Lateral Bed Load Transport on Side Slopes

Lateral bed load transport is studied in laboratory flume and wind tunnel. Introduction of laterally inclinable wind tunnel permits accurate measurements of shear stress on side slope and of lateral bed load. The result of wind tunnel test was examined by an open channel experiment. A universal formula for the lateral bed load q*_l is presented as a function of inclination of side slope, θ, and dimensionless shear stress τ*/τ*_c; and the expression is q*_l/tanθ = α(τ*/τ*_c)β. The numerical constants α and β are found to be 0.0039 and 1.5, respectively, for τ*/τ*_c > 1.07. The formula may add some information to bank protection engineering, prediction of river meander, and to widening of braided river.