| Abstract: | This paper presents some findings of an investigation into the dynamic behaviour of offshore gravity platforms excited by waves. Results obtained from a finite element model are presented in the form of dynamic magnification factor curves for two structures typical of current concrete platform designs. In order to facilitate interpretation of these results a simple two degree of freedom model is developed and the equivalent results presented. These are found to be very similar to those obtained from the more detailed idealization, and it is therefore concluded that the principal mechanisms involved in the dynamic behaviour of offshore gravity structures are adequately represented in the simple model. Several useful insights into this behaviour are then achieved by closer examination of the two degree of freedom configuration. |
