A parametric investigation of wind-induced cable fatigue

Abstract

This paper presents a parametric investigation of the axial fatigue performance of suspended cables subjected to lateral wind-induced vibrations. An up-to-date literature review of cable fatigue is followed by numerical analysis of the total axial fatigue damage produced by different out-of-plane wind excitations on cables with different initial sags. The fatigue damage is calculated in the time domain through an adequate cycles counting method. A discussion of the influence of the Irvine parameter on the total fatigue damage is then performed. The results may be adopted to compare the risk of fatigue ruptures occurring in suspended cables (such as transmission power lines) with different Irvine parameters. The numerical simulations are conducted using a tridimensional geometric nonlinear finite element model, experimentally validated in previous works. The turbulent wind field is simulated as a multivariate mono-dimensional Gaussian process. The investigation first explores the case of uncorrelated nodal drag forces and it is then extended to statistically correlated ones. A stochastic analysis of the cable responses under different wind loads is also proposed to discuss the hypothesis of Gaussian distribution.