Quantitative analysis and characteristic study of carbon emission in expressway construction period
The process of expressway construction is divided into three stages:material production,material transportation and construction.The carbon emission accounting model of each stage of expressway construction is constructed by using carbon emission factor method.The Qin-Tang Expressway is taken as the research object for quantitative analysis.The cal-culation results show as follows:The total carbon emission and carbon intensity during the construction period of Qintang Expressway are437 200 t,15 800 t/km,and the proportion of carbon emission at each stage is 91.51%,7.81%and 0.68%,respectively;The highest carbon emission in the material production stage is 400 000 t,and the carbon emission intensity is 14 400 t/km,among which the production and processing of cement and steel are the key to the carbon emis-sion in the material production stage of expressway;In all unit projects,more than 80%of carbon emissions come from cross engineering,bridge and culvert engineering and roadbed engineering,among which cross engineering carbon emis-sions are the largest,accounting for 36.84%of the total projects.