LIFE CYCLE ANALYSIS OF A GUYED MAST CONSIDERING GUST AND VORTEX EXCITATION

摘要

Frequent wind events are usually crucial for the fatigue of slender structures. In these events, the wind profiles often differ from the strong wind assumptions. Furthermore, for the dynamic analysis of guyed structures subjected to turbulent wind either quasi-steady models for the buffeting wind loads in the time domain or unsteady models in the frequency domain are available. Frequency domain models require a linearization of the structure's nonlinearities. Quasi-steady models lead to forces that correspond to measurements only in high winds. In this paper, time-domain models for unsteady buffeting wind loads and for vortex excitations are presented. A numerical analysis of a guyed mast subjected to turbulent wind is done considering buffeting and vortex excitation, where the shape of the wind profiles differs from common assumptions. The wind-induced loads are derived from numerically generated, turbulent wind fields, whose properties are verified with full-scale wind data. The results show a strong dependency of the stress resultants as well as the maximum lateral tip deflection on the shape of the wind profile.