天然河道水流挟沙能力研究

Sediment-carrying capacity in natural rivers

天然河道水流挟沙能力的确定对于利用数学模型来模拟泥沙运动和河床变形具有重要意义。本文在收集大量天然河流实测资料的基础上,对长江、汉江、塔里木河干流、黄河以及三门峡水库的水流挟沙能力进行了分析研究,选定了既适合于低含沙河流也适用于高含沙河流水流挟沙能力的计算公式,探讨了确定挟沙能力系数和指数的方法,避免了利用数学模型计算时系数取值的不确定性,提高了数学模型应用于不同天然河流的适应能力。研究表明,韩其为的高低含沙量统一的挟沙能力公式可以适用于各种不同的天然河流,系数取值稳定,且容易确定。

Correct calculation of sediment-carrying capacity in natural rivers is important for using mathematical models to simulate sediment transport. Based on large quantity field data, this paper firstly analyses the characteristics of sediment transport in the Yangtze River, Hanjiang River, Tarim Stem River, the Yellow River and Sanmenxia reservoir. A formula by Han （2003） is then rated by these data. The rating result shows the formula could properly calculate sediment-carrying capacity for both low and high sediment-laden flows. Finally some guidelines for estimating the related coefficients in the formula are given, so the uncertainty of selecting values for coefficients can be avoided. The applicability of using models to simulate sediment transport in natural rivers is therefore improved.