Nanomaterials in asphalt pavements: A state-of-the-art review

This study adopts a systematic literature review approach to investigate the diverse applications of nanomaterials in asphalt pavement, marking the convergence of nanotechnology and asphalt pavement industry. Nanomaterials, characterized by their unique properties at the nanoscale, encompass a variety of materials, including nanoclay, nano-silica, carbon nanotubes, and nanofibers, and have gained increasing attention for their potential to revolutionize the asphalt industry. By incorporating nanomaterials, industry can achieve greener production processes, lower energy consumption, and promote the use of sustainable, recycled materials. A central focus of this review is the examination of how key properties of asphalt mixtures are influenced by nanomaterials, including mechanical characteristics such as stiffness, strength, and flexibility, as well as their role in enhancing resistance to common distress modes such as rutting, cracking, and moisture damage. Additionally, their impacts on temperature susceptibility and aging characteristics are explored. The mechanisms underpinning nanomaterial reinforcement in asphalt are elucidated, encompassing nanoparticle dispersion, interfacial bonding, and confinement effects. These mechanisms offer a deeper understanding of the science behind the improved performance. Environmental and sustainability considerations associated with the incorporation of nanomaterials into asphalt are addressed, including potential environmental risks and health implications. Emphasis is placed on sustainable practices, such as the use of recycled materials and energy-efficient production methods. This review underscores current challenges and limitations in the field and provides insights into the future directions of research and innovation. It envisions a roadmap for harnessing nanotechnology's transformative potential in asphalt pavement engineering.