Author(s): Jenn Wei Er; Adrian Wing Keung Law
Linked Author(s): Jenn Wei Er
Keywords: Sediment transport Sediment disposal Sediment clump Predictive modelling Environmental
Abstract: The rapid expansion of coastal cities has increased the need for dredging and land reclamation to support maritime navigation and infrastructure. However, open-water disposal of dredged sediment raises environmental concerns, particularly regarding sediment placement precision and turbidity from suspended particles. A detailed understanding of near-field sediment dynamics is essential for effective engineering evaluations. Conventional models assume that dense sediment clusters are released instantaneously into the water, creating a vortex cloud that holds the particles together. This approach, however, does not fully account for finer sediments, which often form clumps. These clumps feature a fast-descending core surrounded by shedding sediment, increasing suspended sediment volume and environmental risks. Despite their significance, sediment clump dynamics are not well understood. This study presents a new mathematical model to describe sediment clump behavior, focusing on the rapid descent of the core and sediment shedding due to lee-side vortices. The shedding process, which influences the core's mass, is modeled using the Cloud Number – a dimensionless parameter governing sediment formation. Laboratory experiments validate the model, demonstrating its potential as a tool for improving sediment disposal strategies and reducing environmental impacts.
Year: 2025