ABSTRACT
For more than a century, check dams have been used for stabilizing stream beds in mountain areas of Europe and Japan. Engineer and researchers have mainly been concerned by foundation scouring, spillway hydraulic capacity and equilibrium slopes. These works aimed to identify design criteria. Actually little is known about in which extend check dams influence the solid discharge in a given stream. Small scale experiments were undertaken to study their influence on the peak solid discharge and the transported volumes. A nearly 12% steep flume was used, with and without check dams. The analysis was performed in constant feeding conditions leading to dynamic equilibrium in each set up. The outlet solid discharges and the vertical evolutions of the bed profile were measured and analyzed in term of quantity and frequencies. We observed that grade control structures do not systematically induce a decrease in mean slopes; however, by segmenting the streambed, they strongly impact the bed level fluctuations and reduce bedload pulses’ volume.
