The Scour Bridge Simulation around a Cylindrical Pier Using Flow-3D

Abstract

Scour simulation is a way to prevent a bridge against the possible major damages. In this study, local scouring around a cylindrical pier in non-cohesive bed sediment was simulated with the aid of Flow-3D model capabilities. A rectangular channel with 0.4 m width and 1.0 m length and a vertical cylindrical pier with diameter of 0.03 m and height of 0.3 m were specified for simulation of scour depth. Simulations were performed at different flow rates of 5, 10, 19 and 30 L/sec., separately and parameters of flow velocity, fluid depth, Froude number, packed sediment height and changes in net sediment motion were investigated. According to the results obtained from the simulations and after 600 sec., maximum scour depths for different inflow rates were equal to 0.0, 1.3, 2.4 and 3.6 cm for 5, 10, 19 and 30 L/sec., respectively. It was also observed that the scour depth was comparatively higher in upstream while it was lower in downstream part of the pier. Comparisons between the simulated and observed scour depths, however, showed underestimates of 30% to 20% for upper and lower parts of the pier, respectively.