Development of cold-mix high-toughness resin and experimental research into its performance in a steel deck pavement

Fatigue cracking is a typical defect in steel deck pavements. To reduce, or even eliminate, fatigue cracking in orthotropic steel deck pavements, a new-generation, cold-mix, high-toughness resin (CHR) for steel deck pavements was prepared by introducing a flexible chain into the molecular structure of cured epoxy resin based on the principle of action of a simultaneous interpenetrating polymer network (IPN). Meanwhile, the strength and durability of the CHR were studied experimentally. The results show that, with increased dosage of active toughening agent, the microstructure of CHR transitioned from a sea-island structure to an interpenetrating network structure. In addition, the transparency of CHR gradually increased and the tensile strength gradually decreased while the elongation at break gradually increased. The reaction orders of Z15-G1 and Z15-G2 CHRs were 0.918 and 0.921 and their apparent activation energies were 47.60 kJ/mol and 50.74 kJ/mol, respectively. The basic pavement performances of the Z15-G1 and Z15-G2 CHR mixtures both satisfied the technical index requirements of a steel deck pavement. Moreover, four-point bending fatigue test results show that the fatigue life of the Z15-G1 CHR mixture was much longer than that of an epoxy asphalt mixture.