Increasing the sustainability of our infrastructure is accomplished in ways other than just developing better materials and using recycled materials: it is also about employing the right designs. For concrete pavements, overdesign and use of poor features causes excess materials to be used during construction, leading to higher economic costs and environmental impacts. Optimizing pavement designs for prescribed service lives, climates, and traffic conditions allows pavement engineers to create structures that have low initial costs and CO2 emissions as well as low life cycle costs and CO2 emissions.
This paper shows how design optimization can lower costs and CO2 emissions by balancing:
- The initial costs and CO2 emissions of a pavement, which are primarily a function of the thickness and specific design features used, and
- The rehabilitation costs and CO2 emissions, which are a function of the pavement’s estimated service life and required rehabilitation activities
To do this, a case study for a California highway is analyzed where the conventional designs are compared against optimized designs from the AASHTOWare Pavement – ME Mechanistic Empirical Pavement Design (Pavement-ME). Life Cycle Cost Analysis (LCCA) and Life Cycle Assessment (LCA) are used to quantify the costs and environmental impacts of the different alternative pavement scenarios and to compare the trade-off between the initial costs and CO2 emissions and successive rehabilitation activities in order to find the “optimized design.” MORE