Wave Run Up as Important Hydrodynamic Issue for Gravity Based Structures

Gravity Based Structures (GBS) are now seriously considered as LNG import terminal. When the environment of wind and waves is strongly directional, with an optimum orientation of the GBS a significant shielding can be achieved, reducing the weather downtime. However, the application of Gravity Based Structures also results in a number of hydrodynamic challenges, of which wave run-up is the subject of the present paper. Because of the optimized heading of the GBS beam to the dominant sea direction, typically the survival conditions will be beam to the GBS as well. This means that the wave run-up and possible green water on the deck of the GBS is a problem that needs serious evaluation. This run up problem is studied numerically with an improved Volume Of Fluid (iVOF) method. Results are presented concerning the generation and propagation of waves, the influence of deflectors, and the effect of wind.