漫水丁坝坝头床沙起冲流速研究

设计丁坝时，漫水丁坝坝头床沙起冲流速是漫水丁坝局部冲深计算的基础，迄今为止，有关这方面的研究文献所见甚少。为探索有关规律，寻找工程设计的依据，对缓流时的漫水丁坝坝头床沙起冲流速进行了尝试性的试验研究，对部分影响因子进行试验分析。研究表明：坝长及坝高增加，起冲流速减小，局部冲深增大；床沙中值粒径及水深增加，起冲流速增大。在分析基础上，提出了漫水丁坝坝头床沙起冲流速的计算办法。

STUDY OF INITIAL SCOUR VELOCITY OF BED SAND AROUND SUBMERGED SPUR DIKES

The initial scour velocity of bed sand around submerged spur dikes is the basis for calculating the local scour depth around spur dikes,and the papers about computing the depth is rarely found up to now.Exploratory experiments and analyses are introduced herein to study the initial scour velocity of bed sand around submerged spur dikes and some factors influencing the velocity.Results show that the scour depth is raised when the length and height of dam increase and the initial scour velocity increase when the sand median diameter and water depth are enlarged.Then,the calculating method of initial scour velocity of bed sand around submerged spur dikes is suggested.