变坡潜堤周围水流结构对软体排破坏的影响因素分析

Influential factors of flow structure around variable slope submerged dike on failure of soft bank

针对变坡潜堤周围水流结构复杂多变的问题,依托和畅洲潜堤工程,分析潜堤地形冲刷、软体排破坏原因。采用资料搜集和模型分析的方法,归纳冲刷部位堤顶高程与水位、汛期的相关性,分析水动力特性。得出以下影响因素:越堤流和绕堤流组合水流强劲,长江大流量及快速退水,二元土层结构河床稳定性差。采用抛填砂袋和抛填块石加固措施,可抑制冲刷发展。

The structure of water flow around the submerged dike with variable slope is complex and changeable.Based on the Hechangzhou submersible dike project,this paper analyzes the reasons of topographic scour and soft bank damage for the submersible dike.Based on data collection and model analysis,this paper summarizes the correlation between the elevation of the dike top and water level and flood season at the scour site,and analyzes the hydrodynamic characteristics.The following influential factors are obtained:strong combined flow over the dike and around the dike,large flow and rapid retreat of the Yangtze River,and poor stability of the riverbed of the binary soil layer structure.The scour development can be restrained by using the sandbag and stone.