“大井法”中渗透系数及含水层厚度的优化

Optimization of permeability coefficient and aquifer thickness in large-well-method

"大井法"是矿井涌水量预测的常用方法之一,但预测误差较大,分析误差原因,主要是含水层厚度与渗透系数不能完全反映实际情况,且取值人为影响较大。通过区域构造复杂程度与抽水试验所得渗透系数的统计分析,发现构造复杂程度与渗透系数呈正相关关系,运用分形理论,对"大井法"的渗透系数取值进行了优化,使其更贴近实际;针对采动破坏沟通顶底板不同含水层导致涌水量变化,提出含水层厚度采用累计加权厚度以及分层涌水量叠加。经过参数优化,避免了其取值时的随意性,范各庄2190工作面涌水量预测结果表明,改进的"大井法"精度大幅提高。

The large-well-method is one of the common methods in the prediction of mine water inflow, but sometimes the errors occur in the prediction, the mainly reason is that the aquifer thickness and the permeability coefficient can't reflect the actual situation and the man-made influence is big. Through statistical analysis of the regional structural complexity and the permeability coefficient obtained from pumping test, the positive relationship was found between the structural complexity and permeability coefficient, by using the fractal theory, the value of permeability coefficient is optimized for large-well-method to be closer to the real situation. Aiming at the changes of water inflow in different aquifers above the roof and below the floor influenced by mining disturbance, the aquifer thickness was weighted cumulatively, the water inflow was the sum of different aquifers. After parameter optimization, the arbitrariness of the parameters selection was avoided, applying the improved large-well-method at working face 2190 in Fangezhuang coal mine, the precision of prediction has been greatly improved.