Dynamic Life-Cycle Modeling of Pavement Overlay Systems: Capturing the Impacts of Users, Construction, and Roadway Deterioration

Pavement systems provide critical infrastructure services to society but also pose significant impacts related to large material consumption, energy inputs, and capital investment. A life-cycle model was developed to estimate environmental impacts resulting from material production and distribution, overlay construction and preservation, construction-related traffic congestion, overlay usage, and end of life management. To improve sustainability in pavement design, a promising alternative material, engineered cementitious composites (ECC) was explored. Compared to conventional concrete and hot-mixed asphalt overlay systems, the ECC overlay system reduces life-cycle energy consumption by 15 and 72%, greenhouse gas emissions by 32 and 37%, and costs by 40 and 47%, respectively. Material, construction-related traffic congestion, and pavement surface roughness effects were identified as the greatest contributors to environmental impacts throughout the overlay life cycle. The sensitivity analysis indicated that traffic growth has much greater impact on the life-cycle energy consumption and environmental impacts of overlay systems compared to fuel economy improvements.