2020年汛期鄱阳湖湖区圩堤渗漏险情统计特征分析

Statistical Analysis of Dike Seepage in Poyang Lake District During 2020 Flood Season

2020年鄱阳湖流域遭遇历史性特大暴雨袭击,水位持续上涨,多处圩堤出现管涌等渗漏险情。通过对2020年汛期鄱阳湖湖区廿四联圩发生的104处主要渗漏险情、河道水文资料及堤基地质资料的梳理分析,探讨了渗漏险情发生与河道水位以及堤基地质条件之间的内在关联性。研究表明,当河道水位超过警戒水位后,会有超过90%的渗漏等险情发生,尤其是当水位达到历史最高水位前后,险情密切集中,防汛形势十分严峻。计算各地质类别险情发生比率,最后得出圩堤发生险情状况与地质条件有较好的对应性,多数险情发生在堤基地质条件不好的堤段,尤其地质分类为较差(C)和差(D)的地段,险情比较容易发生。

The Poyang Lake Basin experienced the heaviest rainstorm exceeding the historical record,and the water level continued to rise,leading to seepage hazards such as piping in many dikes in 2020.Based on the analysis of 104 major seepage hazards,river hydrological data and dike geological data in 24 th Lianwei in Poyang Lake during the flood season in 2020,the internal correlation between seepage hazards and river water level and geological conditions of the dike foundation was discussed.The results reveal that more than 90%seepage and other dangers occurred when the river water levels exceeded the warning level,the dangers were especially concentrated when the water levels reached the highest level and the flood control situation was very severe.It is concluded that the hazard situation of the dike has a good correspondence with the geological conditions by calculating the occurrence rate of each geological hazard.Most dangerous situations occurred in the sections of the dike base with poor geological condition,dangerous situations were specifically more likely to be occurred in the sections classified as C and D.