Stress Cycle Assessment of Cables under Wind-Induced Vibrations: A General Probabilistic Approach

Abstract

A general numerical framework to estimate the stress range versus number of cycles curves experienced by a cable due to wind-induced vibrations is presented in this paper. The algorithm associated to the proposed numerical framework relies on a probabilistic approach to account for the uncertainties in the cable properties, initial conditions, damping, and wind excitation which are the variables that govern the wind-induced vibration phenomena in cables. Monte Carlo simulations and the concept of importance sampling techniques are used to propagate aforementioned uncertainties in which the latter is used to significantly reduce the computational costs when new scenarios with different probabilistic models for the uncertainties are evaluated. The proposed numerical framework also utilizes a high fidelity cable model that accounts for the helical geometry of cable components and is capable of capturing changes in cable curvature due to transverse vibrations. A 15 mm diameter high-strength steel strand under vortex shedding excitation mechanism is considered as an illustrative example to show the robustness and computational efficiency of the proposed numerical framework.