Weather aging resistance of different rubber modified asphalts

• Weather aging of rubber modified asphalts was carried out under natural environment.
• Rheological properties of modified asphalts changed with the structural evolution.
• For the given base asphalt, SBSMA showed the worst weather resistance, while TB showed the best.

The service life of polymer modified asphalt strongly depends on its weather resistance because of its exposure to the natural environment. Three most widely used rubber modified asphalts, namely styrene–butadiene–styrene (SBS) modified asphalt (SBSMA), crumb rubber modified asphalt (CRMA) and terminal blend rubber modified asphalt (TB) are exposed outdoor for weather aging. Effect of aging on the chemical composition of different rubber modified asphalts is analyzed by using infrared spectroscopy. The rheological properties of base asphalt and modified asphalts before and after aging are characterized by using the dynamic shear rheometer (DSR) and dynamic mechanical analysis (DMA). Results show that the chemical structure and rheological properties of modified asphalts change significantly as a result of the weather aging. Different rubber modified asphalts show the different aging behavior. For the given base asphalt, SBSMA is the most susceptible to weather aging, followed by CRMA and TB, respectively.