Experimental Study of Permeability Characteristic of Porous Asphalt Mixtures During Clogging and Cleaning

Abstract

Pore clogging in porous asphalt pavement (PAP) severely limits its functional performance and widespread application. This study systematically investigates the permeability degradation and recovery characteristics of seven porous asphalt concrete (PAC) with varying air void contents (16%, 18%, 20%, 22%, and 24%) and nominal maximum particle sizes (9.5, 13.2, and 16 mm). Three clogging materials (diabase fine aggregates, clay, and their mixture) and three cleaning methods (high-pressure water, vacuum suction, and combined methods) were applied through repeated clogging-cleaning cycles. Key findings reveal that PAC with higher void content (24%) and larger nominal particle size (16 mm) exhibits superior anticlogging performance, while mixtures with lower void content (16%) suffer rapid permeability loss. Critical clogging particle sizes expand with increased void content and nominal particle size. Vacuum suction and its combination with high-pressure water achieved the highest permeability recovery rates (60%–85%), outperforming high-pressure water alone (35%–64%). Grey correlation analysis further highlights void content as the dominant factor influencing clogging resistance. This work provides practical insights for optimizing PAP design and maintenance strategies to mitigate clogging issues.