Energy Consumption and Carbon Emissions in Asphalt Pavement Construction: A Lifecycle Assessment of a Modular Approach

Asphalt mixtures are widely used composite materials in pavement engineering, and their evaluation increasingly requires consideration of both functional performance and environmental sustainability. This study develops a modular lifecycle assessment (LCA) framework to quantify energy consumption and carbon emissions as additional performance indicators of asphalt mixtures in China. By standardizing unit processes, the framework integrates raw material production, processing, transportation, and construction, enabling efficient and reproducible evaluation of material-related impacts. Comparative results demonstrate that stone mastic asphalt (SMA) mixtures consume 2.6 times more energy and release 1.6 times more carbon emissions than asphalt concrete (AC) mixtures under identical pavement structures. Raw material production and mixing dominate the environmental footprint, contributing 87 – 96 % of energy use and over half of total emissions, while transportation distances further influence material performance. The proposed modular approach, through parameterized modeling and data reuse, enhances the efficiency and accuracy of environmental assessment. By establishing energy and carbon intensity as measurable attributes of asphalt mixtures, this study expands conventional material evaluation beyond mechanical and durability properties, providing a new perspective for the selection and optimization of pavement materials.