Effect of humid and thermal environments on the performance of an epoxy resin pavement filling joint material

Abstract

Modified epoxy resins have shown good results for the repair of pavement cracks. However, as the grouting material is directly exposed to the atmosphere, its performance is affected by humid and heat, resulting in a certain deterioration in its performance and service life. To explore the influence of humid and heat on an epoxy resin joint filling material (EPFM), EPFM was treated in humid and thermal environments for varying periods of time in this study, and the water absorption characteristics, mechanical properties, and road performance of the EPFM were tested. The stress relaxation index was used to evaluate the stress relaxation performance of the EPFM after humid and heat treatments. The results show that in a humid environment, EPFM undergoes a three-stage water absorption process, and the increase in water content reduces its glass transition temperature. In low-temperature environments, the tensile and shear strengths of the EPFM are reduced, but the deformation properties are enhanced under different stress patterns. In a high-temperature environment, the internal macromolecular structure of the EPFM is damaged, causing a significant reduction in its toughness. Under the −10 °C test conditions, the tensile strength reaches a maximum of 31 MPa, and the elongation at breaking decreases to less than 60 %. Through stress relaxation tests, it is found that compared with the thermal environment, water further weakens the stress relaxation performance of the EPFM.