深圳河近期回淤特征及回淤机理研究  

Study of recent back-siltation characteristics and mechanisms of Shenzhen River

作　　者：冯志勇 吴门伍 吴小明 胡阳[1] 谈广鸣[1] FENG Zhiyong;WU Menwu;WU Xiaoming;HU Yang;TAN Guangming(State Key Laboratory of Water Resources and Hydropower Engineering Science,Wuhan University,Wuhan 430072,China;Pearl River Scientific Research Institute,Pearl River Water Resources Commissi on,Guan gzhou 510611,China)

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072 [2]珠江水利委员会珠江水利科学研究院,广东广州510611

出　　处：《武汉大学学报（工学版）》2020年第11期941-949,共9页Engineering Journal of Wuhan University

基　　金：国家重点研发计划项目(编号:2018YFC0407800)。

摘　　要：通过不同时期的实测地形,研究了环保清淤工程实施后深圳河的回淤分布特征。利用Delft3D建立了同时考虑悬沙和浮泥运动的深圳河湾平面二维水沙数学模型,探讨了回淤机理和回淤泥沙来源。实测资料表明清淤工程实施后深圳河回淤明显,1 a后的回淤量达20.8万m^3,占总清淤量的41.7%。洪季回淤量远大于枯季。模型计算显示清淤工程实施后河道内断面平均流速大幅降低,其中洪季减小量大于枯季减小量。平均落急流速只有工程前的40%,是导致清淤河段快速回淤的直接原因;回淤泥沙来源模拟显示潮流输沙对初期回淤量的贡献最大,达61.9%。随着洪季上游来沙量的增加,上游来沙对回淤量的贡献率增加至46.8%,成为工程河段淤积的主要来源。Based on the measured bathymetric data at different periods,the back-siltation distribution characteristics of Shenzhen River after implementation of the environmental protection dredging project was explored.A two-dimensional numerical model that considers suspended sediment and mud transport was established using Delft3 D,and the siltation mechanisms and silting sources were investigated.The field measurements data indicated that obvious back-siltation occurred in Shenzhen River after the implementation of the dredging project,with the cumulative siltation volume reaching 2.08×10^5 m^3 in one year after the project,accounting for 41.7% of the total dredging volume.The back-siltation volume occurred in the flood season was much greater than that in the dry season.Modeling results showed that the cross-sectional average flow velocity significantly decreased after the dredging project,and the velocity reduced greater in the flood season than that in the dry season.The mean ebb velocity was only 40% of that before the dredging project,which was the immediate cause for rapid back-siltation in the dredging reach.The back-siltation sediment source modeling results indicated that the sediment transport by tidal currents was the largest contributor to the initial backfill,with the contribution rate of 61.9%.With the increasing upstream sediment input during the flood season,the contribution rate of upstream sediment input to the total back-siltation volume increased to 46.8%,which became the main source of back-siltation in the dredging reach of the river.

关 键 词：泥沙回淤 数学模型 清淤工程 深圳河 

分 类 号：TV148[水利工程—水力学及河流动力学]