Influence of Wave-in-Deck Forces on the Reliability Index of Jacket- Pile-Soil System

The steel jacket platforms were mainly designed in the 70s for the oil and gas explorations and productions in most offshore fields such as North-Sea. Due to lack of full knowledge about ,any design parameters and modern techniques in analysis of jacket-poil-soil systems. the variations in the seabed and also sea mean water level and subsidence in the sea bed, the initial aie-gap designs today might nit be sufficient to provide an accepted safety margin for the jacket-poil-soil system. In many cases, these jacket platforms are still in operation and may encounter extreme waves which exceed the deck height. Hence, the extreme waves approacbing the deck area may impart large forces on the jacket platform which also effect the overall safety of the system. The total forces induced by the wave stepping through jacket at each step can be computed through an integration aver whole structure and are superimposed by the forces on the deck and so the current induced forces. the direction of the waves on the dect areas and the current super-imposed forces on the wavws are considered. The other components such as current blokage and wave kinematics factors might also considered in wave calculation method.