中文摘要：

河流冰塞是寒冷地区河流的共性问题,弯槽段易于卡封是客观存在的现象,但对其形成机理的认识尚有待探索.借助于实验室的试验水槽,通过改变水流条件和冰流量条件,研究了弯槽段冰塞形成和厚度分布的规律.结果表明：当弯槽段先铺有模拟冰盖时,初始冰塞头部向下游推进的速度随水流的Fr增加而增加;当在弯槽尾部加上模拟的初封条件时,水流条件的变化可以产生冰塞发展的两种不同顺序,提出了实验室条件下的弯槽段冰塞体形成与否的临界Fr数.

英文摘要：

Ice jam is a common phenomenon for rivers in cold regions. Lodgment and gorging can easily occur especially in curved channels. The formation of ice jam and its thickness distribution in curved channels were not fully understood. By changing the flow conditions and ice discharge in a flume in the laboratory, the ice jam formation and its thickness distribution was studied. The experi- ment results showed that when model ice cover was pre-placed in the curved channel, the advancing rate of the initial front edge of the ice jam increased with the increase of the channel flow Froude number （Fr）. When model initial ice jam was pre-placed downstream of the curved channel, it was found that there were two kinds of sequences in ice jam forming, jam forming from upstream to downstream or reverse, depending on the channel flow condition. The threshold Fr numbers for whether an ice jam would form were established for this curved channel in the laboratory.