Abstract
The erosive action of flowing water that removes boundary material from channel beds or banks around bridge foundations is known as scour. In gravel-bed rivers, the interaction of bridge piers and large heterogeneous gravel particles with the approaching flow can generate coherent turbulent structures in the flow.
The TRB National Cooperative Highway Research Program's NCHRP Research Report 1031: Determining Scour Depth Around Structures in Gravel-Bed Rivers provides state departments of transportation (DOTs) with new equations for predicting bridge pier scour depths for live bed and clear water scour in coarse-bedded rivers.