Sediment Transport Mechanism and Grain Size Distributions in Stony Bed Rivers S.FUKUOKA

The riverbed elevation of stony-bed rivers is controlled by boulders and cobbles. The authors have determined the mechanism of riverbed variation, characteristic grain size groups, and riverbed stability in stony-bed rivers from the results of field experiments on straight channels conducted in the Joganji River. In this study, we analyzed the results of field experiments using a meandering channel of the Joganji River. We examined characteristic grain-size distribution in meandering rivers with boulders and cobble and effects of meander and bank revetment on riverbed elevation and grain size distribution. Furthermore, we determined dimensionless physical parameter governing the forming of stable cross-sections in stony-bed rivers. 1