摘要
天然河道受水沙条件、堤防工程等因素的影响,其平面形态常呈现河道展宽与缩窄的特征。以宽窄渐变河段的洪水过程与典型断面冲淤变化特性为基础,利用数值模型探讨了河宽渐变对水流运动特性的影响,并进一步分析了局部区域冲淤的水动力机理。分析结果表明:不同的洪水过程峰量大小及历时特征,将显著影响其涨退水强度;不对称的河道展宽与缩窄将改变断面流速峰值的分布;河床断面的冲淤特性取决于洪水过程的流速变化与床沙临界起动流速的大小。
The wide gradual reach is a common form of natural rivers because of the impacts of flow and sediment conditions, and man- made projects. Based on the flood process and erosion and deposition of hydrological observational cross section in a gradual width river, the hydrodynamic characteristics was simulated and analyzed by means of a two-dimensional flow model. The comparison between ob- servation and simulation showed that the intensities of increase and decrease of flood depend on the value and duration of flood process, and the velocity distribution at any cross section often change with the variation of asymmetry river wide, which affects the bed deforma- tion in the whole reach considering tile effect of sediment critical incipient velocity.
出处
《四川大学学报（工程科学版）》
EI
CAS
CSCD
北大核心
2014年第2期14-19,共6页
Journal of Sichuan University (Engineering Science Edition)
基金
国家自然科学基金资助项目(41171016)
关键词
渐变河道
堤防工程
洪水过程
河床演变
gradual channel
embankment project
flood process
channel evolution
