Three-dimensional dynamic response of guyed towers to wind turbulence

Abstract

The three-dimensional dynamic response of a guyed tower subjected to turbulent buffeting was investigated analytically in this study. Nonlinear dynamic response was determined in the time domain using Newmark's method to perform a step-by-step integration of the governing equations of motion. A simulated windstorm containing both alongwind and acrosswind turbulences was generated using a second-order autoregressive process. It was found that the fluctuating response in the acrosswind direction was similar in magnitude to that in the alongwind direction, with the relative size of the alongwind and acrosswind components depending on wind direction. Resultant bending moments in the mast were increased significantly by the acrosswind motion, leading to larger peak leg loads. Peak mast displacements and shear forces, on the other hand, appeared to be less sensitive. Dynamic guy fluctuations and axial forces in the mast were also investigated.Key words: guyed tower, dynamic response, wind loading, wind simulation, structural analysis, finite element analysis.