Simulation of water surface profile in vertically stratified rockfill dams

Detention rockfill dams are accounted as economically efficient structures for flood control, river bed and banks protection, flow diversion, etc. As the hydraulic behavior of these structures, when are used for flood control, is affected by the depth of water in their porous media, there is interests to predict water surface profile through the body of these structures. In this research, we developed a numerical model for prediction of the water surface profile in heterogeneous (stratified) detention rockfill dams. The new model is a modified form of gradually varied flow (GVF) equation which has been solved by direct step method and can also be applied to the flood routing. To validate the numerical model, a set of laboratory experiments has been conducted and the results were compared with those provided using the numerical model. As the maximum mean error is determined as 17.6%, it is found that the introduced model gives satisfactory results and it can be used to determine the water surface profile, and consequently, computing flood routing.