Self-Healing Characteristics of Polyvinyl Alcohol-Fiber-Reinforced Hot Mix Asphalt for Enhanced Pavement Durability

Abstract

Pavement maintenance presents significant financial challenges, driving researchers to explore innovative approaches that can prolong pavement service life and reduce costly interventions. The objective of this research is to examine the feasibility of utilizing polyvinyl alcohol (PVA) fibers to self-heal asphalt pavements. A comprehensive mechanical testing strategy was developed to evaluate the self-healing capability of several hot mix asphalt (HMA) mixtures at the micro- and macro-level. Moreover, to assess the healing behavior of macro fractures in PVA-fiber-reinforced HMA, semi-circular bending (SCB) specimens were loaded until peak load and then allowed to heal at varying time intervals and temperatures for several loading cycles. Healing indices developed based on SCB stiffness, strength, and beam fatigue technique were utilized to measure the self-healing ability of control and reinforced mixtures. By comparing different concentrations of PVA fibers with a control HMA, the optimal fiber dosage was determined based on newly developed healing indices. This study also investigated the impact of healing time and different temperatures on healing. The results demonstrated that PVA fibers expedited the healing process, effectively healing macro-, meso-, and micro-cracks. The most effective recovery occurred with 0.3% fiber content at 40°C for a 2 h duration. Incorporating PVA fibers into asphalt pavements presents a promising solution for extending pavement service life and can be helpful in reducing maintenance costs.