No.15100 Extraction Face of Huangyanhui Minefield,Shanxi Province as Example

To take construction of two ＂3 zones＂ （here and hereafter the ＂3 zones＂ means caving zone, fractured zone and sagging zone） observation holes in the No.15100 extraction face of Huangyanhui minefield, Shanxi Province as example, introduced a basic method to determine borehole location through angle of caving zone, angle of water conducted fracture and water conducted zone computation. Aimed at difficult points in observation hole construction, put forward corresponding countermeasures, and illustrated all sorts of problems come forth in GC-2 observation hole construction and their way out in detail. The authors considered that the borehole flushing fluid method is a rather accurate method to get the ＂3 zones＂ data at present, according to fluid leakage and overlying rock fracturing condition to divide ＂3 zones＂. During the drilling, if overlying rock is fractured in general, fluid leakage less than 1.0L/s·m can be defined as sagging zone; overlying rock seriously disintegrated, fluid leakage 〉1.0L/s·m as water conducted fractured zone; drill tools falling off in capping rock, fluid leakage 〉1.0L/s·m as caving zone.