Numerical procedure for the analysis of damaged polyester ropes

In this paper, a numerical model capable of representing the impact of damage on the overall response of jacketed polyester (PET) ropes is presented. This model considers rope behavior under axisymmetric loading conditions and can account for the degradation of rope properties, including the effect of broken rope components, on overall rope response. To consider the confinement effect of rope jacketing on interior rope components, the rope jacket is assumed to behave like a thin-walled tube. If a rope has broken rope components, the rope analysis is linearized by discretizing the rope into a series of two-noded axial-torsional elements. The formulation of these elements accounts for material and geometric nonlinearities. Results of numerical simulations are provided to show how changes in the L/dL/d ratio (rope length/rope diameter) and the initial state of rope damage influence the capacity, failure strain and stiffness of a damaged PET rope. Experimental data are used to validate the proposed model.