Dynamic response of offshore platforms installed on sloping seabed under actual seismic loading

Document Type : Research Paper

Authors

Civil Engineering Department, Shahid Chamran University of Ahvaz, Ahvaz, Iran

Abstract

This research numerically investigates the structure behavior of steel jacket platform stand on 20 degrees inclined seabed and exposed to the earthquake. Considering the inclined seabed, the effect of the main variables on the structural behavior of the steel jacket platform subjected to the four famous earthquakes are discussed. The most effective variables of the structural response contain stresses and displacement. The stresses and displacement of the main four legs and as well as at the top of jacket structure will be as indicator for the structural response. ABAQUS 6.14 is used to model and analyze. The research finds that the change in the mass location will generate torsion effects which vary according to the leg's location and its length. In the sloping seabed it is necessary to use a stiffer tubular section to resist the torsional effect.

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