中文摘要：

不连续宽级配床沙在天然河道中广泛存在,作为非均匀沙的特殊类型,其床面阻力与一般意义上的非均匀床面相比具有不同的特性。本文通过水槽试验对不连续宽级配床面阻力特性进行了探讨,引入峰度系数表征粗糙床面床沙粒径的非均匀性,将不连续宽级配床面与连续宽级配床面统一起来,根据试验数据拟合得到不连续宽级配床面阻力系数表达式,具有较好的精度。

英文摘要：

Discontinuous wide-gradation sediment widely exists in natural rivers as a specific type of non-uniform sediment.It has different flow resistance with rough bed while compared with traditional non-uniform sediment.The flow resistance of rough bed with discontinuous wide-gradation sediment was studied by flume experiment.In the paper,the bimodality parameter is introduced to express bed nonuniformity,so as to unify the rough bed with discontinuous and continuous wide-gradation sediment.Moreover,the resistance coefficient of rough bed with discontinuous wide-gradation sediment was fitted by experiment data with good accuracy.