Abstract: Taking the Xu-Yu section of Yangtze Ｒiver as the prototype，the generalized model with successive bends has been established，and the fixed bed water flow test has been carried out． The results show that the boundary conditions of the transition section has significant influence on the distribution of transverse gradient in successive bends． The distribution of transverse gradient in the successive bends within compound section is the form of non-full symmetry，which is different from the full symmetry distribution of the curved roof in the single rectangular bend． The transverse gradient of export is bigger than that of entrance in the successive bends． The formulas of maximal transverse gradient and the distribution of transverse gradient in the whole successive bends are built，where the morphology factor of side shoal is reflected．

Key words: successive bends, compound section, transverse slope

摘要： 以长江叙渝段为原型建立连续弯道概化模型，进行定床水流试验。结果表明: 过渡段的边界形态对连续弯道横比降分布存在明显影响，与单一矩形弯道中以弯顶呈完全对称分布特征不同，弯曲放宽复式河槽边界条件下弯道的横比降呈不对称分布，其后弯区域比降大于前弯。建立了反映边滩形态因子的最大横比降和全弯道横比降分布公式。

关键词: 连续弯道, 复式河槽, 横向比降