Introduction of mechanistic-empirical pavement design into pavement carbon footprint analysis

Abstract

Transportation authorities and industrial organisations are currently faced with the need to incorporate greenhouse gas (GHG) impacts into pavement designs. GHG emissions have been evaluated for individual projects with unique external environments. These estimates cannot be applied to future projects with different external environments. This paper presents a GHG estimation method to assist in low-carbon design for future pavement construction. The method uses mechanistic-empirical pavement design guide to create comparable structures with different pavement techniques, traffic volumes, climate conditions, etc. The method is illustrated using the Maryland Intercounty Connector (ICC) project, which was paved with hot mix asphalt. The results show that if the ICC’s asphalt base layer was paved with foam stabilised base, GHG emissions would be reduced by up to 18.8 thousand metric tons, an equivalent to 56.5% of the total pavement construction emissions. The GHG savings would generate $111,200 of carbon offsets, which compensate approximately 5.7% of the pavement costs.

Keywords:

• Greenhouse gas
• mechanistic-empirical pavement design
• hot mix asphalt
• foam stabilised base
• technique selection
• life cycle assessment

Acknowledgements

The authors appreciate Harold Green, Sara Berman, Dan Shaw, Chandra Akisetty and Yujie Lu, who provided FSB project data and feedback on GHG emission calculations. Thanks are extended to the contacts from sixteen HMA plants, along with Mike Burke who helped us collect the data.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the Global Emissionairy, LLC and Maryland Industrial Partnership Grant.