Novel Backwashing Maintenance Method for Permeable Concrete Pavement: Two-Year Field Study

Abstract

In this study, a novel backwashing maintenance method for permeable concrete pavements (PCP) was developed, and its performance was evaluated via a 2-year field comparative study at two PCP sites. Results showed that regular maintenance can mitigate clogging and extend the service life of PCPs. After 2 years of regular maintenance via hand sweeping, vacuuming, pressure washing, vacuuming followed by pressure washing, and the proposed novel backwashing maintenance method presented in this study, the average surface infiltration rates (SIRs) at the maintenance points (testing locations) were 1.3-fold, 1.3-fold, 1.7-fold, 1.8-fold, and 2.1-fold those of the corresponding control points at the mildly clogged PCP Site 1, and 2.1-fold, 3.5-fold, 6.1-fold, 14.0-fold, and 18.1-fold those of the corresponding maintenance points at the heavily clogged PCP Site 2, respectively. The proposed novel backwashing maintenance method outperformed conventional maintenance methods, but its recovery rate depended on the clogging conditions and the backwashing pore flow velocity in the PCP layer. Further studies are needed to promote the wide application of this novel backwashing maintenance method and prolong the service life of PCPs.