Effect of surface reinforcing agent on road use and permeability performance of porous asphalt pavement

To address the frequent raveling issues of porous asphalt pavement, an indoor test was conducted on a maintenance material—oily diluted asphalt reinforcing agent—to determine the effect and optimal dosage of the pavement reinforcing agent. Results provided a technical path to avoid scattering issues of porous asphalt pavement.

PA-13 asphalt mixture was obtained from the construction site, and six groups of Marshall and rutting plate specimens were prepared. The standard dosage of the preset reinforcing agent was 1 kg/m², which was calculated based on the area of the Marshall and rutting plate specimens. The six groups of Marshall and rutting plate specimens were smeared according to the preset standard dosages of 0%, 60%, 80%, 100%, 120%, and 140%. Asphalt mixture density, water immersion raveling, permeability, British pendulum number (BPN), and texture depth (TD) tests were performed to study the effects of the reinforcing agent on the void ratio and antiraveling, permeability, and antiskid performances of porous asphalt pavement.

First, when the dosage of the pavement reinforcing agent was 80%–100%, the antiraveling performance of the pavement material considerably improved. When the dosage of the reinforcing agent was 80%, the raveling loss rate was reduced by 7.49%, and the antiraveling performance was increased by 57.97%. When the dosage of the reinforcing agent was 100%, the raveling loss rate was reduced by 11.22%, and the raveling performance was increased by 62.96%. After the dosage of the reinforcing agent exceeded 100%, the antiraveling performance of the pavement material does not notably change. Second, the reinforcing agent blocked the void of the pavement surface layer, and the connected void ratio decreased by 4.0%–6.6% when the reinforcing agent dosage was 60%–140%. Third, reinforcing agents negatively affected the antiskid properties and water permeability of the pavement. When the dosage of the reinforcing agent was 100%, the BPN, TD, and permeability coefficient were reduced by 16.61%, 22.81%, and 28.66%, respectively, and the water permeability coefficient was much lower than the specified 4 500 mL·min⁻¹.

After comprehensively analyzing the effect of the reinforcing agent on the performance of the pavement, the optimal dosage of the reinforcing agent was 0.6–0.8 kg/m². When the dosage of the reinforcing agent was 0.8 kg/m², the antiraveling performance was increased by 57.97%, and the connected void ratio, permeability coefficient, BPN, and TD were reduced by 4.14%, 18.70%, 13.49%, and 25.14%, respectively.