Abstract
Local scouring is a process whereby bed materials are removed around a marine structure due to the resultant disturbance of the uniform fluid flow. When not managed properly, scouring can result in a significant reduction in the stability of a foundation and a premature failure of an offshore structure. In this work, we proposed a hybrid numerical scour model which estimates the equilibrium scour depth around a structure by utilizing hydrodynamic turbulence models to obtain key flow parameters and an optimization function to predict the equilibrium scour depth. It was demonstrated that the evolution of the normalized Shields parameter could provide a pathway to obtain the equilibrium scour depth of a system within a limited number of iterations. Hence applying an optimisation function into the simulation model, it was shown that the estimated scour depth obtained from the simulation agreed reasonably well with experimental data. The simulation done in this work was performed in ANSYS-FLUENT. This paper provides a framework of utilizing hydrodynamic and an optimization algorithm to determine an equilibrium scour depth around an offshore structure. Moving forward, additional work is proposed in applying this model to different structural configurations to evaluate the robustness and reliability of such a model.