沙河密集桥梁群对河道行洪累积效应研究

城市防洪河道中桥梁群的建设,改变了河段的流势、流速和水位,壅水叠加效应十分明显,加大了城市防洪压力。以河南省漯河市城区跨沙河高密度桥梁河段为研究对象,通过建立数学模型,分别研究了单桥9种工况和多桥12种工况壅水叠加对河道行洪的影响。根据研究结果绘制了桥梁壅水高度与壅水长度关系曲线,拟合出单桥和多桥工况下上游河段壅水高度计算公式,为编制城市跨河桥梁交通规划,合理确定跨河桥梁间距提供了理论依据。

Study on accumulated effect of high density bridges on flood discharge of Shahe River

The construction of bridge group in urban river channel with flood control requirement changes the river regime, velocity and water level, and the superposition of backwater effect is significant, which will increase the flood control pressure on cities. Taking the section of Shahe River in the urban area of Luohe City, where high density bridges are built, as study area, the backwater effect on flood discharge under 9 cases of single bridge and 12 cases of multiple bridges are studied through the mathematical model. According to the calculated results, the curve of backwater height and length is drawn, the calculation formulas of backwater height in the upstream of single bridge and multiple bridges are fitted respectively. It provides theoretical basis for the formulating traffic plan of bridges crossing the river and determining the reasonable intervals among bridges.