Pedestrian-path pavement materials to improve microclimate and air quality on current pedestrian paths

Abstract

In this study, I investigated pavement materials to improve the microclimate and air quality of pedestrian paths on streets in Seoul, South Korea. Existing pedestrian-path pavement materials were assessed, and several pavement materials were simulated. Asphalt had greater air (Ta) and ground surface (Tg) temperatures than the granite pavement. The granite pavement had a greater mean radiant temperature (Tmrt) and physiologically equivalent temperature than asphalt. Asphalt had a 3.2-times higher sensible heat flux than the granite pavement. The granite pavement reflected approximately 3.9-times more radiation than asphalt and emitted lower NO2 and NOx concentrations than interlock blocks. The high-albedo granite pavement showed a low Ta, and the high-albedo granite pavement + grass showed a low Tg; these Ta and Tg values were lower than those of asphalt. The grass pavement had lower Tmrt and PET values, than the granite pavement. The high-albedo granite pavement exhibited an endothermic phenomenon during the day, whereas grass showed a high sensible heat flux due to an exothermic phenomenon. The granite pavement, with higher albedo, reflected approximately 2.7-times more radiation than the unmodified granite pavement. High-albedo granite pavement material had the lowest NO2 and NOx concentrations, which were lower than those of interlock blocks.