SCOUR AROUND BRIDGE PIERS IN STEEP STREAMS

Abstract

This paper describes the results of a laboratory investigation to determine local scour depths around bridges piers. The experiments were designed to simulate steel gravel rivers with slopes between 0.005 and 0.02 and Froude numbers in the range from 0.8 to 1.2. A widely graded sediment, typical of these rivers, was used and equilibrium sediment transport rates were imposed. Effects of shape and skewness of the bridge piers were considered. The observed depths of scour are compared with depths calculated using existing empirical methods, and a new correlation between skewness and shape is proposed.