Rheological investigation of a super-tough resin-based binder for steel bridge deck paving

•The curing-induced viscosity evolution models of EA and STR were established.•At 70 °C, there is little residual strain in EA and STR specimen in MSCR test.•The dissipated energy and shear stress of STR were obviously higher than EA.•At −10 °C, the elongation of STR is remarkably higher than that of EA. Epoxy asphalt concrete is extensively utilized as the steel bridge deck paving material due to its excellent engineering performance. However, the harsh service environment of steel deck with significant deformation poses a great challenge to its durability. Therefore, it is necessary to explore new binders with better compliance and stability performance. In this research, a super-tough resin (STR) with good high-temperature stability and low-temperature flexibility was developed as the steel bridge deck pavement binder. The rheological properties of STR were comprehensively investigated and compared with the epoxy asphalt (EA) and traditional SBS-modified asphalt. Specifically, the reaction-induced viscosity evolution, high-temperature stability, intermediate-, and low-temperature crack resistance, and tensile performance were evaluated. According to the results, the viscosity evolution rate of STR increases significantly with increasing temperature. At intermediate temperatures, the linear viscoelastic regions of STR and EA concentrate around 1%. At 70 °C, the non-recoverable compliance and percent recovery of STR and EA are all lower than 0.01kP-1 and higher than 99.8%, respectively. In the linear amplitude sweep (LAS) test, the dissipated energy and shear stress of STR were significantly higher than that of EA and SBS-modified asphalt and reveals better crack resistance at intermediate temperatures. Besides, the low temperatures could significantly increase the stiffness and decrease the flexibility of STR and EA. However, even at −10 °C, the elongation of STR was 97%, which is remarkably higher than that of EA and demonstrates favorable flexibility. To sum up, STR is a stiffer, more flexible, and stable binder than EA, which shows promise for more durable steel deck paving applications.