潮汐河段周期性边滩切割临界阈值与沙体输移路径——以长江福姜沙河段为例  

Critical threshold of periodic point bar scour and sediment body transport path in tidal reaches: A case study of Fujiangsha reach, Yangtze River

作　　者：王建军 杨云平 张明进 朱玲玲 李绍武 闻云呈 WANG Jianjun;YANG Yunping;ZHANG Mingjin;ZHU Lingling;LI Shaowu;WEN Yuncheng(State Key Laboratory of Hydraulic Engineering Simulation and Safety,Tianjin University,Tianjin 300072,China;Key Laboratory of Engineering Sediment,Tianjin Research Institute for Water Transport Engineering,Min-istry of Transport,Tianjin 300456,China;Bureau of Hydrology Changjiang Water Resources Commission,Wuhan 430010,China;Nanjing Hydraulic Research Institute of Ministry of Water Resources,Ministry of Transport,National Energy Administration,Nanjing 210024,China)

机构地区：[1]State Key Laboratory of Hydraulic Engineering Simulation and Safety,Tianjin University,Tianjin 300072,China [2]Key Laboratory of Engineering Sediment,Tianjin Research Institute for Water Transport Engineering,Min-istry of Transport,Tianjin 300456,China [3]Bureau of Hydrology Changjiang Water Resources Commission,Wuhan 430010,China [4]Nanjing Hydraulic Research Institute of Ministry of Water Resources,Ministry of Transport,National Energy Administration,Nanjing 210024,China

出　　处：《Journal of Geographical Sciences》2023年第6期1334-1358,共25页地理学报（英文版）

基　　金：National Key Research and Development Program of China,No.2021YFB2600500;National Natural Science Foundation of China,No.52279066;Jiangsu Water Conservancy Science and Technology Project,No.2020001。

摘　　要：The evolution of point bars in changing sections of a downstream tidal current limit is periodic. Accordingly, assessing the critical morphology and hydrodynamic characteristics of point bar scour and the sediment transport process of scour sediment bodies can support river regulation and waterway maintenance. The frequent scour of point bars in changing sections of tidal current limits within the Yangtze River directly restricts waterway stability. This study examined the Fujiangsha reach of the Yangtze River, hydrological data on sediment transport, and riverbed topography from 1950. The Jingjiang bank tail exhibited an evolutionary cycle(siltation>scour>siltation), with a primary period ranging from 3–6 years. Additionally, certain morphological and dynamic conditions were necessary for scour. The Datong station flow(Q) ranged from 20,000–40,000 m^(3)·s^(-1)for ≥180 days·yr^(-1), enabling the bank silt layers to widen. Scour occurred during flooding and was concentrated in areas 5.0–7.5 km downstream from Ebizui. When Q≥40,000 m^(3)·s^(-1), scouring occurred in the bank middle and lower reaches, whereas Q≥50,000 m^(3)·s^(-1)for >50 consecutive days, scour occurred at the tail as well. Moreover, the volume of the scour shoals increased with the number of high-flow days(≥60,000 m^(3)·s^(-1)). Bottom sand transport mainly occurred in the low-bank zone. Before the project’s second phase, the longitudinal transport of the scouring sand bodies occurred as follows: Jingjiang bank > low bank on the north side of Shuangjiansha > Fubei anabranch. During the second phase, the longitudinal transport route changed to Jingjiang bank > Fubei anabranch. The Jingjiang bank volume was also reduced;thus, its development was controlled. Owing to changes in the longitudinal transport routes, dredging should be conducted in areas where scouring sand bodies are separately transported from the tail, thereby reducing the load of dredging and maintenance for the Fubei anabranch during dry years.

关 键 词：periodic scouring critical dynamic conditions critical morphological characteristics Jingjiang bank Fujiangsha reach 

分 类 号：TV147[水利工程—水力学及河流动力学]