Two scale numerical simulation of high value large diameter rope

Large diameter steel wire ropes are extensively used in subsea construction. Assurance of these ropes is critical for safe operations and well programmed maintenance / discard. However, service life is estimated by up scaling and extrapolating beyond proven theories on significantly smaller ropes, meaning scaling effects may be hidden. Given the limited experimental validation of large diameter ropes, this paper addresses upscaling validation through numerical simulation. Advancements in finite element analysis software related to beam-to-beam contact now make it possible to simulate the behaviour of wire bundles. Making use of this, the paper presents the development of a numerical model for multi-strand low rotation steel wire rope. The approach is a two-scale model. The global model represents the full rope with strands modelled as beam elements. The load distribution is calculated among these strands. The local model represents strands where individual wires are modelled by beam elements and, knowing the strand loading, it calculates the wire stresses. Cyclic reeling on a sheave is simulated to evaluate long-term rope performance.

Author(s): M. Martinez, R.B. Kante, P. Sicsic and D. Cannell