Predicting Stress and Pressure at an Overfall

Abstract

Hydraulic shear stress and pressure forces have a major influence on the development and movement of a gully headcut or overfall. These forces were measured in a straight drop overfall model, and generalized prediction equations were developed using the dominant hydraulic and geometric parameters. The relatively simple models discussed herein provide a means of predicting the magnitude and variance of stress and pressure on the boundary of an overfall. Reasonable estimates of boundary shear stress allow estimation of headcut movement.