A comprehensive review on the usage of nanomaterials in asphalt mixes

The growing demand for infrastructural developments has boosted the expansion of road networks, and the developers are not only focusing on road lengths but also trying to construct a road that can provide long-term serviceability and durability. A variety of asphalt modifiers are being used by researchers to improve the overall performance of flexible pavements. The current study focuses on collecting various research works related to the application of nanomaterials for asphalt modification and performs a detailed review of the available literature. The majority of the research works available around the globe are collected and the effects of the addition of various types of nanomaterials in the behavior of asphalt as well as asphalt mixes are reviewed. Initially, several types of nanomaterials are identified which are mostly used for asphalt modification. Then their mixing processes, dispersion behavior, performances, etc. are reviewed, followed by the challenges involved in nano modification and their cost considerations. Finally, the research gaps are identified and the future prospects of nano modified asphalt mixes are ascertained. The overall review of the available studies has indicated the benefits of nanotechnology in pavement construction; however, using nanomaterials in asphalt mixes is a bit challenging due to the lack of practical implications and proper knowledge. The life cycle cost analysis, standard guidelines, mixing methods, etc. are also not available properly and requires further research for the full-fledged application of several nanomaterials for asphalt modifications.