Many flexible pavements constructed of normal hot-mix asphalt (HMA) are susceptible to functional failures before their design life mostly by the excessive traffic loads. It seems that there are, at least, two countermeasures dealing with the construction materials for mitigating this problem. The former is to reinforce the HMA pavement by polymer geosynthetic reinforcement. The latter is to improve the pavement material by using polymer-modified asphalt (PMA). A number of experimental studies have been individually performed looking for effects of reinforcement on reduction of pavement settlement alone and for performances improved by using PMA alone. However, little is known on the behaviours of PMA pavement reinforced with polymer reinforcement. In this study, a series of laboratory physical model tests were performed on PMA pavements either unreinforced or reinforced with different types of polymer geosynthetic reinforcements. Then, vertical stress was cyclically applied on the pavement surface by means of a footing. It was found that: i) the residual settlement of the footing significantly decreased with PMA pavement reinforced with geosynthetic reinforcements; ii) the maximum shear strain in the soil layer supporting the pavement was significantly less developed and less localised with reinforced PMA pavement than the unreinforced pavement; and iii) using a geosynthetic reinforcement that had more contact area with pavement bottom resulted in much better performance.
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