Shape optimization of thermal shape memory epoxy resin and its mechanism for improving the self-healing of asphalt mixtures

Thermal shape memory epoxy resin (T-SMER) is a novel smart material. The shape memory effect of T-SMER is stimulated by sensing and responding to temperature changes in the asphalt mixtures. The shape memory effect of T-SMER can be used to repair initial cracks in the asphalt mixtures. T-SMER’s shape can influence its shape memory effect and ability to improve the self-healing property of the asphalt mixtures. It also affects the performance of asphalt and asphalt mixtures. Therefore, granular T-SMER and filamentous T-SMER were prepared in this study, and their basic properties were examined. To determine the T-SMER shape with better shape memory effect, the three major indicators and elastic recovery performance of asphalt with granular T-SMER were tested, AC-5 asphalt mixture and AC-10 asphalt mixture with granular T-SMER were formed. Although the granular T-SMER improved the self-healing property of asphalt, its compatibility with asphalt was poor, and there existed a swelling phenomenon in AC-5 and AC-10 asphalt mixture. The adhesiveness between the asphalt and filamentous T-SMER, Marshall indexes, and preliminary study on self-healing property of the asphalt mixtures with the filamentous T-SMER were also investigated. The addition of the filamentous T-SMER significantly increased the consistency of asphalt, improving its strength and self-healing. Thus, the filamentous T-SMER was more suitable for application in the asphalt mixtures. To study the mechanism of the filamentous T-SMER for improving the self-healing property of the asphalt mixtures, the visualization of asphalt mixtures with filamentous T-SMER self-healing process by ANSYS were analyzed. The shape memory ability of the T-SMER can be stimulated to enhance the self-healing property of asphalt mixtures.