This study aims to investigate different sediment particle sizes subject to transport characteristics of bed-load and suspendedload caused by nonlinear interactions of wave-tide-river in a tidal-estuary. A two-dimensional hydrodynamic coupling to a morphological model is developed to study this issue. A case study of Lanyang River estuary in Taiwan is applied and analyzed. The models are verified against field data (i.e., hydrodynamics and morphological change) collected from Lanyang River estuary during the invasion of typhoon Saola in July, 2012. Fairly good agreements are given comparing to field data. In general, the simulation indicates that suspended load could be transported toward offshore up to water depth of an order of approximately 10-15 m); it is not a major factor to affect morphological changes. The bed-load transport driven by the flood due to typhoon event is proven to be a major contribution to topographic changes in estuary. The presented results found that the erosion and siltation are both observed in the alongshore regions. In the estuary siltation of approximately 3-4 m on the north and south sides of the estuary and erosion of approximately 2-3 m are found respectively.

Included in

Engineering Commons