Experimental assessment of hot mixtures of asphalt concrete (HMAC) properties after the use of polyester fibers

Cracks are one of the principal distress mechanisms in asphalt pavements that substantially reducing their long term durability and service life. The use of substandard materials in production of Hot Mixtures of Asphalt Concrete (HMAC) affects the performance of asphalt pavement. Polyester fibers have been incorporated into HMAC to improve its resistance to cracking. Polyester fibers act as a three dimensional reinforcing network connects the components of HMAC together thus helping to reduce the occurrence of thermal and fatigue cracks under various climatic conditions and repeated loading. In this research, three different ratios of polyester fibers were selected (0.4, 0.5 and 0.6%). A total of forty eight (48) specimens were created and subsequently examined to evaluate optimum asphalt content (OAC) for the control mixture and three asphalt mixtures containing polyester fibers. Following the determination of OAC, twenty four (24) specimens were produced and tested to assess the behavior of polyester fibers and its impact on the characteristics of HMAC using the Marshall and indirect tensile strength tests. The laboratory results revealed that the addition of polyester fibers to HMAC improves the cracking resistance of the mixture by increasing its flexibility and ability to withstand repeated stresses and strains. The results further indicate that the mixtures incorporating polyester fibers exhibited higher values of ITS relative to the control mixture. Polyester fibers also showed potential sustainability benefits through improved pavement durability. The research results confirmed good agreement with the findings established in previous European studies on the polyester fibers asphalt mixtures. Finally, statistical analysis of data confirmed that the observed differences were significant and reliable.