THE EFFECTS OF AGE ON THE STIFFNESS PROPERTIES OF A SUV TYRE

The pneumatic tyre is a difficult component to model accurately in all natural vehicle environments. Proposed tyre models should be validated with real test data collected on the specific tyre being modelled under the specified application conditions. The rubber in a tyre oxidises with the oxygen in the air used to inflate it as well as the oxygen in the air surrounding it. The effects of a tyre‘s age on the performance characteristics of a tyre such as vertical, longitudinal and lateral stiffness, are not well researched. In this study, the effects of a tyre’s age on stiffness parameters were determined. A tyre was artifically aged and tested periodically during the aging process. Simplified methods of quantifying the age of the tyre were investigated and used to update a validated FTire model. The results indicate that the vertical and longitudinal stiffnesses of the tyre have convincing dependencies on the age of the tyre. The use of the Shore A hardness of the tyre tread to update the FTire model was found to have good potential in accounting for the age of the tyre