Dynamic Push-Over Analysis of Fixed Offshore Platforms Under Metocean Loading

Document Type : Research Article



Basics of dynamic push-over analysis and static push-over are same. But in the dynamic case the wave or seismic loads are exerted to structure dynamically. With increasing intensity of dynamic loading in every step, structure would then be analyzed. Results of these two analyses are “push-over graphs” that show behavior of structure. Two platforms were selected for investigation. At first static push-over analysis and then dynamic push-over was performed for two platforms. Results of the two analyses were compared to each other. FEM based program “ABAQUS” was used for modeling. In this investigation, following results were found: Jackets behavior in both dynamic and static push-over analysis is same for linear range of jacket behavior; but in nonlinear range, results are different. In dynamic push-over analysis reserve strength of jacket structures was estimated to be higher than that of static push-over analysis. In dynamic push-over analysis ductility capacity was increased compared with static push-over and structure can bear more partial failure in comparison with static case.


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