INTERACTION OF STEEP WAVES WITH OFFSHORE STRUCTURES

Offshore structures having large diameter columns at the waterline cau se a significant disturbance to the ambient wave field, and large run- up around the columns. The paper discusses prediction of this effect i n regular sinusoidal waves and in focused wave groups characteristic o f extreme storm waves. Results are obtained from linear and second-ord er nonlinear analytical solutions for vertical circular cylinders. For very large waves, however, a fully nonlinear analysis is needed, whic h must be based on numerical discretization in both temporal and spati al dimensions. A finite-element procedure for predicting the interacti on of steep waves with offshore structures is briefly introduced.