Nonlinear dynamic behaviour of jack-up platforms

Abstract Jack-up platforms may, under extreme wave loading conditions, exhibit significant nonlinear behaviour. This must be accounted for in the design of such platforms, in order to ensure satisfactory structural safety. In this paper an overview of the different sources of nonlinear platform behaviour is presented. Furthermore, it is outlined how those nonlinear effects may be modelled and handled in numerical simulation studies of structural response, with a special focus on the estimation of extreme response and dynamic amplification factors. Finally, it is discussed how nonlinear dynamic response may be accounted for in the design of jack-up platforms. The discussions and outlines are illustrated by examples from numerical simulation studies of jack-up behaviour.