Suspended Sediment Transport and Beach Profile Evolution

Abstract

A simplified analytic investigation of the local suspended sediment transport in the onshore‐offshore mode is performed, and is then adapted for computer solution to model beach profile evolution. The transport scheme involves both first order wave induced and mean “return flow” currents, coupled With an exponentially shaped sediment concentration profile. Five criteria for a “good” model are established, four of which are at least qualitatively satisfied by the present work. The model generates profiles of either the normal or storm types, depending on the wave conditions and sediment characteristics. The normal profiles are monotonic and concave upwards while the storm profiles contain one or more bars. The model responds to changes in water level due to tides, storm surge, or long‐term fluctuations, and the relative rates of profile evolution appear to be correct. More research is required before quantitative accuracy can be achieved.