地铁轨道工程全生命周期碳排放评估及动态分析OA

[Objective]In the process of actively promoting the strategic goals of"carbon peaking and carbon neutrality"in China,the assessment and optimized reduction of carbon emissions throughout the life cycle of rail transit have become important research directions.[Methods]Taking a certain line of Nanjing Metro as a case study and based on the theory of life cycle assessment(LCA),this study proposed a carbon emission calculation model for metro track engineering covering the materialization,construction,and maintenance phases.Furthermore,a dynamic analysis model was established to predict future changes in carbon emissions during the maintenance phase.[Results]The results indicated that the life-cycle carbon emissions of the Nanjing Metro case were approximately 65 179.34 tCO2,with 34.11％of emissions occurring during the materialization phase,41.90％during the construction phase,and 23.99％during the maintenance phase.During the materialization phase,carbon emissions mainly originated from the production of steel rails and precast track slabs(more than 95％),while carbon emissions during the construction phase were mainly associated with the use of building materials(more than 70％).Although the proportion of carbon emissions during the maintenance phase was relatively low,the cumulative effects of equipment renewal and major track overhauls could not be ignored.Moreover,with the application of low-carbon technologies and the optimization of the energy structure,future track engineering showed enormous potential for carbon emission reduction.Optimizing steel smelting processes,adopting low-carbon building materials,and introducing more efficient construction and maintenance equipment were effective approaches to reducing life-cycle carbon emissions.[Conclusion]The research findings provide a new method for the systematic assessment of carbon emissions throughout the life cycle of rail transit projects,which can be widely applied to carbon emission assessment of track engineering in different rail transit systems.This method offers an important theoretical basis for promoting the green and low-carbon transformation of the industry.