| 摘要: |
| 堤防决口抢险需以水流水力学特性为依据，封堵方法亦直接影响其封堵效率。首先对决口水流遇障碍物的洪水演进过程进行模拟，将水深计算结果与Biscarini等的试验数据进行对比，结果吻合较好，验证了数值模型的可靠性、准确性。以上饶市某一河道为例，基于FLOW-3D软件建立了堤防决口水流模拟的三维数值模型，对立堵法、平堵法封堵决口进行数值模拟，得到封堵过程中决口附近水位场和流速场分布规律。数值模拟结果显示：该堤防决口进口附近立堵法、平堵法块石前水位壅高明显，流速增大，最大水深分布在决口靠右位置，最大流速分布在决口靠左位置。根据决口附近流速分布规律，封堵时建议先对左侧决口堤脚进行裹头处理，而后可考虑采用大粒径块石单体抛投以降低流速，再采取群体抛投方式进占合龙。所用模拟方法和数值模型可为堤防抢险及制定堤防决口封堵方案提供参考。 |
| 关键词: 堤防决口 封堵方法 水力学特性 FLOW-3D |
| DOI： |
| 分类号:TV551.2 |
| 基金项目:国家自然科学基金资助项目(51269019，51469015)；广东省水利科技创新基金资助项目（2014-08） |
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| Hydraulic characteristics of levee breach closure |
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LI Huokun1, ZENG Zhichao1, DENG Bingmei1, ZHANG Lirong2, LI Yizhong2
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1.School of Civil Engineering and Architecture, Nanchang University, Nanchang;2.No. 2 General Team of Armed Police Hydropower Troops, Nanchang
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| Abstract: |
| The emergency protection of the levee breach is based on hydraulic characteristics of water flow, and the closure methods directly affect the closure efficiency. First, the flood evolution process of the breach flow was simulated, and the water depth calculation results were compared with the experimental data given by C. Biscarini. The results agree well with the experimental data, which verifies the reliability and accuracy of the numerical model. Based on FLOW-3D software, a 3D numerical model for dike breach flow simulation of a river in Shangrao city was established, and the breach closure process was simulated respectively by the vertical closure method and the horizontal closure method. The water level and velocity field distribution law near the breach during closure process were obtained. The numerical results show that the water level obviously increases and the flow velocity increases in front of the block stone by the vertical closure method or the horizontal closure method, and the maximum velocity and water depth are distributed respectively in the left and right positions near the breach. According to the velocity distribution law near the breach, wrapped dike head measures should be taken on the left breach of dike toe, then the flow velocities may be reduced by costing large-size block stones, one by one and finally a group casting way would be taken for the closure. In this paper, the numerical model and simulation methods can provide a reference for dike emergency protection and dike breach closure. |
| Key words: levee breach closure method hydraulic characteristics FLOW 3D model |
