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

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.