Etude numérique sur les courbes de remous sous un pont à arcs.

Abstract

Bridges crossing floodplains may require special attention if they cause severe flow contraction and expansion which causes changes in water level and backwater type. The objective of this Master is to study, using HEC RAS software, the shape of backwater curves under an arch bridge. This work is divided into two parts, the first part is bibliographical research on free surface flows and its characteristics also the definition of backwater curve. In the second part, a simulation is performed by Hec-Ras. It is concluded from this simulation and this study that the bridge caused a loss of energy that decreased the water height, which changes the type of backwater upstream and under the bridge. Modeling of such cases requires the precise evaluation of four parameters: The length of expansion: Le, the length of contraction: Lc, coefficient of expansion: Ce, coefficient of contraction: Cc.