Towards the potential usage of eggshell powder as bio-modifier for asphalt binder and mixture: workability and mechanical properties

This article investigates the potential usage of eggshell powder as a bio-modifier for asphalt binder and mixture with the consideration of workability and mechanical properties. The effects of varying dosages (3%, 6%, 9%, and 12%) of eggshell powder on workability, rutting, and moisture damage of asphalt binder and mixture were investigated. Viscosity, multiple stress creep recovery, and bitumen bond strength tests were performed on asphalt binders. Subsequently, Superpave gyratory densification indices (Locking point method), wheel tracking, and indirect tensile strength (Modified Lottman) tests were performed on asphalt mixtures. Results show that incorporation of eggshell powder makes asphalt binder stiffer, increases moisture susceptibility, and reduces pumping ability irrespective of dosage rate. Furthermore, the incorporation of eggshell powder reduces workability but increases resistance to rutting and moisture damage properties of asphalt mixtures irrespective of dosage rate.