2024年洞庭湖团洲垸溃堤过程及洪水演进模拟  

Analysis on embankment failure process and flood routing simulation of Tuanzhou embankment in Dongting Lake in 2024

作　　者：刘鑫 官学文 张俊 罗兴 张馨月 童冰星 LIU Xin;GUAN Xuewen;ZHANG Jun;LUO Xing;ZHANG Xinyue;TONG Bingxing(Bureau of Hydrology,Changjiang Water Resource Commission,Wuhan 430010,China;Middle Yangtze River Bureau of Hydrology and Water Resources Survey,Bureau of Hydrology,Changjiang Water Resources Commission,Wuhan 430010,China;Three Gorges Bureau of Hydrological and Water Resources Survey,Bureau of Hydrology,Changjiang Water Resources Commission,Yichang 443000,China)

机构地区：[1]长江水利委员会水文局,湖北武汉430010 [2]长江水利委员会水文局长江中游水文水资源勘测局,湖北武汉430010 [3]长江水利委员会水文局长江三峡水文水资源勘测局,湖北宜昌443000

出　　处：《人民长江》2024年第10期7-14,共8页Yangtze River

基　　金：国家自然科学基金长江水科学研究联合基金项目(U2240204)。

摘　　要：蓄滞洪区是长江中下游防洪工程体系中的重要一环,研究蓄滞洪区溃堤洪水演进模拟,对于防洪减灾具有重要意义。收集了2024年洞庭湖团洲垸溃堤时实测口门宽度及流量数据,分析计算了溃口流量过程,采用平面二维水动力学模型计算了溃口过程中团洲垸内的洪水演进过程,分析了垸内淹没水深、流速等致灾要素的时空变化。结果表明:①溃口发展包括下挫冲槽、横向展宽和稳定泄流3个阶段,基于流量过程推求了进入团洲垸的总水量为2.53亿m^(3),与基于库容曲线反算的水量(2.63亿m^(3))基本相当;②验证了溃口附近流量和水位过程与实测过程基本相符,团洲垸内最高水位为31.955 m,与实测水位(31.960 m)基本一致;③模型计算的淹没范围与基于遥感影像提取的范围基本一致,在计算时段末,92.7%的区域处于重度淹没状态(淹没水深超过1.5 m),最大淹没水深约为8.2 m,垸内流速均呈先增大后减小的变化趋势,各时刻(t=4 h、t=10 h、t=15 h和t=20 h)平均流速分别为0.37,0.43,0.22 m/s和0.05 m/s。研究成果可为溃堤洪水风险评估、堤防守护等提供技术支撑。Flood storage and detention areas play an important role in flood control in the middle and lower Changjiang River,so it is significant to study the simulation method of the flooding processes in the flood storage and detention areas.Based on the measured width and flow discharge data of the embankment failure at Tuanzhou embankment alongside the Dongting Lake in 2024,the discharge process at the breach was reproduced,and the flood evolution was simulated by using a two-dimensional hydrodynamic model to analyze the temporal and spatial variations of disaster-causing factors,including water inundation depth and flow velocity.The results showed that:①the development of embankment failure included three stages,namely,downward scouring,lateral widening and steady discharging;the total water volume entering the Tuanzhou embankment was estimated as 2.53×108 m^(3) based on the discharge process,which was basically equivalent to the water volume(2.63×108 m^(3))back-calculated according to the reservoir capacity curve.②The discharge and water level processes near the breach were basically consistent with the measurements,and the maximum water level in the Tuanzhou embankment was 31.955 m,which was basically consistent with the measured water level(31.960 m).③The inundation range calculated by the model was basically consistent with the range extracted based on remote sensing images.At the end of the calculation period,92.7%of the area was in severe inundation(the inundation depth>1.5 m),the maximum inundation depth was about 8.2 m,and the flow velocity in the embankment increased first and then decreased,with the average flow velocities at each time(t=4 h,t=10 h,t=15 h and t=20 h)were 0.37,0.43,0.22 m/s and 0.05 m/s.The results can provide technical support for the risk assessment and flood control of embankment failure.

关 键 词：堤坝溃决 洪水演进 水动力学模型 团洲垸 洞庭湖 蓄滞洪区 

分 类 号：TV147[水利工程—水力学及河流动力学]