Ricerc@Sapienza

In 1997, in front of the Pescara Harbour (Italy), a detached breakwater was constructed. In the successive years, the sediment transport due to the combined action of waves and coastal currents, in the area between the detached breakwater and the entrance of the Pescara Harbour, produced an accumulation of about 40,000 m3 of sediment per year. In this paper, the causes of the accretion of the bottom elevation in front of the Pescara Harbour entrance and the eects produced by the existing detached breakwater are investigated.

In this paper, the shoreline and bottom modifications produced by the presence of a T-head groin are simulated. We present a model for the bottom-change simulation, composed by two sub-models: a two-dimensional phase-resolving model for the simulation of the variation of the fluid dynamic variables inside the wave period and that takes into account the undertow; a second morphodynamic sub-model for the simulation of the bottom changes, in which the suspended sediment concentration is calculated by means of the wave-averaged advection-diffusion equation.

In this paper, we simulate the sea bottom modifications produced by the presence of a T-head groin. We present a simulation model of sea bottom modifications composed of two sub-models: a two-dimensional phase-resolving model that simulate the variation of the fluid dynamic variables inside the wave; a second sub-model to simulate the sea bottom modifications, in which the suspended sediment concentration is calculated by the wave-averaged advection-diffusion equation. The fluid motion equation and the concentration equation are expressed in a new contravariant formulation.

This work is inspired by the sudden resurgence of the submersed aquatic vegetation (SAV) bed in the Chesapeake Bay (USA). Because the SAV bed occurs at the mouth of the Bay's main tributary (Susquehanna River), it plays a significant role in modulating sediment and nutrient inputs from the Susquehanna to the Bay. Previous model studies on the impact of submersed aquatic vegetation on the development of river mouth bars lacked a complete mechanistic understanding.