Traffic modelling in system boundary expansion of road pavement life cycle assessment

Galatioto, Fabio; Huang, Yue; Parry, Tony; Bird, Roger; Bell, Margaret

Abstract

This paper uses a case study of a UK inter-urban road, to explore the impact of extending the system boundary of road pavement life cycle assessment (LCA) to include increased traffic emissions due to delays during maintenance. Some previous studies have attempted this but have been limited to hypothetical scenarios or simplified traffic modelling, with no validation or sensitivity analysis. In this study, micro-simulation modelling of traffic was used to estimate emissions caused by delays at road works, for several traffic management options. The emissions were compared to those created by the maintenance operation, estimated using an LCA model. In this case study, the extra traffic emissions caused by delays at road works are relatively small, compared to those from the maintenance process, except for hydrocarbon emissions. However, they are generally close to, or above, the materiality threshold recommended in PAS2050 for estimating carbon footprints, and reach 5–10% when traffic flow levels are increased (hypothetically) or when traffic management is imposed outside times of lowest traffic flow. It is recommended, therefore, that emissions due to traffic disruption at road works should be included within the system boundary of road pavement LCA and carbon footprint studies and should be considered in developing guidelines for environmental product declarations of road pavement maintenance products and services.

Citation

Galatioto, F., Huang, Y., Parry, T., Bird, R., & Bell, M. (2015). Traffic modelling in system boundary expansion of road pavement life cycle assessment. Transportation Research Part D: Transport and Environment, 36, https://doi.org/10.1016/j.trd.2015.02.007

• Journal Article Type: Article
• Acceptance Date: Feb 15, 2015
• Online Publication Date: Mar 12, 2015
• Publication Date: May 31, 2015
• Deposit Date: Aug 7, 2017
• Publicly Available Date: Aug 7, 2017
• Journal: Transportation Research Part D: Transport and Environment
• Print ISSN: 1361-9209
• Electronic ISSN: 1879-2340
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 36
• DOI: https://doi.org/10.1016/j.trd.2015.02.007
• Keywords: Life cycle assessment, System boundary expansion, Road works, Microsimulation, Pollutant emissions, Sensitivity analysis
• Public URL: https://nottingham-repository.worktribe.com/output/750892
• Publisher URL: https://doi.org/10.1016/j.trd.2015.02.007