ABSTRACT
An experimental study was carried out in the framework of a researchproject concerning the development of a mathematical model for morphological computations in rivers in the case of non-uniform sediment. During two years (1979–1981) a series of laboratory experiments were carried out in a straight flume under steady, uniform (equilibrium) conditions with a restriction to bed-load transport and the dune regime. The flume was fed upstream by different mixtures of two very narrow sieved size fractions. The behaviour of these fractions was studied by extensive sampling of the bed (dunes). The overall results of the experiments (mean water depth, velocity, energy slope, dune height and mean probability of each fraction in the bed) were used to verify existing models for the transport per fraction, dune height and bed roughness.
