Investigation of Asphalt Concrete Layer Strains from Wide-Base Tires

The application of a continuum-based finite-layer mechanistic model to evaluate pavement strain response under moving traffic loading generated from wide-base tires is presented. The model incorporates important pavement response factors such as the noncircular contact area, complex contact stress distributions (normal and shear), vehicle speed, and viscoelastic material characterization. Results of a parametric study in which two typical thin and thick pavement sections were subjected to traffic loading moving at different speeds are included. The impact of vehicle speed on the strains induced in the asphalt concrete layer is consistent with the results from several field studies. The study reveals that especially in the case of thick pavements, the fatigue failure mechanism resulting from wide-base tires is different from those generated by conventional tires. With thick pavements longitudinal fatigue cracks are expected when wide-base tires are used.