Tension–torsion fatigue behaviour of wire ropes in offshore moorings

An earlier paper by the author discussed the behaviour of helically spun wire ropes when subject to axial load [Ridge, I.M.L., 2008. Torsional characterization of ropes used offshore. Journal of Strain Analysis 43(2), 121–139.]. The response of the rope varied, depending upon the rope's construction and whether the end of the rope was free to rotate or was fixed. This paper presents the results of an extensive research programme which highlight the practical implications of the torsional fatigue behaviour of ropes with especial reference to their use in offshore applications. The results are also relevant to a much broader range of rope applications where long lengths of rope are employed such as deep mine hoisting and reversible aerial cableways. The torque which may be generated in the various components used offshore may have serious effects in both handling and installation, as well as in the longer term service (fatigue) performance.