顶板含水层防水试验的钻孔单位涌水量计算方法

为了实现利用井下放水试验获取顶板含水层的钻孔单位涌水量，采用抽水试验中的地下水动力学计算公式，结合观测孔的水位降深，给出了放水孔水位降深的计算方法；利用观测孔水位降深和观测孔与放水孔之间距离的对数曲线图，提出了放水孔水位降深的图解法；对于承压含水层，基于钻孔单位涌水量与含水层渗透系数之间的线性相关关系，可以通过含水层的渗透系数获取钻孔单位涌水量；通过实例分析，解析法和图解法计算得到的放水孔单位涌水量相近，结合现场放水试验情况，分析了放水孔单位涌水量的可靠性，并对3种方法的适用条件进行了讨论。研究结果表明:利用放水试验获取的放水孔单位涌水量符合实际情况，可以作为含水层富水性评价和矿井水文地质条件分析的依据。

Calculation method of borehole specific capacity based on dewatering tests of roof aquifer

In order to obtain the borehole specific capacity of roof aquifer by using the underground water dewatering tests, combined with the drawdown of observation borehole, a calculation method for the drawdown of dewatering borehole was presented by using the groundwater dynamic calculation formula in the pumping tests. A graphical method for the drawdown of dewatering borehole was put forward by using the logarithmic curve chart of the drawdown of observation borehole and the distance between observation borehole and dewatering broehole. For the confined aquifer, the borehole specific capacity was obtained through the permeability coefficient of aquifer based on the linear correlation between the borehole specific capacity and the permeability coefficient of aquifer. Through a case study, the specific capacity of dewatering borehole obtained by the analytical method was close to that by the graphical method, then the reliability of spedific capacity of dewatering borehole was analyzed by combining with the situation of on site dewatering tests, and the application conditions of three methods were discussed. The results showed that the specific capacity of dewatering borehole obtained by the dewatering tests was in line with the actual situation, which can be used as the basis for the water abundance evaluation of aquifer and analysis of mine hydrogeological conditions.