Development of an analytical permeable pavement model for vehicular access areas

Permeable pavements (PPs) are widely used for stormwater control in urbanized areas as they provide absorption and retention of surface runoff. Previous studies on PP systems mainly focus on non-vehicular access areas with light traffic loads where the base usually connects to native soils which allow exfiltration from the bottom. The runoff reduction performance of the PPs in vehicular access areas (PPs-VAA) featured by more complex structure with underdrain outflow control still needs in-depth investigation. In this study, an analytical probabilistic model was developed to quantify the runoff control performance of PPs-VAA taking into account the effects of climate conditions, layer configurations and varying underdrain outflows. The calibration and verification of the proposed analytical permeable pavement model for vehicular access areas (APPM-VAA) were performed by comparing the analytical results with SWMM simulation results. The model was tested in case studies in Guangzhou and Jinan, China, with humid and semi-humid climate conditions, respectively. Close agreement between the results obtained from the proposed analytical model and those from continuous simulation outputs was observed. The proposed analytical model is proved to be capable of rapidly assessing the runoff control performance of PPs-VAA; it can thus be used in the hydrologic design and analysis of permeable pavement systems in engineering practices.