Scour depth prediction at the base of longitudinal walls: a combined experimental, numerical, and field study

Abstract

A series of small- and large-scale experiments and numerical simulations were carried out to produce datasets for maximum scour depth at the base of longitudinal structures. The small-scale experimental datasets were employed to develop an empirical relationship for predicting maximum local scour depth. The measured datasets for scour patterns and depths were used to validate the accuracy of our morphodynamics model, the Virtual Flow Simulator (VFS-Geophysics). The large-scale experimental measurements and numerical simulations lead to the development of another empirical relationship to estimate the maximum general scour depth near the longitudinal structures in large-scale meandering streams/rivers. The premise of this study is that the maximum scour depths obtained from the two equations can be used independently to represent local and general scour at the base of longitudinal walls in meandering rivers. However, for a more conservative prediction, the two can be linearly summed up to obtain a total maximum scour depth. The presented correlations illustrate regression goodness of r2 = 0.63 and 0.82 for the maximum local and general scour depth equations, respectively. Nonetheless, the developed equations are valid within a specific range of parameter for the sediment material, flow field, and waterway characteristics.