COMPARISON OF FATIGUE DATA FOR POLYESTER AND WIRE ROPES RELEVANT TO DEEPWATER MOORINGS

Polyester ropes are now established in deepwater moorings, but more research is needed to understand long-term durability and to optimise systems. Three categories of rope failures – environmental, surface damage, and structural – are not considered to be likely problems for deepwater polyester moorings which are properly designed and used. Fatigue of fibres in the rope is thus the concern of this paper. The fatigue mechanisms of interest are creep tensile fatigue, compression fatigue and internal abrasion. Laboratory test data on potential fibre fatigue mechanisms is reviewed with reference to typical mooring system service conditions. For a 20 year life