Search

• PP fiber and nano-TiO 2 modification improves the road performances of PMM. • The optimum ratio of PP fiber and nano-TiO 2 in PMM has been determined. • The PMM showed excellent photocatalytic exhaust degradation capacity. • The PMM significantly reduces the energy consumption and greenhouse gas emissions. To purify severe air pollution in traffic-intensive urban areas and tunnels, an innovative type of photocatalytic micro-surfacing mixture (PMM) was designed, which was enhanced by polypropylene (PP) fiber and nano-TiO 2. In this work, the road performance of sixteen PMMs with the different contents of PP and nano-TiO 2 were evaluated by wet-track abrasion test, wheel rutting deformation test and low-temperature splitting test. The vehicle exhaust (VE) gas degradation capacity of sixteen PMMs was characterized under ultraviolet (UV) light and visible light conditions. The life cycle assessment (LCA) methodology was applied to evaluate the environmental impact of PMM. The results showed that the road performances of PMM were improved with the increase of the PP fibers amount. The VE gas degradation capacity was significantly enhanced with the increase of nano-TiO 2 amount. PMM with 0.2 wt% PP fibers and 60 wt% replacement of mineral filler with nano-TiO 2 was a viable alternative to improve photocatalytic degradation of VE in pavement engineering. In addition, the modified micro-surfacing mixture facilitates a significant reduction in energy consumption and greenhouse gas emissions. [ABSTRACT FROM AUTHOR]