深部矿井水害特征、评价方法与治水勘探方向

煤矿区深部含水层具有大埋深、高水压等特点,是深部煤层开采水害防范的主要对象。在分析深部矿井水害特征基础上,探讨了深部矿井地应力对裂隙水介质的力学作用机制,阐述了深部矿井裂隙水介质呈现"高承压、弱富水"的力学原因;基于古岩溶成因演化理论,结合水文地质勘探和野外调查,分析探讨了华北型煤田奥陶纪石灰岩顶部"古风化壳"的岩溶充填结构特征,并将奥陶纪石灰岩顶部"古风化壳"划分为"隔水充填带、弱隔(透)水充填带、富(透)水带"3种岩溶充填结构类型,给出了各类型确定的关键指标和阈值,明确了奥陶纪灰岩顶部存在隔水层的理论依据。将深部矿井煤层开采底板突水划分为"完整底板突水模式"和"集中破碎带底板突水模式",分析了深部煤层开采底板含水层高水压作用下沿用传统的突水系数法(T_s法)评价底板突水危险性的局限性,引入隔水层厚度(M)和含水层钻孔单位涌水量(q)2个指标,结合突水实例分析,提出了"修正的突水系数法"(T_s-M-q法,适用于完整底板突水模式);在实验和实例分析基础上,提出"渗-流转换"突水评价法(适用于集中破碎带底板突水模式)。最后,基于深部矿井水害特征及突水模式,结合深部含水介质赋存、构造发育特征和地应力场方向,阐述了深部矿井水害精准查治一体化勘探关键技术。

Characteristics of water disaster,evaluation methods and exploration direction for controlling groundwater in deep mining

The water source of deep mine water inrush mainly comes from two kinds of water bearing medium:fissure water medium and karst water medium.Based on the mechanical effect of the deep mine stress on the fractured rock mass,it reveals that the fractured water medium in the deep mine exhibits the characteristics of “high confined and weak water yield property”.Based on the evolutionary theory of paleo karst genesis,the karst filling structure of the “archaic crust” on the top of the Ordovician limestone in the North China coalfield is analyzed.The water proof filling belt,the weak water proof filling belt (weak water permeable belt) and the water rich belt (water permeable belt) were divided.With three types of karst filling structures,key indicators and thresholds for type determination were obtained.The water inrush from the mining floor of deep coal seam is condensed into “complete floor water inrush mode” and “concentration fracture zone floor water inrush mode”.The water inrush coefficient method (Ts method) under deep high water pressure is relatively limited.This paper proposed a “corrected water inrush coefficient method” (Ts M q method,suitable for complete floor water inrush mode) and a “infiltrating seepage conversion” water inrush evaluation method (applicable to concentrated fractured zone floor water inrush mode).Based on the characteristics of groundwater in the deep mine and the water inrush mode,the key technology for the integrated exploration of deep mine water damage was described for the purpose of groundwater management.