Carbon Dioxide (CO2) Emissions associated with traffic delay emphasized in recent studies has been regarded as an important contributor to the total CO2 emissions of highway pavement maintenance work activities. Nevertheless, CO2 emissions related to the production phase of fuel or energy used by vehicles under traffic delay are rarely considered into CO2 emissions calculation of maintenance work activities, especially in a level of the whole pavement service life. Aiming to estimate the embodied CO2 emissions from maintenance work activities in the life cycle of highway pavement and provide a comprehensive understanding of the contribution of cleaner materials and fuel usage to the CO2 emissions mitigation of highway pavement maintenance, this study firstly developed a practical vehicle activity-based calculation method of CO2 emissions caused by traffic delay. Then integrated this calculation method into Life Cycle Assessment on the CO2 emissions of highway pavement maintenance work activities. Taking an actual freeway flexible pavement with 15-year design life in Shaanxi Province, China as a case study, the direct CO2 emissions from construction machinery and vehicles disturbed by maintenance work activities and embodied CO2 emissions from materials production, fuel production consumed by construction machinery and the disturbed vehicles travelling through the work zone has been calculated. The findings indicate that the totally fuel production related CO2 emissions about the machinery/equipment on site construction and the traffic interrupted by the work zone is 1787.4 ton, nearly accounts for one quarter of the CO2 emissions during the service life of the case freeway pavement, even could match with the CO2 emissions from materials production which is highly emphasized in previous studies. In addition, about 41% of vehicle CO2 emissions are related to the micro vehicle operating situations of speed acceleration and deceleration.

CICTP