Despite popularity in the construction industry, the widespread use of petroleum-based asphalt binders is accompanied by high material costs due to the volatility of the petroleum market and negative environmental impacts. In order to fulfill the global economic and environmental need for sustainable construction materials, the construction industry needs novel binder materials to act as direct alternatives (i.e., 100% replacement) for petroleum-based asphalt binders. This research evaluated highly concentrated agar hydrogel composites (i.e., agar and calcium carbonate filler) for use as direct alternatives to petroleum-based asphalt binders. The rheological (i.e., rotational viscosity, dynamic shear rheology), softening point, and penetration properties of unaged agar-based binders were characterized and compared to conventional petroleum-based asphalt binder specifications. Agar-based binders exhibited a higher rotational viscosity than petroleum-based binders, but illustrated the potential for lower handling, placement, and compaction temperatures. In dynamic shear rheology testing, agar-based binders illustrated adequate resistance to rutting at temperatures ≤ 70ºC. Agar-based binders exhibited a higher softening point than petroleum-based binders, indicating improved resistance to deformation at high service temperatures. The penetration of agar-based binders was found to vary depending on moisture and filler concentration, which indicates the possibility of consistency tailorability. In addition to these results, preliminary moisture absorption and thermal stability data will be presented, along with plans for future work oriented on evaluating perceived environmental benefits and the associated life cycle cost.                                                                

Biobased Alternative Asphalt Binders from Agar: Baseline Properties and Future Directions

Welcome to the International Airfield and Highway Pavements Conference of the Transportation & Development Institute (T&DI) of ASCE. This international conference will provide an unrivaled chance to interact and exchange information with worldwide leaders in the fields of highway and airport pavements, as well as airport safety technologies.

This conference will bring together designers, project/construction managers, academics, and contractors from around the world to discuss the state-of-the-art implementation, construction, design, in airfield and highway pavements.

Paper Proceedings: https://doi.org/10.1061/9780784483527 | https://doi.org/10.1061/9780784483503 | https://doi.org/10.1061/9780784483510

Conference DOI: https://doi.org/10.26226/m.63284d15cb3e8e0012755dd4