Impact of Wide-Base Tire on Flexible Pavement Responses: Coupling Effects of Multiaxle and Dynamic Loading

Wide-base tires (WBTs) have been gradually adopted for trucks to improve fuel economy and driving comfort. This study aims to investigate the impact of WBTs on flexible pavement responses as compared to dual tires (DTs) coupling the effects of multiaxle and dynamic loading. A semi-analytical finite element model (SAFEM) was developed to simulate pavement responses under dynamic moving loads with high efficiency and good accuracy. The model was validated by comparing simulation results with field measurements from the instrumented section in the Long-Term Pavement Performance (LTPP) database. The influence of tire type, axle configuration, and pavement roughness was analyzed in terms of four critical pavement responses: longitudinal tensile strain at the bottom of asphalt layer, transverse tensile strain on pavement surface, near-surface shear strain, and compressive strain at the top of subgrade. The analysis results show that pavement responses induced by dynamic loads conform to normal distribution, and the variation of pavement responses increases linearly with that of dynamic loads. WBTs cause greater pavement damage than DTs in general. Among four pavement distresses, the highest damage ratio is observed for top-down cracking and the least one is for near-surface rutting. The damage ratios vary with axle configuration or speed rather than pavement surface roughness, especially for top-down cracking. The study emphasizes the impact of pavement roughness, tire type, and axle configuration on pavement responses.