Numerical analysis of buckling failure in flexible pipe armor wires

Abstract

Flexible pipes may be exposed to high axial compression and bending during deep-water installation. As the compression force is mainly sustained by the tensile armor layers, this may result in localized lateral or radial buckling failure in these layers. In this paper, a finite element model was created to evaluate the critical instability load of tensile armor wires under external pressure and compression. The tensile armor wires are modeled by curved beam elements under loxodromic assumptions. Other layers׳ contribution was simplified by spring elements and equivalent beams. The buckling load capacity and associated failure modes are obtained. The results are also compared with the results based on 3D Euler beam elements and results published in the literature. Parametric analyses were further included with respect to external pressure, friction modeling and the influence of initial imperfections.