废黄河立交工程防冲减淤模型试验及数值模拟

Model test and numerical simulation research on anti-scour and silt relief of interchange project on abandoned Yellow River channel

废黄河立交工程自1999年7月建成以来,地涵管理范围内河道冲淤现象严重,对防洪产生了巨大的安全隐患。针对该工程上游引河段的冲淤情况,通过物理模型试验和数值模拟相结合的方法,模拟地涵工程引河段的水流流态特征和悬沙场分布情况,分析了上下游河道冲淤的成因及主要冲淤区的位置。结果表明:地涵工程上游左岸水动力较弱,易造成淤积,右岸流速较快易产生冲刷现象,长期运行后会在上游引河段形成弯道水流,而在下游河道的右岸的水动力较弱,是主要的淤积区域。在模型试验中提出增加两道丁坝来改善河道流态达到防冲减淤的目的,试验结果表明改善效果较好。

Since the operation of the abandoned Yellow River interchange Project in July 1999,the scouring and silting of the river course around the culvert project has been serious,which has caused huge potential safety hazards for flood control.Aiming at the scouring and silting situation of the upstream diversion reach of the project,this paper simulated the flow pattern characteristics and the distribution of suspended sediment field of the diversion reach of the culvert project through the combination of physical model test and numerical simulation.The causes of scouring and silting of the upstream and downstream channel were analyzed,as well as the location of the main scouring and silting areas.The results showed that the weak hydrodynamic force on the left bank of the upper reaches of the culvert project was weak,causing siltation,and the fast flow rate on the right bank cause scouring phenomenon.After long-term operation,a bend flow will be formed in the upstream diversion reach.While the weak hydrodynamic force on the right bank of the downstream channel form a main silting area.After the model test,an optimum scheme of adding two spur dikes to improve the flow pattern of the river was put forward,and the experimental results showed that the improvement effect was good.