Local Scour at Sloped-Wall Spur-Dike-Like Structures in Alluvial Rivers

Abstract

The effect of side slope on the prediction of the maximum local scour depth around sloped-wall spur-dike-like structures has been investigated using two existing prediction methods where slope factors were considered. The first one was developed from experimental data and is empirical in nature while the second one was developed using an analytical treatment by considering the flow concentration in the restricted region of scour hole. Both of the above approaches are applicable for clear-water scour. With the aid of the analytical model, the slope factors for the empirical formulas have been extrapolated for milder side slopes. The results of the above two methods together with the maximum measured local scour depth around a spur-dike-like structure in an alluvial river have been compared and discussed with particular emphasis on the effect of side slope on estimates of the maximum local scour depth.