煤矿涌水量预测和疏降流场数值模拟研究

Prediction of coal mine water inflow and numerical simulationstudy of dredging flow field

为了安全开采深部煤炭资源,预防煤层底板岩溶水突水事故,必须将灰岩水位降低至安全高度。采用均衡法计算和评价矿区岩溶水多年的补给量和排泄量,求得多年平均补给量为3 690 m^(3)/h,排泄超过补给,岩溶水处在负均衡状态。采用非稳定流解析法和相关分析法,预测了煤矿涌水量,疏放降深S=100 m时,正常涌水量Q正常=4 036 m^(3)/h,最大涌水量Qmax=5 247 m^(3)/h;疏放降深S=220 m时,正常涌水量Q正常=7 637 m^(3)/h,最大涌水量Qmax=9 928 m^(3)/h;对矿区岩溶水疏降流场进行数值模拟得出,由于疏水井不断排泄,寒武系灰岩承压含水层水位快速下降,形成明显的降落漏斗,这主要与疏水井设计在富水区内、渗透系数及外界补给量有关,预测了寒武系灰岩含水层疏水水位等值线。

In order to safely mine deep coal resources and prevent karst water inrush accidents from the coal seam floor,the limestone water level must be lowered to a safe height.The equilibrium method is used to calculate and evaluate the multi-year karst water supply and discharge in the mining area,and the average multi-year supply is 3690 m^(3)/h,the discharge exceeds the replenishment,and the karst water is in a negative equilibrium state;the unsteady flow analysis method and the relevant analysis method are used to calculate the prediction of the coal mine water inflow,and it is concluded that when the dredging depth S=100 m,the normal water inflow Q normal=4036 m^(3)/h,the maximum water inflow Q max=5247 m^(3)/h;when the evacuation depth S=220 m,the normal water inflow Q normal=7637 m^(3)/h,the maximum water inflow Q max=9928 m^(3)/h;numerical simulation of the drainage flow field of karst water in the mining area shows that due to the continuous discharge of drainage wells,the water level of the Cambrian limestone confined aquifer rapidly decreases,forming a clear depression funnel.This is mainly related to the design of drainage wells in the rich water area,permeability coefficient,and external supply.The drainage water level contour of the Cambrian limestone aquifer is predicted.