Laboratory Study on Performance Evaluation and Automobile Exhaust Degradation of Nano-TiO2 Particles-Modified Asphalt Materials

Automobile exhaust pollution is a serious problem that restricts urban development, and it poses a serious threat to people’s lives and health and even the climate. At present, the treatment of automobile exhaust has attracted people’s attention, and numerous works have been focused on it thereafter. The purpose of the present study is to drive TiO2 nanoparticles application into pavement, and the study present an experimental investigation of performances and automobile exhaust purification of asphalt and its mixture modified by nano-TiO2. In this work, a series of rheometer properties and pavement performances were studied, including penetration, softening point, ductility, DSR and BBR for asphalt binder, conventional pavement performances, and creep test for asphalt mixture. Moreover, the photocatalytic degradation test of automobile exhaust was conducted to assess degradation of TiO2 nanoparticles in the asphalt mixture on automobile exhaust. Results indicate that the TiO2 nanoparticle was beneficial to increase the viscosity and reduce the temperature sensitivity, which would enhance its high-temperature stabilization capability of asphalt. Meanwhile, nano-TiO2 can significantly enhance the rheometer properties of asphalt and its capacity of high-temperature antirutting, and its low-temperature performance could also comply with the specification. Besides, the incorporation of nano-TiO2 in mixtures could effectively enhance the antirutting and anticracking as well as water stabilization. Moreover, the nano-TiO2-modified asphalt mixture possesses a positive impact on photocatalytic degradation of CH and NOx, which could provide a reference for the treatment of automobile exhaust. The photocatalytic degradation effect of asphalt mixtures modified by nano-TiO2 on NOx is significantly better than that of CH.