天然河道不连续宽级配床沙特性及形成条件探讨  

Characteristics and Formation Conditions of Discontinuous Widely-Graded Sediment in Natural River Course

作　　者：魏丽[1,2] 卢金友[3] 徐海涛[3] 

机构地区：[1]中国科学院山地灾害与地表过程重点实验室,成都610041 [2]中国科学院水利部成都山地灾害与环境研究所,成都610041 [3]长江科学院,武汉430010

出　　处：《长江科学院院报》2012年第10期6-10,15,共6页Journal of Changjiang River Scientific Research Institute

基　　金：国家自然科学基金(50879006);中国科学院知识创新工程重要方向项目群(KZCX2-YW-JS305)

摘　　要：选取我国有代表性的几个河段对不连续宽级配床沙特性及形成条件进行了初步探讨,为不连续宽级配床沙运动规律研究提供了基础。认为不连续宽级配床沙特性为:泥沙粒径范围很宽,某一粒径范围泥沙较少甚至缺失,床沙粒径重量百分数具有明显的双峰分布特征。不连续宽级配床沙形成的一般条件为:河床床沙本身具有一定的不均匀性,河床有一定的覆盖层厚度,上游具有补给性的来沙条件,河段水流速度具有一定的变化幅度。With three typical natural river courses in China as case study, we preliminarily discussed the characteristics and formation conditions of discontinuous widely-graded sediment, providing basis for researching discontinuous widely-graded bed load transport. It＇ s believed that the characteristics of discontinuous widely-graded sediment are as follows： the sediment particle size varies in a wide range; sediment of a certain size is in a small amount or even in absence ; and the weight percent of bed sediment exhibits a clear bimodal distribution. The formation of discontinuous widely-graded sediment is based on three conditions： non-uniform bed sediments and thick riverbed cov- er, sediment supplies from the upstream, and varying flow velocity in the river course.

关 键 词：不连续宽级配床沙 床沙特性 床沙粒径 形成条件 

分 类 号：TV142.1[水利工程—水力学及河流动力学]