湖下深部开采下组煤底板突水危险性分区分级预测

Classification and prediction of water inrush risk from coal seam floor with deep coal seam mining under lake

为合理评价滨湖煤矿161西采区16煤底板奥灰突水危险性,在分析采区地质及水文地质特征的基础上,利用突水指数法,选取奥灰含水层的水压、断层密度、断层交点和端点的分布、断层规模指数、底板有效隔水层厚度5个因素作为煤层底板突水预测的主控因素,并制作专题图和均一化图,建立了突水指数评价模型,并进行了危险程度分级分区预测。研究结果表明:按照突水指数n>0.56、0.56≥n>0.43、0.43≥n>0.35、0.35≥n>0.23、n≤0.23,将煤层底板奥灰突水危险等级分别划分为极危险区、危险区、较危险区、较安全区和安全区,评价结果与突水指数法结果相比预测结果更加详细准确,也与实际较为吻合,有助于指导滨湖煤矿161西采区防治水工作。

To evaluate the risk of water inrush from Ordovieian confined aquifer in the western No. 161 mining area of Binhu Coal Mine, based on the analysis of the geologic and hydrogeological characteristics of the mining area, five factors were selected as the main control factors of water inrush prediction of coal seam floor, including the water pressure of the Ordovieian aquifers, fault density, the distribution of fault intersections and end points, fault seale index, effective water impermeable floor thickness, the thematie map and the homogenization map were made, and an evaluation model of water inrush index was established, the risk levels were predicted by regions and levels respectively.Results showed that, according to the value region of water inrush index n〉0.56、0.56≥n〉0.43、0.43≥n〉0.35、0.35≥n〉0.23、n≤0.23,the risk level of Ordovieian limestone water inrush was divided into extreme danger area, dangerous area, dangerous area with some risks ,dangerous area with little risks and safe area.It was proved that the predietion results were in accord with reality, and the evaluation results were similar to the water inrush coefficient, were more detailed and more consistent with the actual situation.The results of classifieation could help to guide the prevention and control of water hazard during mining.