Mechanical Properties of Porous Asphalt Concrete with Rejuvenators

Preventive maintenance using rejuvenators to extend the service life of porous asphalt pavements has been investigated recently in the Netherlands. Three rejuvenators (one bituminous binder and two emulsions) were applied in two test sections on motorways. In this paper the mechanical properties of porous asphalt concrete with rejuvenators are investigated using a three-point bending test combined with finite element (FE) modeling. Nano Computed Tomography (CT) is used to scan the internal microstructure of porous asphalt cores to research the distribution of the rejuvenators. The bending stiffness is determined by using a surface-up (rejuvenated area is located at the top of the beam) and a surface-down (rejuvenated area is at the bottom of the beam) mode to investigate the increased flexibility of porous asphalt concrete with rejuvenators. Two dimensional FE models of a single-layer porous asphalt (SLPA) beam and a two-layer porous asphalt (TLPA) beam are used to analyze the experimental data. The results of the investigation indicate that rejuvenators not only soften the aged mortar but also supply extra bonding within the porous asphalt concrete. The bending stiffness of the porous asphalt beam increased when rejuvenators were applied.