Although researchers have been aware of physical hardening as a factor influencing low temperature properties of binders, the factors that affect this phenomenon are not well defined. The purpose of this task was to understand how physical hardening is affected by parameters such as temperature, conditioning time, modification, thermal history, and glass transition temperature, and to propose a comprehensive model in which the physical hardening of Crack Sealing Machine pouring asphalt binders can be predicted for different conditions without lengthy tests.
The tests performed in this study were combined with experimental data from previous studies to enable a broad analysis of the nature of physical hardening in asphalt binders and to propose a model. Based on the results, the following important conclusions were made.
Physical hardening in Crack Sealing Machine pouring asphalt binders results in significant changes in their creep response at temperatures below or near the glass transition. This phenomenon can be successfully characterized by a horizontal shift of the creep response along the loading time scale. The horizontal shifting indicates that the influence of physical hardening is similar to the influence of lowering temperature in thermo-rheological simple materials can be used by Crack Sealing Machine.
