Abstract:

In mechanistic-empirical methods used in the design of flexible pavements, the mechanical responses of the cross-section under traffic load and environmental influences are determined and these values are converted into pavement life values with empirical transfer equations. The two main types of distress considered in empirical models recommended by different organizations are fatigue and rutting. According to these two distress types, there are many pavement life models proposed in the literature and these models contain significantly different coefficients. Even in the analyzes made with the same institution's fatigue and rutting models, the pavement life values differ significantly from each other. In this study, pavement life analyzes were performed with different empirical models for a traditional pavement cross-section. Transfer equations are compared with each other depending on the changing stiffness and thickness ratios of the surface and base layer. The results obtained show that the pavement life values calculated with rutting models for all organizations are higher than the values calculated with fatigue models. If the base layer stiffness decreases compared to the surface layer stiffness, the results obtained from different models converge. In case the surface layer thickness increases compared to the base layer thickness, it is determined that the models give significantly different results from each other.

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