Journal of Basic and Applied Research International

This study investigates the influence of silt-laden flow on bed load transport and frictional resistance in an alluvial channel. A series of controlled experiments were carried out in a 13m long tilting flume using uniform gravel (1.9 mm) as bed material and fine silt (0.062 mm) as wash load. The tests covered a wide range of silt concentrations, from approximately 97 ppm to 9165 ppm. The results indicate that bed load transport rate increased by nearly 65% with rising silt concentration primarily due to a reduction in friction factor. A comparison with existing bed load transport equations, including those by Meyer-Peter and Müller, Misri et al., and Khullar, shows that conventional models tend to overestimate transport rates under silt-laden conditions. Friction factor calculations further reveal a systematic decline with increasing silt concentration, contradicting the criteria proposed by Arora et al. but aligning with Khullar’s predictive model. In addition, silt infiltration into the gravel bed was found to reach approximately 50 times the mean gravel size, with the highest accumulation occurring near the surface in upstream sections. These provide valuable insights for improving sediment transport modelling, river ecosystem management, and hydraulic engineering applications in silt-prone environments. Moreover, the insights gained from this study can serve as a foundation for future research aimed at refining sediment transport models and developing effective management strategies for silt-laden river systems.