顺溪拱坝溢流消能布置模型试验研究

Study of model test on overflow energy dissipation layout of Shunxi arch dam

顺溪拱坝为抛物线型常态混凝土双曲变厚拱坝,针对其水头落差大所带来的坝下消能防冲问题,对原设计方案进行改进。原设计方案表孔水舌直接砸击下游左侧护坡及河道底,且水舌落地后向四周折射,不仅对设计护坡的稳定性构成危险,而且势必威胁坝肩的稳定。通过水工模型试验方案比较,优化了溢流堰的平面布置和中孔出口体型,推荐了二道坝方案,改善了溢流堰进口及坝下水流流态,明显减轻了水流对坝下河床的冲刷,为设计提供了技术依据,成果可供类似工程参考。

Shunxi arch dam is a normal hyperbolic thickening concrete arch dam with high water head and serious energy dissipation problem.In the original design scheme,the water-jets coming out of the surface hole directly strikes the left slope and river bottom in the downstream of the dam and all-round refraction occurs.It threatens the stability of designed slope and the abutment.Through comparison of different schemes by hydraulic model test,we optimize the layout of the overflow weir horizontal location and the exit shape of middle hole,and recommend the subsidiary dam proposals.It improves the flow pattern of imports and downstream of the dam,and significantly reduces water erosion of the river bed.The results provide a technical basis for the design process.