In this paper we consider the problem of fatigue damage arising on light alloy space frame tower subjected to wind induced vibrations during the service lifetime. In order to mitigate the fatigue damage, a passive control technique is proposed, based on the implementation of viscoelastic dampers. A full stochastic formulation is adopted for wind loading, vibration calculation and fatigue analysis. Among the many methods available in the literature for fatigue analysis, the Rayleigh method is selected for calculations. The obtained results show that aluminum lattice towers may be very sensitive to fatigue problem. A design procedure is then outlined that allows to assess the optimal damping ratio required in order to extend the structure service life up to target one; finally, two different design strategies are incestigated for sake of comparison.
On the Fatigue Optimization of Damped Space Frames under Stochastic Wind Excitation
APRILE, Alessandra;
2000
Abstract
In this paper we consider the problem of fatigue damage arising on light alloy space frame tower subjected to wind induced vibrations during the service lifetime. In order to mitigate the fatigue damage, a passive control technique is proposed, based on the implementation of viscoelastic dampers. A full stochastic formulation is adopted for wind loading, vibration calculation and fatigue analysis. Among the many methods available in the literature for fatigue analysis, the Rayleigh method is selected for calculations. The obtained results show that aluminum lattice towers may be very sensitive to fatigue problem. A design procedure is then outlined that allows to assess the optimal damping ratio required in order to extend the structure service life up to target one; finally, two different design strategies are incestigated for sake of comparison.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
