摘要
冲积河流非均匀沙表层床沙粒径组成是影响水流阻力、输沙及河床冲淤的重要因素.表层床沙组成随着冲淤及与深层床沙不断交换而调整变化.本文分析提出沙波运动是床沙交换最基本最普遍的原因,提出了随冲淤及床沙交换床沙调整变化的计算关系.根据作者及其它水槽试验和河流实测沙波资料,文中总结得出了沙波高度、沙波运动速度及周期的新的计算公式,可用于估算床沙活动交换层厚度及交换速度,也可用于其它方面的分析计算.
The size distribution of non-uniform sediment on alluvial stream bed surface greatly affects the flow friction, sediment transport and fluvial processes. It changes with the scour or the deposition of river bed and the exchanges of bed material which are caused by the movement of sand waves.The new relationships for predicting the change of size distribution of bed material, the height A, the velocity Vsx and the movement period T of sand waves and the exchange depth of bed material are presented. The parameters of sand waves all depend on dimensionless shear strees due to grain resistance θ*f, median diameter D50 and relative flow depthH/D50 For the natural rivers, the dimensionless velocity is proportional to is inversely proportional to increases when θ*f<0.7 and decreases when θ*f>0.7 and equals 25000 for θ*f=0.7
出处
《泥沙研究》
CSCD
北大核心
1992年第4期14-23,共10页
Journal of Sediment Research
