Experimental study on the thermal characteristics of urban mockups with different paved streets.

Pavements in urban area absorb more sunlight due to the canyon-like geomorphology of the urban geometry and store more heat due to the great thermal bulk properties of concrete. Heat released from pavements warms up the urban air, contributing to the urban heat island. Recently, the uses of cool pavements to reduce the pavement temperature as an urban heat island mitigation have gained momentum. Understanding the temperature and solar insolation of a pavement in an urban area is important to adopt the right cool pavement option for the right place. This study measured the temperature of paved streets in an urban mockup for 4 days in summer. It is found that east-west (EW) streets are the hottest place in an urban area, followed by the intersection, and finally the south-north (SN) street and that increasing the pavement's albedo reduces the pavement temperature effectively. The dark gray pavement in an open space is hotter than that in an urban canyon. The heat storage in the building blocks keeps the pavement warmer more than 2 °C at nighttime. The EW street is exposed to solar insolation for long hours, so it is suitable for preferentially developing reflective cool pavements.