An Experimental Investigation of Bridgeflow II Kerb Channel Units

The results of an experimental investigation of kerbside bridge deck drainage units are presented. The conveyance capacity, resistance coefficients and sediment transporting efficiencies of different types of drainage unit used in shallow bridge drainage decks are examined over a range of bed gradients likely to be encountered in practice. The use of a V-shaped cross section is shown to be particularly effective in transporting sand and gravel material along the channel, and sediment threshold equations are presented. The overall hydraulic resistance of kerbside drainage units, together with the effect of joints and rib roughness on the walls of some other types of unit, is also illustrated.