荆江河段水沙条件与主流线特征关系研究  

Relationship between flow and sediment regime and changes of main streamline in Jingjiang reach

作　　者：刘亚[1] 李义天[2] 孙昭华[2] 陈飞 

机构地区：[1]长江科学院,湖北武汉430010 [2]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072 [3]长江航道规划设计研究院,湖北武汉430011

出　　处：《水利水运工程学报》2011年第2期77-83,共7页Hydro-Science and Engineering

基　　金：国家自然科学基金资助项目(50609018)

摘　　要：荆江河段的主流变化主要表现为弯曲分汊段的主支汊交替及单一弯道段深泓半径的变化,综合考虑两者关系,提出了能描述荆江分汊段及单一弯道段主流线特点的无量纲常数——弯曲特征数r,并针对同一河段分析了汛期平均流量、洪峰变差系数、年输沙量及输沙指数等水沙条件变化与主流线变化的对应关系.结果表明:汛期平均流量较小、水流相对饱和度低、来水来沙过程较为均匀使得滩槽高差较小,横断面向宽浅发展,从而减弱河道对水流的约束,弯曲特征数较小,主流顺直;反之主流向弯曲发展.The main streamline of Jingjiang reach changes in the form of alternation of main tributary branches and radius of thalweg in bends.To describe the characteristics of mainstream line in bifurcated and curved reaches,this paper presents a dimensionless coefficient： sinuosity eigenvalue r.Correlation between r and other eigenvalues（such as dispersion of flood flow,sediment transport index,etc.） obtained by hydrological statistics reveals that less of average flood,uniformity of flow and incoming sediment will lead to less difference of elevation between bottomland and trough,and when the cross-section becomes wide-shallow,it will weaken the capability of water binding and minish the sinuosity eigenvalue,thereby,the main streamline becomes straight,otherwise curved.

关 键 词：河床演变 水沙条件 水流动力轴线 荆江河段 

分 类 号：TV147[水利工程—水力学及河流动力学]