泥沙起动概率概念及其计算方法

Concept and computing method of sediment incipient motion probability

泥沙起动是推移质输沙研究的基础,确定性和随机性研究是其常用的研究方法,二者各有优势和不足。Einstein是泥沙起动随机性理论的重要开创者,由于泥沙起动概率概念较为抽象以及其数据获取较为困难,后续研究者往往批判继承其理论体系,甚至造成部分误解。本文详细回顾了泥沙起动概率模型的发展历程,重新解读了泥沙起动概率这一抽象概念,并提出了一种获取泥沙起动概率数据的计算方法。研究表明,Einstein泥沙起动概率模型与本文搜集资料计算所得的泥沙起动概率数据吻合良好。文末对部分研究者认为Einstein起动概率模型存在的三大缺陷进行了回应,并讨论修正了Einstein落淤率模型,认为基于该模型的推移质输沙率公式的适用性更强。

Sediment incipient motion is the basis of the bed-load transport study.The deterministic and probabilistic research methods which both have advantages and disadvantages,respectively,are used in this issue frequently.Einstein was an important pioneer of stochastic theory of sediment incipient motion,however,the theoretical system was critically inherited and even partially misinterpreted because of the ambiguity definition and the difficulty in data collection of sediment incipient motion probability.In present paper,the development process of probability model of sediment incipient motion was reviewed in detail,the ambiguity concept of sediment incipient motion probability was newly interpreted,and a computing method of data collection of sediment incipient motion probability was proposed.Result shows that Einstein′s probability model of sediment incipient motion has no material weakness,and the so-called three major defects in Einstein′s model suspected by some researchers was answered.Finally,the deposition rate in Einstein′s bed-load transport model was modified,and the new bed-load transport formula based on the modified deposition rate model has stronger applicability in both low and high bed-load transport rates.