Rheological characterization of asphalt binders treated with bio sealants for pavement preservation

Pavement preservation is playing an increasingly significant role in maintaining our aged pavement infrastructure under severe budget constraints. One important component is the use of surface treatments based on application of sealants. Recently, a number of new products, called bio sealants, have been used to treat aging pavement surfaces. The objective of this study is to investigate rheological properties of the binders treated with these materials to understand the mechanism by which they may improve pavement performance. One plain asphalt binder and four types of sealants, two oil-based sealants, one water-based sealant, and one traditional emulsion were used in the experimental work. The results obtained using a dynamic shear rheometer and a bending beam rheometer were used to determine the changes in rheological properties and the change in performance grade. It was observed that the oil-based sealants have a significant softening effect of the control binder compared to the water-based sealants. The transverse cracking histories from field investigation were used to verify the laboratory findings.