Evaluation of a warm-mix asphalt additive

Abstract

Although several warm-mix asphalt projects have been explored in the USA, Europe, and some countries in Asia, there is a need for the research to evaluate the applicability of warm-mix asphalt in Thailand. In this study, the fundamental properties of bitumen modified with one of the commonly used additives (Sasobit, a long-chain aliphatic hydrocarbon (LCAH)) were evaluated. The properties evaluated included the viscosity, rheological properties, rutting, and fatigue resistance. In addition, the compactability of the mixtures was also investigated to determine whether they could reach the desired density at lower temperatures. It was found that the LCAH modification improved the workability and the fundamental properties of bitumen as shown in better rutting and fatigue resistance, and also in higher complex shear modulus. The measurement of the compactability showed that less energy was required to compact the LCAH-modified asphalt mixtures to the desired density even at 20–40°C below compaction temperature. The mixtures modified with the LCAH had greater resistance to densification under traffic or higher potential to resist permanent deformation. The LCAH had no effect, however, on the resistance of asphalt mixtures to moisture damage, but the reduction of mixing and compaction temperatures could have a detrimental effect on the moisture sensitivity.

Performance properties of polymer modified asphalt binders containing wax additives

“…WMA technology can be used as a method of reducing the heat requirement for pavement operations while at the same time maintaining the integrity of the PMA binder. Several studies have been performed on the incorporation of wax additives into the PMA binder [11,5,15,14,17,16,20,19,21,32,13]. Most of the studies investigated the rheological properties of PMA binder by incorporating Sasobit into the binder.…”

Effects of Sasobit® content on the rheological characteristics of unaged and aged asphalt binders at high and intermediate temperatures

“…The main reason for adding Sasobit ® to asphalt binder is to decrease the mixing and compaction temperatures of asphalt mixes without sacrificing mix properties. Various studies on asphalt binder have shown that Sasobit ® increases the Superpave TM rutting factor (G*/sin d), zero shear viscosity (ZSV) and stiffness of asphalt binders [12][13][14][15][16] . Sasobit ® can be used in conjunction with other additive materials such as crumb rubber.…”

Performance Evaluation of Warm Mix Asphalt Mixtures with Recycled Asphalt Pavement

“…The longer chains help to keep the wax in solution, which reduces the viscosity of bitumen at typical asphalt production and compaction temperatures. Based on the literature, rates for Sasobit ® ranged from 1.0% to 4.0% by weight of the bitumen [31][32][33]. In this research, Sasobit ® content was chosen as 3.0%.…”