中文摘要：

长江中游河道岸滩侧蚀现象普遍,易对航道稳定形成不利影响,深入研究岸滩侧蚀冲刷机理及其航道响应过程具有重要意义。建立了考虑相邻土体影响的黏性岸滩侧蚀坍塌力学模式,以长江中游太平口水道为例,基于局部网格可动技术,构建了岸滩侧蚀及其河床冲淤变化的三维水沙动力学模型;在模型验证相似的基础上,分析了清水冲刷条件下腊林洲边滩侧蚀对太平口水道航道格局的影响。研究结果表明：模型可较好地模拟由岸滩侧蚀所引发的河势演变过程;上游来沙减少后,太平口水道河床以及未守护低滩部位将进一步产生冲刷;腊林洲边滩稳定与否,对太平口水道＂南槽-北汊＂航道格局的稳定具有重要作用。

英文摘要：

Riverbank erosion occurs frequently on the middle Yangtze River,which may result in the instability of the channel navigation.A new riverbank erosion model for the cohesive material was developed by considering the effects of adjacent cohesion.On the basis of 3-D flow and sediment transport model and the mechanisms of riverbank erosion,a 3-D morphological model for the Taipingkou Waterway on the middle Yangtze River was developed by using the adaptive grid system.The 3-D model was calibrated by the observed data,and the simulated results agreed with the measured data.The influences of riverbank erosion processes on the navigation conditions were simulated by the numerical model.The developed model is able to calculate the complex morphological changes due to bank erosion.Bed degradation and bank erosion are enhanced with less sediment load input.Simulated results indicated that the riverbank stability of Lalinzhou is critical for the stability of navigation conditions on the Taipingkou Waterway.