砂垫层-土工织物复合滤层反滤特性试验研究  

Experimental study on filtration characteristics of sand-geotextile composite filter

作　　者：刘胜 王媛 冯迪[2] LIU Sheng;WANG Yuan;FENG Di(College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 210098,China;College of Civil and Transportation Engineering,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学水利水电学院,江苏南京210098 [2]河海大学土木与交通学院,江苏南京210098

出　　处：《华中科技大学学报（自然科学版）》2023年第4期104-111,共8页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(U2240210,52179100);江苏省卓越博士后计划资助项目(2022ZB182);江苏省水利科技项目(2021075)。

摘　　要：为减轻尾矿库中土工织物滤层的物理淤堵,保障尾矿库安全运行,在尾矿砂与土工织物滤层之间设置了一层砂垫层,形成砂垫层-土工织物复合滤层.通过梯度比试验,验证了砂垫层减轻土工织物滤层物理淤堵的效果,分析了砂垫层的粒径对复合滤层反滤性能的影响,揭示了砂垫层-土工织物复合滤层的工作机理.试验结果表明:在土工织物与尾矿砂之间设置合理的砂垫层后,土工织物的淤堵程度降低,砂垫层可有效阻止土工织物表面低渗透性滤饼的形成.复合滤层排水能力明显高于土工织物滤层,随着砂垫层粒径的增大,复合滤层的流量逐渐增大并趋于稳定.为使复合滤层同时具有良好的保土能力、透水能力和长期抗淤堵能力,建议砂垫层特征粒径D_(15)与尾矿砂特征粒径d_(85)的比值为10左右.To reduce the physical clogging of geotextile filter in tailings pond and ensure the safe operation of tailings pond,a sand filter was placed between tailings sand and geotextile filter to form sand-geotextile composite filter.Through the gradient ratio test,the effect of sand filter to reduce the physical clogging of geotextile filter was verified,the influence of the particle size of sand filter on the filtration performance of composite filter was analyzed,and the working mechanism of sand-geotextile composite filter was revealed.Test results show that the reasonable sand filter between the geotextile and the tailings decreases the clogging degree of the geotextile,and the sand filter effectively prevents the formation of low permeability filter cake at the surface of the geotextile.The drainage capacity of the composite filter is obviously higher than that of the geotextile filter.With the increase of the particle size of the sand filter,the flow of the composite filter gradually increases and tends to be stable.To make the composite filter have good soil retention capacity,good permeability and long-term anti clogging capacity,it is suggested that the ratio of the characteristic particle size D_(15) of sand filter to the characteristic particle size d_(85) of tailing sand should be about 10.

关 键 词：砂垫层 土工织物 复合滤层 反滤特性 尾矿库 

分 类 号：TU4[建筑科学—土工工程]