浙江台州湾金清潮滩水力泥沙特性

The Characteristics of Hydro-Sediment of Jinqing Tidal Flat in Taizhou Bay, Zhejiang

本文分析了潮滩水力泥沙特性,认为在上部潮滩带潮流向受地形影响为往复流,水沙过程受潮波驻波影响为剧变过程;在下部潮滩带,潮流向受浅海潮流向和地形的共同作用为准旋转流,水沙过程为渐变过程.文章分析了水力泥沙的沿程变化和水沙关系,认为中潮位以上潮流加速减小,含沙量加速升高,水体含沙量(S)与流速(u),水深h和悬沙颗粒沉速(ω)的关系为:S=0.41((u^3)/(gωh))^(0.35) 该式在淤泥质潮滩正常天气条件下有广泛的适用性.

Based on the systematic measured data, this paper analyses the hydro-sediment characters of Jinqing tidal flat in Taizhou Bay, Zhejang. It is suggested that the tidal flat be divided into two parts according to the hydro-sediment characters. On the upper tidal flat, the tide flow moves toand fro, influenced by the tidal flat bedforms, and the hydro-sediment processes are intensely-changed processes affected by the standing tide wave. On the lower tidal flat, the tidal flow is quasi-rotating current affected by Taizhou Bay rotation current and the tidal flat bedforms as well. The hydro-sediment processes are gradually-changed processes. It also considers the change of the hydro-sediment on the flood and ebb way and the relation between the sediment concentration and hydraulic essential elements. It is suggested that the tidal flow reduces and sediment concentration increases landwards, and this tendency accelerates from the midtide level line to coastal line. The relation between the sediment concentration (S) and the tidal velocity (u), water depth (h) and suspended sediment settling velocity (ω) can be expressed as : This expression can be widely used on muddy tidal flat, especially in the condition of normal weather and weak wave action.