Movement of loose, sandy detritus by shallow water flows: An experimental study

摘要: Abstract Interactions between flowing water and natural, loose, sandy detritus, containing small amounts of clay, silt pebbles, were studies in flumes, using discharges over a large range slopes. These formed part general investigation particle transport by rivers, overland flows, rain-impacted, shallow flows. All flows strong enough to move the full size bed material supercritical channel systems always replaced initial sheet after sediment movement commenced. Even millimetre deep, behaviourally distinct suspended, saltation, contact loads existed. Suspended load was entrained throughout flowswept area, wherever suitable particles exposed. Saltation load, contrast, transportational capacity upstream few centimetres and, downstream, any new entrainment balanced deposition. Interaction saltatory flow largely controlled formation, geometry, transportation suspended loads. As vigour increased, saltation underwent series changes nature, most marked being from individual trajectories migration as ballistic dispersions (rheologic logic layers) which when interparticle collisions became common. reflected both qualitatively observed features rates, so that, terms results could be divided into discrete “fields interaction” on discharge-versus-slope plots. Transport rate increased rapidly with slope if grains moved trajectories. However, at bed-load concentration about 0.25% volume, rheologic layer thereafter, less strongly slope, closely following stream-power law. Below slopes 0.01 rills transported little sand but, through 0.01–0.04, transporting power greatly enormous 0.3. Concentration channels gave small, considerable pebbles. Although processes channels, general, paralleled those repetitive sedimentary structures contrasted markedly deeper, subcritical