长江下游窝崩机理及其治理技术  

Mechanism and treatment technology of nest-shaped bank collapsing in the Lower Yangtze River

作　　者：张幸农[1,2] 假冬冬 应强[1,2] 陈长英 ZHANG Xingnong;JIA Dongdong;YING Qiang;CHEN Zhangying(Nanjing Hydraulic Research Institute,Nanjing 210029;State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Nanjing 210029;Yangtze Institute for Conservation and Development,Nanjing 210098)

机构地区：[1]南京水利科学研究院,南京210029 [2]水文水资源与水利工程科学国家重点实验室,南京210029 [3]长江保护与绿色发展研究院,南京210098

出　　处：《中国防汛抗旱》2022年第9期1-6,共6页China Flood & Drought Management

基　　金：国家自然科学基金项目(U2040215、52079080)。

摘　　要：窝崩是水土交互作用下的岸坡失稳破坏现象,具有随机性强、形成时间短、土体崩塌量大的特征,发生后出现“Ω”形或半圆形窝塘。窝崩机理复杂、规律难偱,有两种类型:(1)伴随水流冲刷而出现的大块土体持续崩塌;(2)因土体内存在液化层而出现的大块土体侧向滑移。窝崩多出现在汛期和汛后退水期,与来水来沙条件关系尚不明显,总体上呈现南岸多、北岸少的分布特征,并且较易出现在弯曲凹岸、洲头洲尾和边界突变段。目前窝崩的模拟技术和预警技术尚不成熟,治理采用窝塘抢险与后续复建相结合,通过设置临时挡洪子堤防范江水倒灌,确保防洪安全;通过“守两肩、固周边、先促淤、后封口”等工程措施实施窝塘抢险。针对长江下游窝崩现象,论述其成因机理和分布规律,并评述相应的治理技术。Nest-shaped(or arch) bank collapsing in the Lower Yangtze River is the instability and failure phenomenon of bank slope under the interaction of water and soil. It has the characteristics of strong randomness, short formation time and large amount of soil collapse. After the occurrence, a " Ω " shaped or semi-circular collapsing appears. The mechanism of collapsing in is complex and the law is difficult to find out. There are two types:(1) the continuous collapse of large soil mass accompanied by water scouring;(2) Lateral sliding of large soil mass due to liquefaction layer in soil mass. Most of the cave collapses occur in the flood season and the flood retreat period, and the relationship with the coming water and sediment conditions is not obvious. On the whole, it shows the distribution characteristics of more in the south bank and less in the north bank, and it is more likely to occur in the curved concave bank, the head and tail of the continent and the boundary mutation section of main channel of Yangtze River. At present, the simulation technology and early warning technology of arch collapse are not mature. The treatment technology is the combination of cave pond rescue and subsequent reconstruction. The temporary flood retaining embankment is set to prevent the river water from flowing back and ensure the flood control safety;The emergency rescue of the pit pond was implemented through en-gineering measures such as "guarding two shoulders, consolidating the periphery, promoting siltation first and sealing later". In view of the phenomenon of arch collapse in the lower reaches of the Yangtze River, this paper discusses its formation mechanism and distribution law, and comments on the cor-responding control technologies.

关 键 词：窝崩 机理 治理 长江下游 

分 类 号：TV882.2[水利工程—水利水电工程] TV853