In order to understand sediment transport process based on knowledge of their soil properties and hydrodynamic behaviour a series of 2D laboratory controlled small-scale experiments were conducted using the Ahlborn sediment mobile bed tank (4.0×0.6×0.2 m). Experiments were conducted in smooth and rough bed conditions with purposely-built Soil Protrusion Apparatus (SPA) to measure the basic parameters on which erosion depends. Sediment deposition patterns in equilibrium stage associated with different bed roughness and particle size distributions were fundamentally investigated. Extended physical modelling of crescent zones also includedudanalysing their grain size distribution. Dimensional analysis and multiple linear regression methods were employed to derive a simple empirical relationship for erosion rate (ER) in terms of the shear stress (τs), average grain diameter (d50) and soil protrusion (z) for smooth and rough sedimentudbed conditions. These analyses also suggest ways to refine empirical models, examining transport rates to explore the limits of erosion and deposition influences in shallow flow conditions.
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