Flow Resistance of Riprap

Abstract

Flow‐resistance coefficients are essential in determining both water‐surface elevations and velocities that are used in many aspects of channel design. Channel boundaries requiring scour protection are often armored wifn riprap revetments that have roughness characteristics that differ from other channel boundaries. Resistance of flow over riprap boundaries is determined from flume data and is compared to the logarithmic and power‐law equations. Results show that the power‐law equation is applicable to intermediate scale roughness of riprapped surfaces. The logarithmic equation is applicable to small‐scale roughness with