Intermediate Temperature Fatigue and Low Temperature Cracking Properties of Rubber Asphalt Binder

摘要

As an environmentally friendly pavement material, a 20 mesh crumb rubber was blended in Superpave performance grade PG64-22 binder to make crumb rubber modified (CRM) binders with 10%, 15%, 20% and 25% content, respectively. Two main indices, |G*|.sin(5) obtained from the dynamic shear rheometer (DSR) test, and creep stiffness obtained from the bending beam rheometer (BBR) test, were applied to characterize the intermediate and low temperature rheological performance of CRM binders. Statistical analysis of variance (ANOVA) was applied to investigate the significance level of testing temperature, rubber content and their interaction on the rheological performance of CRM binders. The test results show that the addition of crumb rubber significantly improves the intermediate temperature fatigue and low temperature cracking performance of asphalt binder. 10% content crumb rubber lowers the low temperature grade from -22 to -28 °C. Higher rubber content makes better rheological performance of the CRM binder. From the point of view of cost-efficiency, the suggested rubber content should not exceed 20%.