Comparative analysis of pavement performance characteristics of flexible, semi-flexible and rigid pavement based on accelerated pavement tester

This study aimed to investigate the rutting and strain characteristics of flexible, semi-flexible (SF) and rigid pavement under the same accelerated loading condition. Specifically, flexible pavement was rubberized asphalt rejuvenated reclaimed asphalt pavement (RAP) pavement (RARR), semi-flexible pavement consisted of StyreneButadiene-Styrene modified porous asphalt concrete (SBS-PAC) and cement-based modified grouting material, while rigid pavement was polyurethane (PU) mixtures. An indoor test field was constructed and accelerated pavement tester (APT) was employed to apply continuous wheel loads. Twelve embedded fiber grating strain sensors were placed at the bottom of the surface layer with four in under each type of pavement. In total, 600,000 wheel passes were applied. Results revealed that no rutting hump was discovered for RARR while it was not until the completion of 150,000 wheel passes that PU and SF pavement saw evident rutting humps. As total rutting depth and rutting area increased, the fact that hump depth ratio decreased while hump area ratio increased indicated that rutting humps tended to spread outwards. When it came to maximum micro-strain underneath the pavement layer, it was found that with increasing number of accumulated wheel passes, RARR pavement presented the largest transverse micro-strain while SF pavement presented the largest longitudinal strain. Correlation analyses indicated that maximum micro-strain was in good exponential correlation with maximum rutting depth for RARR, SF and PU pavement. Finally, SF pavement presented the best PCI among the three pavements while PU pavement presented the worst, mainly because of its poor rutting resistance.