Nano TiO2/ARA composite modified asphalt mixture mix ratio design and road performance research

To address prevalent asphalt pavement distresses such as rutting and water damage in hot and rainy regions, this study developed a nano-TiO 2 /Albanian rock asphalt (ARA) composite modified asphalt. This modification aims to enhance the high-temperature performance and water stability of asphalt pavements while reducing the consumption of petroleum asphalt. The mix design was optimized via the Response Surface Methodology (RSM), which determined the optimal modifier dosages to be 1.3% for nano-TiO 2 and 16.0% for ARA. The road performance of the optimized composite mixture was evaluated and compared against single-modified and base asphalt mixtures. Results demonstrated that the nano-TiO 2 /ARA composite modified asphalt mixture possesses significantly superior high-temperature stability and water stability over both single-modified and base asphalt mixtures, while still complying with low-temperature performance specifications. It can be concluded that the nano-TiO 2 /ARA composite modified asphalt exhibits comprehensive excellent road performance and shows considerable potential in mitigating rutting and water damage in asphalt pavements in hot and rainy climates.