The Effect of Rain on Porous Pavers Daily Temperature Reduction and Environmental Performances

Abstract

Porous paver is becoming the new trend for outdoor paving material. The perceived benefits are mostly related to surface runoff and flood management. At the same time, pavement, porous or otherwise, is the source of increasing temperature in the outdoor environment. How does the wetting of porous pavers from rain help reduce especially the overall environmental temperature remain to be further enlightened. This study observed and measured the pavers and environmental temperatures variations in the same plot during the same time period, as well as their temperatures after rainfall event. By analyzing and transforming the collected data into heat map, charts and mathematical relationship, the mechanism of the temperature reduction could be illustrated qualitatively and quantitatively. The results indicated that the temperature of porous paver is generally lower than that of conventional paver both after rain and without rain by 7.75%. While the environmental temperature of air above porous paver is also generally lower than that of conventional paver by 1.04%. The fact that rain could further reduce the environmental temperature, future works should be focused towards a wetting system for porous pavers during dry season. Porous paver is superior to conventional paver in terms of impact on environmental temperature and especially suitable for sidewalk, parking lot and other large area involving pedestrians and vehicular traffics.