This work presents an analytical model for the structural analysis of flexible risers subjected to combined loads of bending, twisting and tension, as well as internal and external pressures applied to the riser. The proposed formulation, which comprises equilibrium conditions, constitutive equations and geometrical relations, leads to the solution of the problem in terms of the loads supported by the layers and deformation components of a flexible riser subjected to the above mentioned combined loads. All the modeling hypotheses are highlighted in the work. Comparisons between analytical results using the full-slip model and experimental results obtained in literature are shown and discussed. Some proposals leading to improvement of the presented model are drawn in the conclusions.

Issue Section:
Technical Papers
Keywords:
flexible structures, offshore installations, load distribution, deformation, bending
Topics:
Armor, Deformation, Flexible risers, Pipes, Stiffness, Stress, External pressure, Pipeline risers, Risers (Casting), Pressure
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 by ASME
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