Dynamic stress prediction in catenary wires for fatigue analysis

Abstract

Fatigue cracks in the contact wire are a possible cause of fracture which can induce huge costs. Fatigue study is thus of a great interest but requires an accurate computations of stress distributions. OSCAR is a SNCF software used to study coupled pantograph / catenary dynamics. It is based on Euler-Bernoulli beam meshes. This formalism is accurate to study the catenary displacements, but is not sufficient to compute multi-axial stresses, in particular in parts that can concentrate stresses such as the junction claws. This paper details and illustrates the strategy developed to compute a full multi-axial transient stress field, in any point of the contact wire. The dynamic displacement computed by OSCAR is expanded and combined with a precise nonlinear static state of a mixed model of beams and volume elements.