Bend stiffener are conical structures used in flexible riser systems in order to ensure smooth stiffness transition between riser and floating units, preventing excessive curvatures and protecting from failure. Made in polyurethane, the vast majority of analysis of bend stiffener-riser systems generally assume the material behavior as linear elastic or hyperelastic; time dependence, creep or stress relaxation are not considered. This work presents a parametric structural study of bend stiffeners, considering linear elastic and linear viscoelastic behavior using fourth order Prony series considering the temperature dependence on relaxation times. Different subroutines in FORTRAN based in UMAT -ABAQUS methodology are developed in order to calculate the mechanical response of bend stiffeners (deflection and curvature), assuming homogeneity, symmetry and isotropy. Case studies using solid finite elements made for different geometrical and material models and finally were compared with other works from different authors.

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