Using the Rheological Index to Quantitatively Evaluate the Mechanical Performance of High-Elasticity Modified Asphalt

Abstract

High-elasticity modified asphalt is widely used in OGFC and bridge deck paving due to its high viscosity and strong displacement recovery capacity. It can improve the high-temperature deformation resistance and elastic recovery ability of the pavement. Especially in bridge deck pavement, high-elastic modified asphalt can inhibit the formation of reflective cracks and extend the service life. In order to quantitatively evaluate properties of the high-elasticity modified asphalt, rheological properties are studied by using a dynamic shear rheometer (DSR) test. The parameters were fitted with the Burgers model, and the constitutive equation was established. The 3 s elastic recovery rate $E_r$ was proposed to quantitatively evaluate the elastic recovery of high-elasticity modified asphalt. The experimental results show that the instantaneous modulus of elasticity $G_0$ and the delayed modulus of elasticity $G_1$ can be used to evaluate the elastic capacity. $E_r$ can quantitatively evaluate the elastic resilience of high-elasticity modified asphalt. The correlation coefficient between the test results of high-elasticity modified asphalt and those of impact toughness evaluation reached 0.9966, and the 3 s elastic recovery rate $E_r$ could be used to evaluate the elastic recovery ability of high-elasticity modified asphalt.