Laboratory evaluation of the impact of additives on asphalt binders used in cold regions

The objective of this research study is to evaluate the effect of additives (polymers, nanomaterials, and softening agents) on rutting, cracking, and fatigue performance of asphalt binders commonly used in cold regions (PG 52-34 and PG 64E-40). In this study, the first phase consisted of using polymers (Styrene-Butadiene-Styrene, Ground-Tire-Rubber) and nanomaterials (TiO2 and SiO2) to modify two asphalt binders used in cold regions (PG52-34 and PG64E-40). The second phase of the study consisted of adding a combination of softening agents (Corn oil or Sylvaroad) with polymers (SBR, Epoxy, and SBS) to PG52-34 asphalt binder. The performance evaluation was conducted using the Brookfield Viscometer (RV), Dynamic Shear Rheometer (DSR), standard Bending Beam Rheometer (BBR), BBR strength, and Linear Amplitude Sweep (LAS). The testing results showed that the polymers could improve the rutting , cracking and fatigue performance of asphalt binders. GTR improved high and low temperature performance grades, fatigue properties, and strain at failure. Nano-TiO2 and SiO2 did not show a considerable performance improvement compared to SBS and rubber in low temperature and fatigue properties. Results also showed that 7.5% SBS combined with corn oil is considered the best candidate asphalt binder modification to improve the resistance to rutting, fatigue, and thermal cracking