济南承压含水层场地单井常压回灌试验研究

Experimental study on the single well natural recharge in the confined aquifer of Jinan area

单井常压回灌特性作为地下水回灌的一项基础研究内容,对其研究的成果将为基坑降水回灌及地下水资源保护提供有力的技术支持。文章针对济南典型多层承压含水层的非均质场地,通过不同的回灌布置方式,进行单井回灌的常规和精细试验,获取真实场地条件下回灌井内动水位水头差、日回灌量、观测井水位变化等试验数据,并分析单井常压回灌能力和影响范围的理论与试验结果。结果表明:承压含水层单井回灌量与井内稳定水头差呈线性上升趋势,同时当回灌量增大到一定程度,井内稳定水头差增长趋缓,实际与理论计算的水头差差距增大;同场地条件下单井常压回灌量约为抽水量的30%~50%,常压回灌效率较低;实际回灌影响半径远小于理论计算值。

As a basic research contents of groundwater recharge,single-well atmospheric pressure injection characteristics research results will provide strong technical support for the foundation pit precipitation recharge and groundwater resources protection.Jinan typical multilayer heterogeneity site of confined aquifer are selected for conventional and fine experiment of single well injection by different arrangement.Experimental data of dynamic water level,injection quantity and water level changes of observation wells on real site conditions are obtained,and recharge ability and influence range of theoretical and experimental analysis is made.The results show that the recharge rate of confined aquifer in a single well shows a linear upward trend with the steady head difference in the well.When the recharge rate increases to a certain extent,the steady head difference in the well increases slowly,and the gap between the actual head difference and the theoretical head difference increases.Under the same site condition,the atmospheric pressure recharge in a single well is about 30%~50%of the pumping water,and the atmospheric pressure recharge efficiency is low.The effect radius of actual recharge is much smaller than the theoretical calculation.