A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Transportation Engineering, School of Engineering and Technology

Thesis (M.Eng.) - Asian Institute of Technology, 2007

Innovations in the asphalt pavement industry continue to evolve, and the latest is the WMA technology, which has been used in the United States, Africa, Europe and some parts in Asia. WMA is the technology to produce and construct asphalt mixtures by lowering the production temperature of HMA. One of the processes to reduce the temperature of HMA is to modify asphalt binder with Sasobit®. Since this technology is relatively new in Thailand, there is a need to comprehensively evaluate its applicability in the country. In this study, the fundamental properties of asphalt binders modified with Sasobit® including the viscosity, rheological properties, rutting, and fatigue resistance, were evaluated. In addition, the compactability of mixtures was also investigated to determine whether the mixes can reach the desired density at lower temperatures. The performance related properties of the asphalt mixtures including the rutting resistance, fatigue resistance and moisture damage resistance were also assessed. The materials used namely, 9 mm nominal limestone aggregate, AC 60/70 and PMA asphalt binders as well as Sasobit® were provided by the Depa1tment of Highways, Thailand. The asphalt mixtures were designed according to the Marshall mix design method which is commonly used in Thailand. The test results indicate that Sasobit®-modification improves the compactability of the asphalt mixtures at reduced temperatures. It improves the performance-related properties of asphalt binders including viscosity, viscous-elastic behavior, rutting resistance, and fatigue resistance, and also the properties of asphalt mixtures including the rutting resistance, fatigue resistance and moisture damage resistance. This shows the potential of Sasobit® for WMA application in Thailand.