宁夏银北灌区排水暗管土工布外包料透水与防淤堵性能  

Permeability and anti-clogging performance of geotextile envelope material around subsurface drainage pipe in Yinbei Irrigation District in Ningxia

作　　者：荣臻 王少丽[2] 郝瑞霞[1] 陶园[2] Rong Zhen;Wang Shaoli;Hao Ruixia;Tao Yuan(College of Water Resource Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Department of Irrigation and Drainage,China Institute of Water Resources and Hydropower Research,Beijing 100048,China)

机构地区：[1]太原理工大学水利科学与工程学院,太原030024 [2]中国水利水电科学研究院水利研究所,北京100048

出　　处：《农业工程学报》2021年第8期68-75,共8页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(52079145);国家重点研发计划项目(2018YFC1508301);宁夏重点研发计划重大项目(2018BBF02022)。

摘　　要：有效地阻止排水暗管被淤堵又能保持其稳定的透水性,是暗管排水应用中亟需解决的问题。为了深入理解排水暗管土工布外包料透水与防淤堵性能,该研究选取了常用的7种土工布,其中3种纺黏聚丙烯(Polypropylene,PP)无纺布,4种热熔纺黏丝无纺布,并对其中一种布进行亲水剂浸泡处理。以宁夏银北灌区土壤为例,基于室内土柱试验,依据达西定律,分析不同土工布防护措施下系统的流量衰减过程、土工布的保土能力以及防淤堵性能,并对比分析了亲水处理后土工布的反滤效果。结果表明,在排水初期,土体和土工布的渗透性下降,导致系统的排水流量持续变小,土体渗透性的变化会成为影响流量变化的主导因素,对流量衰减有75%以上的贡献度。土工布在亲水处理后,整体排流量提高了15%左右,其保土能力和防淤堵效果处理前后变化不大。针对该土质,热熔纺黏丝无纺布的反滤效果要明显好于纺黏PP无纺布。试验筛选出了适合该地区土壤特性的土工布,为相似土质地区暗管外包料的选择和处理方式提供了理论依据与技术支撑。Geotextiles are widely used as envelope materials in the construction of subsurface drainage systems around the world,due to the multiple product series,light weight,and convenient transportation.The complex and diverse soil quality has gradually brought out a wide variety of techniques of geotextiles for subsurface drainage pipe in the agricultural mechanization of China.However,the unreasonable choice of geotextile has resulted in severely clogged pipes of subsurface drainage in many irrigation areas,even prematurely lost the drainage function.It is highly urgent to effectively prevent the drainage pipe from being clogged,and further maintain the stable water permeability in the application of subsurface drainage.Two techniques of geotextile envelope are commonly used at present,including the ordinary spun-bond Polypropylene(PP)nonwoven and hot-melt spun-bonded nonwoven geotextiles.In this study,seven types of geotextiles were selected using two techniques,one of which was soaked with a hydrophilic agent.Taking the soil of Yinbei Irrigation Zone in Ningxia of China as an example,an indoor hydraulic permeability test was carried out to measure the flow attenuation under different geotextile protection.An evaluation was made on the soil-retaining capacity and anti-clogging performance of geotextile.The filtration property of geotextile was also compared before and after hydrophilic treatment.The research results indicated that the permeability coefficients of both soil and geotextiles decreased significantly in the early stage of drainage,resulting in a continuous decrease in the flow rate.There was a much greater decrease in the permeability coefficient,but a much lower impact on the flow rate in the geotextile,compared with the soil.The soil permeability coefficient made a great contribution to the flow change,more than 75%of flow attenuation.In general,the pore size and thickness of geotextile directly determined the soil conservation effect and anti-clogging ability.Correspondingly,large apertures and high th

关 键 词：土工布 排水 试验 渗透性 淤堵 亲水处理 

分 类 号：S276.1[农业科学—农业水土工程]