Dynamic Analysis of a Guyed Mast with Uncertainties on the Guy Initial Tension and the Wind Load

Abstract

The dynamic response of a guyed mast is analyzed under wind load action. The structural model consists of a beam-column model accounting for the second order effect due to axial loads and one guy. The guy is represented by an extensible cable governed by nonlinear equations. The wind velocity is derived considering temporal and spatial correlations. The resulting governing system is discretized using finite elements and a reduced order model is afterwards developed using normal modes as a basis. The wind load is obtained from a stochastic wind velocity field and derived using the Spectral Representation Method. Usually, the design tension changes during the structure service life affecting the system performance. As the guy pretension is a significant parameter in the behavior of guyed structures, its variation is a relevant issue. Then, an uncertainty quantification appears necessary to obtain more realistic results. Since the nonlinear structures shows special sensitivity to the load, the mean value of wind velocity (used to construct the wind loads), is also considered as a stochastic parameter.