Incipient Sediment Motion and Riprap Design

Abstract

The available information on incipient sediment motion criteria for both unidirectional and oscillating flow motions is summarized and analyzed according to the Shields diagram for incipient motion. The Shields diagram is extended for large and small particle sizes, on the basis of data collected in China. Design guides prepared by the U.S. Army Corps of Engineers and the California Department of Transportation are compatible with the extended Shields diagram for incipient motion.