基于组合赋权法的煤层底板突水危险性研究

Study on water inrush risk of coal seam floor based oncombination weighting method

煤矿水害是仅次于瓦斯爆炸的重大灾害,严重威胁着煤矿井下作业人员生命安全,而且也会造成煤矿经济损失严重。渭北煤田复杂水文地质条件,煤层开采时受到底板奥灰含水层水害威胁严重,底板突水危险性分区预测是关系到煤矿安全生产的关键性问题。以西卓煤矿为例,选取隔水层厚度、奥灰含水层水压、底板破坏深度、断层分维值等煤层底板突水主控因素作为评价指标,建立适用西卓煤矿的底板突水危险性评价体系;利用主成分分析法、变异系数法和CRITIC赋权法分别确定权重,运用Lagrange乘子法取得最优组合权重,建立煤层底板突水脆弱性指数评价模型,并通过Surfer结合克里金插值法对研究区突水危险性进行分区,得到西卓煤矿煤层底板突水危险性评价分区图。研究结果表明,井田中部区域相对比较安全,分别向井田南部和北部危险程度依次增大;与突水系数法结果对比,所得到的评价结果更加精确详细,可为矿井底板突水防治提供参考。

Water disaster in coal mine is also a major disaster second only to gas explosion,which seriously threatens the life safety of underground coal mine operators and also causes serious economic losses in coal mine.The complex hydrogeological conditions of Weibei Coalfield make the coal seam seriously threatened by Ordovician limestone aquifer.Therefore,the zoning prediction of floor water inrush risk is a key problem related to the safety of coal mine production.Taking Xizhuo Coal Mine as an example,the main controlling factors of coal seam floor water inrush,such as the thickness of water barrier layer,water pressure of Ordovician limestone aquifer,floor failure depth and fault fractal dimension value,were selected as evaluation indexes,and a floor water inrush risk evaluation system suitable for Xizhuo Coal Mine was established.The weights were determined using principal component analysis,coefficient of variation,and CRITIC weighting methods,and the optimal combination weights were obtained using the Lagrange multiplier method.A vulnerability index evaluation model for water inrush from the coal seam floor was established,and the water inrush risk in the study area was zoned using surfer and Kriging interpolation method.The zoning map for water inrush risk assessment in the coal seam floor of Xizhuo Coal Mine was obtained.The results showed that the central area of the wellfield was relatively safe.The danger level increases sequentially towards the southern and northern parts of the wellfield.Compared with the results of the water inrush coefficient method,the evaluation results obtained are more accurate and detailed,providing reference for the prevention and control of water inrush from the mine floor.