Effect of Sodium Alginate Fibers Encapsulating Rejuvenators on the Self-Healing Capability and Cracking Resistance of Asphalt Mixtures

Abstract

In this study, the effect of adding sodium alginate fibers to enhance the self-healing capability of asphalt mixtures was evaluated. Two fiber types containing two different rejuvenators were synthesized, and their production parameters were optimized. A self-healing experiment was conducted using a three-point bending setup to evaluate the effect of different fiber contents on the healing efficiency and strength recovery of the mixtures. The fracture resistance of the mixtures at intermediate temperature was evaluated using the semicircular bending (SCB) test. Additionally, the rutting and fatigue behaviors of recovered binders were evaluated through rheological tests. The self-healing experiment showed that the asphalt mixture prepared with 15% fiber content by weight of the binder exhibited the best performance. From the SCB test, the highest critical-strain energy release rate (Jc) value was obtained at a 5% fiber content for both fiber types. Binder testing showed that binder blends with 5% fiber content had the highest rutting resistance. Linear Amplitude Sweep (LAS) test results also indicated that the binders with 5% fiber content exhibited the best performance against fatigue cracking. Overall, the use of 5% fiber seems to be a promising alternative and should be further evaluated.