Preparation and evaluation of cooling asphalt concrete modified with SBS and tourmaline anion powder

Abstract With the growth in traffic volume worldwide, the warming of the road surface in hot seasons has become an important factor, as it intensifies the greenhouse effect. In this study, tourmaline anion powder (TAP), an inorganic material, was used as a new environmentally friendly asphalt modifier for the development of active pavement cooling asphalt concrete (APC-AC). SBS-modified asphalt was used to be modified with different contents of TAP. To determine the optimal TAP content as to achieve the best high and low temperature performance, asphalt rheology tests were conducted. Then the samples were aged in a rotating film oven and pressure aging chamber to investigate their anti-aging properties. A storage stability evaluation method suitable for TAP/SBS-modified asphalt was developed. Based on the test results of the TAP/SBS-modified asphalt, APC-AC specimens with different TAP contents were developed. To study the cooling performance of the developed APC-AC, laboratory temperature difference tests and outdoor illumination tests were performed. The thermal parameters of the APC-AC were also studied. Finally, a rutting test was performed. Based on the test results, the developed APC-AC exhibited outstanding cooling ability and excellent road performance.