水利学报Issue(7)：836-843,8.DOI:10.13243/j.cnki.slxb.20150187
黄河源草甸型弯曲河流的悬臂式崩岸机制
Cantilever bank failure mechanism of meadow meandering river in the Yellow River source region
摘要
Abstract
Riparian meadow plays a key role on controlling bank failure and maintaining channel meander⁃ing of meadow meandering rivers in source region of the Yellow River. Field investigation in 2011-2014 was conducted on root system of riparian vegetation, geometric dimension of slump blocks, and physical characteristics of root-soil composite in the Lanmucuoqu River. Root tensile strength across collapsing sur⁃face was measured by in situ pull-out test in order to study bank failure mechanism. Root system of ripari⁃an meadow has a great contribution to reinforce soil mass that is an inherent factor to restrict near-bank erosion and bank failure. Near-bank flow laterally erodes sand and gravel bed beneath the root system until the upper root-soil composite is hanging to reach a critical condition under self-weight action. If exceeding the critical condition, a long crack penetrating the root-soil composite along river bank induces bank fail⁃ure with a slump block toppling bank slope. Meadow bank failure is dominated by cantilever tensile failure pattern. Results indicate that slump block thickness has a logarithmic function with root length,and the vol⁃ume of slump block increases with root length increasing. By the new bank failure pattern of meadow mean⁃dering river, a critical equilibrium equation of moment of force was derived to describe the cantilever ten⁃sile failure of root-soil composite, and further to obtain a critical width expression of slump blocks. The critical width is the function of root length and tensile strength increment by root reinforcement. The predict⁃ed value of critical width is in good agreement with the measured value.关键词
弯曲河流/滨河草甸/崩岸/崩塌块/抗拉破坏Key words
meandering river/riparian meadow/bank failure/slump block/tensile failure分类
建筑与水利引用本文复制引用
朱海丽,李志威,胡夏嵩,李国荣,宋路,付江涛..黄河源草甸型弯曲河流的悬臂式崩岸机制[J].水利学报,2015,(7):836-843,8.基金项目
国家自然科学基金资助项目（41302258）；青海大学中青年科研基金资助项目（2012-QGY-5）；青海大学“123高层次人才培养工程”资助项目；青海大学“地质资源与地质工程创新团队”（4056051201）；中国博士后科学基金资助项目 （）
