Research on Key Influencing Factors of Energy Consumption and Carbon Emissions of Asphalt Pavement Based on Generalized Life Cycle

In this study, the existing methods for calculating energy consumption and carbon emissions are reviewed. Afterwards, a generalized life cycle approach is proposed to calculate carbon emissions and energy consumption of asphalt pavement by considering the maintenance and repair processes. Besides, by taking into account of the differences in maintenance methods that affect the road life, annual carbon emissions and energy consumption are suggested as metrics for the measurement of carbon emissions and energy consumption. On this basis, 12 projects with different road surface structures and regions are uniformly selected nationwide. This study deeply explores the energy consumption and carbon emissions of asphalt pavement from the impacts of calculation boundary, environment, construction, and energy-saving and emissions-reduction technology impacts. According to the results, annual energy consumption and carbon emissions of asphalt pavement are greatly affected in the maintenance and repair process, with the maximum annual differences of 37% and 41%, respectively. As indicated by the Spearman correlation analysis road surface structure has a remarkable impact on energy consumption and carbon emissions, and reasonable road surface design should be emphasized in the future road design. Furthermore, by comparing with the hot mix asphalt technology, the emulsified asphalt cold recycling technology can decrease energy consumption and carbon emissions by at least 50%. This study provides theoretical support for the future asphalt pavement structure design, as well as the emissions reduction technology promotion and application of the emissions reduction technology.