Influence of Soil-Structure Interaction on Fatigue Life of Offshore Structures

Offshore jacket structures are extensively used for exploration and exploitation of offshore hydrocarbons since seventies. These bottom fixed lattice structures are subjected to wave loading throughout its lifetime. Tubular joints are prone to high stress level and their fatigue life is decided by this. Offshore structural design codes such as API, DNV etc., have given the procedure for the fatigue life estimation based on the stress level predicted at local level. This procedure has been adopted to predict influence of soil structure interaction on fatigue life of jackets and the results are reported. The scope of numerical investigations extends to the influence of depth of fixity as well.