Nonlinear random vibrations of a suspended cable under wind loading

Nonlinear random vibrations of a suspended cable under transversal wind loading, described by a constant term and a fluctuating component, are dealt with. A mechanical model, fully accounting for geometrical nonlinearities inherent in cable behaviour, is adopted. In view of the large size of cable structures, wind turbulence is modeled as a one-variate bi-dimensional random field. A Monte Carlo-based analysis is carried out by employing a very efficient technique for digital simulation of wind velocity fluctuation. This procedure is based on the spectral decomposition of the cross-power spectral density function (PSD) and the consequent representation of the turbulence field as a summation of fully coherent independent stochastic fields. The use of the aforementioned technique in conjunction with Galerkin’s method allows considerable computational savings in the evaluation of cable response, mainly related to the physical meaning of the eigen-properties of the cross- PSD.