Numerical Modeling as a Design Tool for Coastal Structures

Abstract

Coastal structures constructed on sediments are designed against storms. A comprehensive design of a coastal structure will require the integration of numerical models for coastal hydrodynamics, structures and sediments. Numerical models for predicting tides, storm surge and wind waves have improved significantly over the past 30 years. Relative sea level rise may accelerate due to the greenhouse effect but cannot be predicted accurately at present. The capabilities for predicting damage to coastal structures have improved considerably for the last 20 years owing to the improved laboratory experimental capabilities followed by the development of numerical hydrodynamic models. The quantitative understanding of the various components involved in cross-shore and alongshore sand transport has also improved due to the improved understanding of hydrodynamic forcing mechanisms and the significant efforts in collecting field and laboratory data on nearshore morphological changes and suspended sediment. However, it is still not possible to predict the long-term cycle of beach erosion and recovery caused by sequences of storms. In short, numerical models have been successful for the coastal problems which are governed by the conservation equations for mass, momentum and energy for water. The future progress for coastal sediments and rubble mound structures may be made innovative technologies coupled with improved physical insights gained from numerical hydrodynamic models. The integration of the numerical models will become essential for the life cycle and performance-based design of coastal structures.