Aging performance of high viscosity modified asphalt under complex heat-light-water coupled conditions.

• The coupled heat-light-water aging device has been proposed and developed. • The aging performance of HVA in complex environmental conditions was investigated. • The significance of different aging factors on road performance of HVA were demonstrated. • The microstructural morphologies revealed the aging mechanisms. During the rapid development of sponge city construction in China, the porous asphalt pavement has been widely applied. The high viscosity modified asphalt that is used for producing porous asphalt experiences complex aging circumstances. In this study, the aging performance of high viscosity modified asphalt was evaluated based on the simulated heat-light-water coupled conditions, in which different aging effects and degrees were considered. The complex aging simulation method was innovated that mainly composed of an UV radiator and an environmental cabinet. The dynamic shear properties, high and low-temperature performance, and microstructural morphology of aged high viscosity modified asphalt binders were evaluated through the DSR (temperature-frequency sweep scan, LAS, MSCR), BBR, and ESEM tests, respectively. The results of DSR and BBR test demonstrated that the coupled aging effects should be considered during the service period, since acid rain solution and UV light also led to significant influences on the viscoelastic properties, high and low-temperature performance, and fatigue performance as similar as high temperature. The observation of the microstructures illustrated the aging mechanisms of different environmental factors and their combined effects. This study could provide a better protocol for aging performance examination of high viscosity modified asphalt binder used for porous asphalt pavement considering complicated environmental conditions. [ABSTRACT FROM AUTHOR]