In the process of reinjection of groundwater,the aquifer clogging is the key problem restricting the ef-ficiency of artificial groundwater recharge.Precipitation of suspended solids is the most important fact of aquifer clogging.This article experimentally studied the suspended solid clogging processes,systematically investigated the clogging depth and clogging rates by injecting water with suspended particles into three typical aquifer media of Li -yuan reinjection testing site(in Gaocheng district of Shijiazhuang city).The results showed that the permeability coefficient reduced in the upper layer at the beginning of the experiment once the clogging occurred;the permeabil-ity first increased and then decreased in the inner layer along the time.The most serious clogging occurred closes to the surface and the clogging depth had positive correlation with the particle size of the media.Within the influence depth of clogging, the degree of permeability declining is continuously reduced over time.The surface clogging rates varied from 0.91/h for coarse sands,to 0.66/h for fine sand,and down to 0.58/h for medium sand.clogging rates is negatively correlated with the permeability coefficient of the corresponding layer when the interior media is clogged.%地下水人工回灌过程中含水层堵塞问题是制约地下水回灌效率的关键因素,引起含水层堵塞现象中最主要的类型为悬浮物堵塞.通过室内实验的方法,根据石家庄市藁城区梨园人工回灌场地的垂向介质特征,选取3种不同的典型含水介质作为入渗介质,将悬浊水连续注入3种介质中,刻画悬浮物堵塞在场地介质中的发展规律,量化堵塞深度及堵塞速率.实验结果表明:回灌时介质表层的渗透系数随时间逐渐减小,逐渐向介质内部发展时渗透系数随时间先增大后减小.实验介质均在靠近表层的部位发生严重堵塞,堵塞深度与介质粒径大小呈正相关,且在堵塞影响深度范围内,随时间的延长,介质渗透系数降幅不断减小.粗砂比重大的介质表层堵塞速率为0.91/h,细砂比重大的介质表层堵塞速率为0.66/h,中砂比重大的介质表层堵塞速率为0.58/h.介质内部发生堵塞时堵塞速率与相应层位介质的渗透系数呈负相关.
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