A study on carbon dioxide emissions of high-polymer road maintenance technology based on life cycle assessment evaluation

Road repair and maintenance is the foundation for maintaining the health of roads. High-polymer grouting technology is an advanced non-excavation road repair and reinforcement technique. However, there is limited existing research focusing on this material and technique's carbon dioxide emissions and influencing factors. This study aims to elucidate the carbon dioxide emissions in the life cycle assessment of high-polymer grouting repair technology, using the example of maintenance work on semi-rigid asphalt pavement. The solidification reaction of each kilogram of high-polymer grouting material will release approximately 11.82 g of carbon dioxide. Comparative analysis was conducted by juxtaposing the carbon dioxide emissions at various stages of high-polymer grouting technology with those of cement grouting techniques and traditional excavation-based repair methods, encompassing conventional assessment (CA) on fuel combustion of engineering equipment and comprehensive life cycle assessment (LCA) on the materials production, fuel production, traffic delay, and engineering equipment. The results indicate a substantial reduction in carbon dioxide emissions for highway maintenance projects employing high-polymer grouting repair technology. The carbon dioxide emissions were reduced by 76.1% and 87.3% respectively per kilometer. The primary contribution to carbon dioxide reduction is observed during the construction phase and in terms of alleviating traffic delays. An indirect relationship is established between the carbon dioxide emissions of high high-polymer grouting materials and their strength, providing a reference for dynamically selecting material density in maintenance projects. The analysis of potential strategies to reduce CO2 emission in the transport sector and other industrial sectors suggests that the LCA model has the capability to accurately pinpoint the main contributing factors and CO2 emission levels stemming from specific maintenance processes within the intricate transportation system. The emphasis on enhancing the production technology of high-polymer materials is pivotal for further reducing carbon dioxide emissions in the context of high-polymer grouting repair technology.