Leveraging Product and Process Characteristics Across the Concrete Pavement Life Cycle to Integrate Global Warming Potential into Project Procurement Processes

Abstract

The objective of this research is to support sustainable procurement of concrete pavements by linking materials-level global warming potential (GWP) to the project-level. Infrastructure owners require reliable environmental product declarations (EPDs) and methodologies for integrating GWP into the procurement process to ensure equitable decision-making. This work provides insights into current EPD reliability by assessing the sensitivity of concrete GWP to materials-level contributors to recommend a level of supply chain specificity needed to effectively communicate GWP. A benchmarking methodology was developed and implemented to establish reference values for procuring sustainable products. Having provided evidence towards EPD reliability, this work presents a framework that integrates GWP with pay items in project specifications. Linking incentives within infrastructure owner specifications to desired performance characteristics encourages all involved stakeholders to prioritize achievement of those performance characteristics. This same concept can be applied using GWP as the desired performance characteristics. A data collection protocol and life cycle information model (LCIM) for concrete pavement construction were developed to facilitate GWP integration into current project procurement practices. The LCIM methodology was developed and implemented to estimate the production and construction environmental impacts of six real-world concrete pavement construction projects. Applying the LCIM methodology allowed this work to map GWP to pay items and incentives in specifications and provide a pathway to extend a LCIM across the life cycle. The LCIM was further demonstrated on a real-world joint repair project, as well as for a concrete pavement reconstruction, demolition, and waste hauling. The culmination of this research demonstrated that the LCIM can be used to estimate the embodied environmental impacts of a concrete pavement across its life cycle and provided a framework for integrating environmental impacts into the procurement process, facilitating sustainable project procurement for infrastructure owners