Numerical Simulation of Bridge Contraction Scouring at Abutments

With the increasing progress in computer calculation speed, the 3D simulation of flow together with sediment transport has become possible. In the present work 3D numerical modeling of flow pattern and scouring around bridge abutments is conducted. For this purpose the SSIIM model was utilized. In the first stage of calculation flow around an abutment on a non erodible bed was modeled and results were compared with the experimental data. The results showed a good agreement for the velocity field and water surface level. It was also concluded that the difference between the numerical results and experimental measurements increased as the abutment length or flow discharge or in another word flow disturbance and turbulence increased. The numerical model was then used for scour prediction around the abutment. Results showed a good agreement with experimental data for the location of the maximum scour depth. However, the scour depth was under predicted by 16%. The present study shows the validation and errors of such models for application in river engineering problems.