Performance of fiber-reinforced polymer-modified asphalt: Two-year review in Northern Arizona

This paper presents a 2-year review and an evaluation of the performance of fiber-reinforced polymer-modified asphalt concrete (FPMAC). A comparison is made of its characteristics with polymer-modified asphalt concrete (PMAC) through laboratory experiments and field observations. Polymers are believed to enhance the binding properties of the asphalt pavements to increase their engineering properties. Some researchers and highway agencies in the cold regions have considered adding fibers in the currently used polymer-modified asphalt concrete to produce FPMAC to be used in pavement construction. FPMAC has the potential to enhance asphalt pavement properties, such as increasing stiffness, resistance to deformation, and stability. An asphalt paving project made of PMAC and FPMAC was implemented in Flagstaff, Arizona, with a goal of evaluating the effect of fiber reinforcement in the performance enhancement of FPMAC. FPMAC and PMAC samples were collected at the job site and shipped back to the materials laboratories at both Northern Arizona University and Arizona State University for experimentations. Throughout the thermal cracking tests and dynamic modulus tests, all data indicated that FPMAC has better performance. After 2-year field visits, FPMAC has showed fewer cracks (with accumulative crack length of 11.2 ft) as compared with PMAC (with accumulative crack length of 123.2 ft). FPMAC has successfully demonstrated its abilities to resist thermal cracking, freeze-thaw cycling, and rutting deformation.