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Rubber compound aging is unavoidable. It changes material molecular structure and mechanical properties resulting in undesirable changes in tire performance. The behavior of aged tires was simulated using the finite element method after investigations regarding the boundary conditions, such as temperature, air composition and time of exposure, to reproduce in laboratory the aging observed in the market. During service life, the tire undergoes repeated and complex stress cycles resulting in heat generation by hysteresis. It is critical in regions like belt edges where temperature measurements show values up to 70°C for passenger car tires and more than 100°C for trucks. The inflated air permeates through the tire components leading to oxidative conditions propitious to fatigue and crack propagation. Aging is related to the tire operational conditions but engineers usually accelerate the process in lab tests by increasing the temperature, following the Arrhenius law.

This study concerns vibration phenomena induced by the passage of a vehicle in hold-down towers of monocable ropeways and by the chocks produced by the clip on the-sheaves-battery rollers. A dynamic model is developed for the “tower-sheaves battery-vehicle”system. This model takes into account the influence of the vehicle weight and inertia as well as the dynamic characteristics of a 16-rollers symmetric sheaves banery and those of the tower. In order to validate the model experimental data were obtained in industrial equipament. Their spectral structure were determined by two analysis mediods: the first one is based on Fourier transform while the other is a parametric hybrid method, the so called AR-CAP (Autoregressive-Capon) method that makes it possible the analysis in the time-frequency plane.