Laboratory Study to Evaluate the In-Situ Use of Rejuvenator Seal Material to Restore In-Service Asphalt Pavement

Abstract

Rejuvenator seal material (RSM) is designed to revitalize an aged asphalt binder by spraying it on the surface of roads. It restores the mechanical properties of the existing pavement. This paper studied the effectiveness of RSMs containing cooking oil residue, motor oil residue, coal oil, solvent, and virgin or styrene-butadiene-styrene (SBS) modified 60/70 bitumen to improve the behavior of an in-service pavement. Three stages were followed to formulate RSMs. To achieve the effective oil, the penetration grade and softening point changes of rolling thin-film oven (RTFO) + pressure aging vessel (PAV) aged 60/70 bitumen mixing with different percentages of oils were studied. Then, the penetration depth of benzene, toluene, and xylene in hot mix asphalt (HMA) samples were measured to choose the most efficient solvent. Finally, the penetration depth of RSMs with various mixing ratios in HMA mixes was measured to determine the mix design and application values (g/m2). RSM-A (5% COR+5% MOR and 60/70 bitumen), RSM-B (5% COR+5% CO and 60/70 bitumen), and RSM-C (5%COR+5%CO and SBS modified 60/70 bitumen) were selected for further assessments. Other than the aforesaid RSMs, RejuvaSeal was used as a generic commercial substance. A British Pendulum Test was used to ensure sufficient skid resistance to reopen the traffic soon after distributing the RSMs. Dynamic shear rheometer and bending beam rheometer tests were used to investigate the rheological properties of extracted bitumen from the upper 1.5 cm layer of the pavement with and without RSMs. Moreover, the fatigue behavior of rejuvenated asphalt mixtures was studied by the 4-point bending test. Based on the results, all RSMs had a positive effect on the softening of the aged bitumen. All RSMs regained the fatigue performance of the aged binder. However, they showed the reverse effect on the rutting resistance. RSM-C containing 5% COR+5% CO and SBS modified 60/70 bitumen considerably modified the rheological properties of the aged binder even better than those mixtures rejuvenated by RejuvaSeal.