Study on Hot-Mix Epoxy Resin Based on Glass Transition Temperature and Its Application for Steel Bridge Deck Pavement

There are many kinds of hot-mixed epoxy resins on the market with uneven performance, which makes it difficult to select the excellent performing material. This study investigated the effects of glass transition temperature (T-g) on epoxy resins, epoxy asphalts, and epoxy asphalt mixtures, aiming to confirm the T-g is an effective way to quickly select optimum epoxy resin materials. Specifically, the macromechanical properties, microproperties, and rheological properties of epoxy resins, epoxy asphalts, and epoxy asphalt mixtures were evaluated by a tensile and viscosity test, a dynamic mechanical thermal analysis test, a scanning electron microscope (SEM) test, and a dynamic shear rheometer test. Results indicate that the performances of epoxy resins, epoxy asphalts, and epoxy asphalt concretes have closely related with T-g. With T-g increasing, the tensile strength, Marshal stability, and dynamic stability are increased, while the elongation at the break, flexural tensile strains, fracture energy, and viscosity are decreased. In addition, the enhanced T-g may boost the deformation resistance of epoxy asphalts. Furthermore, the activity energy of HB, CW-HBP, and TAF is -42.86 kJ/mol, -40.79 kJ/mol, and -53.97 kJ/mol respectively, which demonstrate that T-g has no correlation with the activity energy. Besides, according to the SEM test result, the lower T-g can make epoxy resins experience ductile fracture, while higher Tg can make the HB epoxy resin experience brittle fracture. Finally, the T-g can be used to qualitatively compare and quickly select the optimum hot-mix epoxy resin used in long-span steel bridge deck pavement. (c) 2024 American Society of Civil Engineers.