Author(s): Davide Motta; Ramon Pacheco; Riccardo Telo
Linked Author(s):
Keywords: Erosion models; Sediment transport; Turbulence; Interaction between water and structures; Scouring
Abstract: The evaluation of the maximum local scour depth around the piers of a bridge was here made through the numerical modelling on mobile bed, where incompressible threedimensional free-surface turbulent hydrodynamics was simulated through the CFD code (CFX-5). The water flow and shear stress fields, generated by the interaction between water and structures and described through the three-dimensional model, were coupled with the dynamics of the sediments, which was reproduced through a 3-D advection-dispersion numerical scheme as regards the transport in suspension, while the variation of bed elevation was calculated through an ad hoc morphologic model based on the application of the mass conservation equation, written along two dimensions. The results allowed characterizing both the dimensions of the scouring hole and the alternatives of solution for the control of the erosive process. The reliability of the mathematical modelling is conditioned to the possibility of calibration and verification of the scour model, which can be carried out on the basis of an in situ monitoring campaign which not suffers from scale effects.
Year: 2007