Performance of riffle structures on the stabilization of two successive knickpoints over a sandy bed  

作　　者：Afshin Fouladi Semnan Mohammad Reza Jaefarzadeh 

机构地区：[1]Civil Engineering Department,Ferdowsi University of Mashhad,Iran [2]Civil Engineering Department,School of Engineering,Water and Environment Research Institute,Ferdowsi University of Mashhad,Iran

出　　处：《International Journal of Sediment Research》2020年第4期377-385,共9页国际泥沙研究（英文版）

基　　金：The support of the research council of Ferdowsi University of Mashhad(FUM),Iran,[grant number 30077]during the preparation of this work is kindly acknowledged.

摘　　要：Two successive knickpoints with a 10% slope were constructed 1 m apart on a sandy bed in a rectangular flume with a longitudinal slope of 0.003.Bed erosion and knickpoint migration were studied experimentally for different discharge s.The performance of two grade-control structures-Newbury rock riffles(NRR) and cross-vane riffles(CVR)-were studied experimentally for the stabilization of each knickpoint.Both of the structures were successful in controlling the bed erosion;however,the NRR operated relatively better than the CVR for they could concentrate the flow at the middle part of the channel to produce more regular contours with less local erosion and bed settlement.The experiments demonstrated that the construction of a control structure was not only effective in the stabilization of a knickpoint but also retarded the migration of its neighboring counterpart.

关 键 词：Control STRUCTURES Cross-vane RIFFLE KNICKPOINT migration Newbury rock RIFFLE RIVERBED STABILIZATION 

分 类 号：TV147[水利工程—水力学及河流动力学]