Finite element analysis of flexible pipes: bending combined with tensile load

Abstract

The robustness and versatility of the flexible pipeline technology for the offshore oil industry were decisive for the achievement of consecutive records regarding the water depth. In some applications, this technology is the only available and suitable, but on the other hand, the prediction of the mechanical behavior of these structures when under bending is still a great challenge for design suitable, for example, to fatigue. Thus, this dissertation presents a new three-dimensional and non-linear FE model for local analysis of flexible pipes. This model, in addition to being able to represent all the tension armor wires and all the layers of the structure, allows not only the application of axisymmetric loads, but also bending moments. The effectiveness of the proposed model is corroborated by the satisfactory agreement of the numerical results with experimental measurements obtained through tests in which a flexible pipe sample is subjected to pure tension load and also combined tension with bending.