水利学报2018，Vol.49Issue(3)：271-281,11.DOI:10.13243/j.cnki.slxb.20170473
岸坡崩塌条件下弯道环流与水流剪切力的变化特征
Characteristics for circulating currents and water-flow shear stress under the condition of bank slope collapse
摘要
Abstract
Riverbank collapse is a major form of bank slope instability because of hydrodynamic forces,which is the interaction result of the river water flow and bank slope.Eight series of experiments were carried out in a bend flume to simnulate the process of bank collapse and river topography in small scale.Cohesive bank material from Dengkou site of the Ning-Meng river reach of the upper Yellow River was used to make the bank slope model.The experiments pay attention to the features of changes in three aspects of water-sediment-riverbed,such as water level,near-bank flow velocity distribution,particle size and riverbed erosion and sedimentation,and the distribution characteristics of water shear force distribution during the collapse of sticky bank slope are revealed and analyzed.The bed shear stress was calculated and found that the shear stress of the head and tail of the collapse body increased suddenly,which formed a larger shear foree zone.The tail shear stress is greater than the head shear stress,and the tail is formed eddy current and the flow velocity is chaotic,which increases the local sediment transport capacity of the river bed to speed up the decomposition of the collapse of the body.The paper analyzes the hydrodynamic change characteristics of the bank slope collapse,which provides not only the basis for cohesive bank sediment transport model,but also the reference for the planning and design of river bank construction.关键词
岸坡崩塌/黏性岸坡/水槽实验/弯道环流/水流剪切力Key words
bank collapse/cohesive bank material/flume experiment/circulating currents/water-flow Shear stress分类
建筑与水利引用本文复制引用
舒安平,周星,余明辉,段国胜,朱福杨..岸坡崩塌条件下弯道环流与水流剪切力的变化特征[J].水利学报,2018,49(3):271-281,11.基金项目
国家自然科学基金项目(11372048) （11372048）
国家重点基础发展发展计划项目(2011CB403304) （2011CB403304）
