煤炭技术

为掌握松散承压含水层下厚煤层开采覆岩破坏及导水裂隙发育规律，综合运用理论分析、数值模拟和相似模拟试验相结合的研究方法，对顾北煤矿14321上限工作面采用分层开采和综放开采的安全煤柱高度、导水裂隙带发育高度和覆岩垮落形态进行了对比分析。研究结果表明：上分层开采时，应留设的防砂安全煤柱高度25.04 m，小于实际最小基岩厚度38.90 m，裂隙带发育高度为39.00 m，位于基岩面附近，覆岩垮落形态呈梯形，与一般工作面相似；综放开采时，应留设的防砂安全煤柱高度为69.77 m，裂隙带发育高度为106.5 m，已经波及到中部含水层。针对厚煤层俯斜开采上提工作面，设计了从切眼开始先分层开采，待基岩逐渐增厚，采用放顶煤的差异化放煤技术，并在顾北煤矿14321工作面获得了成功应用。

In order to grasp the overlying strata failure and water conducting fracture zone development law of thick coal seam mining under unconsolidated confined aquifer, the research methods including theoretical analysis, numerical simulation and similar simulation experiments were comprehensively applied to compare and analyze the safety coal pillar height, water-conducting fracture zone development height and overlying rock collapse morphology of the 14321 upper exploitation limitationhe ightened working face in Gubei Coal Mine by layered mining and fully mechanized top coal caving mining. The results show that: when using upper layer mining, the sand-prevention safety coal pillar height that should be left is 25.04 m, which is less than the actual minimum bedrock thickness of 38.90 m.The height of the developed fracture zone is 39.00 m, located near the bedrock surface, and the collapse shape of the overlying rock is trapezoidal, similar to that of a general working face. However,when using fully mechanized top coal caving mining, the sand-prevention safety coal pillar height that should be left is 69.77 m, and the height of the developed fracture zone is 106.5 m, which has already affected the central aquifer. A differentiated top coal caving technology was designed for the inclined mining of thick coal seams, which starts with layered mining from the cutting hole and gradually thickens the bedrock before top coal caving. This technology has been successful applied in the 14321 working face of Gubei Coal Mine.