废黄河地涵工程冲淤成因及其防治措施

近年来,废黄河地涵工程出现冲淤现象,对防洪和工程安全均产生巨大隐患。通过模型试验分析了废黄河上游引河段的水流流动情况及主要冲刷区和淤积区的位置和面积,利用加丁坝挑流方式,改善上游水流状态,同时利用Flow-3D软件对地涵工程及其上下游河道进行三维水动力数值模拟。结果表明,地涵工程上游左岸有回旋区及低速区,极易造成淤积,而在河道中央及靠右岸的区域,水流流速较快,容易产生冲刷现象;建议采用3种方案交替运用的方式来进行控制,同时添加两道斜向下游的丁坝,对改善河道流态和防冲减淤具有重要的工程参考意义。

Scour and Siltation Causes and Its Prevention Measures of Abandoned Yellow River Culvert Project

In recent years, the phenomena of siltation and scour was appeared in the abandoned Yellow River culvert project, forming the huge risk for flood control and engineering safety. The flow situation, location and area of the main scour and siltation regions in the upper reaches of the abandoned Yellow River were analyzed by using model test. The flow pattern of the upstream flow was improved by using the method of spur-dike. Three-dimensional hydrodynamic simulation of the culvert project and its upstream and downstream channel were carried out. The results show that there exists raceway and low velocity zone on the upper left bank of the culvert project and it is prone to siltation; while flow velocity is faster on the middle of the river and right bank and it is prone to scour. It is suggested that the three schemes be used alternately to control them. At the same time, it has important engineering reference significance for improving river flow pattern and preventing scour and siltation by adding two inclined spur-dikes.