Sustainability Benefits of Adopting Geosynthetics in Roadway Design

The world’s roadway system is so extensive that its total length would encircle the Earth over 1,600 times if combined. Geosynthetics have provided sustainable alternatives in roadway projects, representing a significant portion of the total usage of geosynthetics in civil infrastructure. Yet, considering the significant extension of roadway projects worldwide, geosynthetic products are only utilized in a small fraction of them. Consequently, the opportunities to achieve sustainability goals by making more extensive use of geosynthetics in roadways are massive. The objective of this paper is to illustrate the sustainability benefits of adopting geosynthetics in roadway design. This is accomplished by quantifying the carbon footprint for six roadway projects, each involving at least two alternative designs: One with and the other without using geosynthetics. Each roadway project involved one of six different applications involving the use of geosynthetics. Specifically, they involved the use of geosynthetics to (1) mitigate reflective cracking in structural asphalt overlays, (2) stabilize unbound aggregate layers, (3) reduce layer intermixing, (4) reduce moisture in structural layers, (5) stabilize soft subgrades, and (6) mitigate distresses caused by expansive clay subgrades. The sustainability benefits were quantified by conducting carbon audits for the alternative designs for each roadway project. The results of the analyses indicate that the design alternatives involving geosynthetics always proved more sustainable than the conventional (without geosynthetics) alternatives, resulting in savings in the total carbon footprint that ranged from 16.3 to 44.44 tCO2e per lane-km (or 11.6 to 50.11