Alongside implementation of green roofs and vegetation covers, cool pavements have been recommended for urban temperature reduction. Together with anthropogenic activities, the phenomenon of global climate changes is also a key contributor to the observed rise in urban temperatures. Statistics and scientific studies show that summer temperatures in cities are 6 ☌ higher than in suburbs. The UHI effect on the urban environment is related to the high temperature destruction of urban asphalt pavement which has several adverse effects on urban construction. The Urban Heat Island (UHI) phenomenon explains the undesirable situation whereby the urban areas’ temperature is higher than the surrounding suburban and rural areas, which has recently been of great concern. The thermal radiation model reveals that the pavement equilibrium temperature combined with the MIRP in asphalt mixture decreases with the increase of the longwave emissivity, and it diminishes with the decrease of the shortwave absorptivity. Compared with limestone mineral powder asphalt mortar, the asphalt mortar with MIRP had a more compact structure and uniform distribution, and enhanced the overall structural performance of the mixture. The results show that the main components of MIRP are metal oxides and nonmetallic oxides which improve its infrared emissivity. According to the radiant heat transfer theory, a thermal radiation model of the pavement equilibrium temperature was established by microscopic and chemical analysis to study the influence of thermal radiation asphalt mixture and reveal its cooling performance. X-ray diffraction analysis and scanning electron microscopy test (SEM) were conducted to analyze the chemical composition and the microstructure of MIRP, respectively. Based on the physical apparent density tests of materials and infrared thermal radiation test, the cooling performance of MIRP was obtained. This research studied a new material named modified infrared powder (MIRP) for decreasing the high temperature of asphalt pavements which can help alleviate the urban heat island effect to some extent.
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