Use of synthetic ropes in deepwater moorings: ABS guidance notes

Synthetic ropes have many advantages in deepwater moorings, but their unique properties must be accounted for in the mooring system design process. For example, synthetic rope moorings rely primarily on rope elasticity for restoration forces, but the elasticity is nonlinear and changes with time. The ABS Guidance Notes on The Application of Synthetic Ropes for Offshore Mooring (1999) is developed mainly to assist the industry with standardized criteria covering all aspects of the use of these advanced materials for offshore moorings. The secondary purpose of these Guidance Notes is to highlight differences between the conventional steel components and their synthetic counterparts with regard to the influence of rope properties on the mooring system performance, and to provide practical guidelines on how to handle these differences during system design and installation. Sufficient details are provided in the Guidance Notes to determine properties through rope testing and to account for them in the mooring design process. To provide a comprehensive and an industry-wide acceptable standard, ABS formed an ad hoc committee consisting of operators, designers, rope manufacturers, fiber suppliers, installation contractors and governmental agencies to provide advisory comments to the Bureau on the development and future enhancement of these Guidance Notes.