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Cool asphalt pavement is the pavement with reduced surface temperature by employing using a reflective coating,thermal resistance materials,water-permeable/remaining materials or other methods.Thermochromic materials,materials that can change their color variable in response to temperature,reflect solar energy at high temperatures and accept that at low temperatures.Both of these factors can reduce surface temperature of a paved road.In this study,cool asphalt pavement is designed by incorporating thermochromic materials into asphalt mixture.Thermal performance of cool asphalt pavement is investigated with numerical simulation and field tests.By using COMSOL software,a threedimensional element model was proposed to mimic the thermal characteristics of an asphalt pavement based on measured climate data in Muzaffarabad,AJK.Temperature measurements showed that higher temperatures of asphalt concrete could be reduced to 4.7 °C in May and increased to 1.3 °C in February,respectively compared to conventional asphalt concrete.The corresponding temperature gradient across the mound can be reduced to 16.5 K/m and 13.7 K/m respectively.These concrete results have the advantage of reducing operational damage associated with high temperatures of the paved road,in order to improve the durability and safety of the asphalt pavement,and to reduce the thermal effects of urban islands.Comparative practical studies were used with the aim of investigating the effect of materials on changing the temperature of the asphalt paved surface,and thereby proving its suitability for improving its durability.In total,standard asphalt concrete and asphalt concrete containing black,blue and red materials were studied respectively,from April to June,2021,for 24 hours.To investigate the thermal performance of thermochromic asphalt concrete,higher temperatures were measured and analyzed in detail.It has been shown that temperatures higher than thermochromic asphalt concrete may be 5.8 °C,6.1 °C and 3.4 °C cooler than standard asphalt concrete under hot summer conditions and 0.3 °C,1.5 °C and 1.7 °C warm at night by using black,blue and red thermochromic materials,respectively.In addition,the temperature fluctuations of asphalt concrete were found to be reduced to 4.5 °C,3.8 °C and 2.9 °C by means of black,blue and red thermochromic materials,respectively.In addition,compared with standard asphalt concrete,thermochromic asphalt concrete delivered 2.28 °C/h and 0.66 °C/h low temperatures and cooling below the summer day,respectively.These contributions demonstrate the power of thermochromic materials when used in asphalt concrete to improve service life and safety of asphalt concrete.