2019 CSCE Annual Conference - Laval (Greater Montreal) Conference
Dr. Ram Balachandar, University of Windsor
Based on a series of hydraulic experiments conducted at the Sedimentation and Scour Study Laboratory at the University of Windsor, the effect of relative bed coarseness and blockage ratio on local scour around bridge abutments are presented. Scour around semi-circular bridge abutments with different diameters are compared under identical flow conditions for several blockage ratios. An analysis of blockage for different abutment is used to provide a clearer understanding on the impacts of relative bed coarseness and blockage ratio on local scour profile and maximum scour depth. Results of this study indicate that both equilibrium scour depth and scour profile are affected by blockage ratio. Clear differences can be noted in the scour geometry even for small changes in blockage ratio. With the increase of relative bed coarseness, the scour width and scour depth decrease correspondingly. Additionally, the approach flow depth shows a strong influence on the scour geometry. The study provides additional support for considering relative bed coarseness and blockage ratio in local scour prediction around bridge foundations.