The Carbon Footprint Evaluation Of Buildings Based On BIM

With the development of the society, environmental problems are becoming more and more serious. The climate change caused by the greenhouse effect has become more and more obvious. How to reduce the emission of greenhouse gas has become a problem to be solved urgently in the world. In order to measure the reduction of greenhouse gas emission effectively, a variety of greenhouse gas measurement methods have been established, and the carbon footprint method has been widely used in the world.The construction industry is a high energy consumption, high carbon emission industries, whose greenhouse gas emissions count 1/3 of the total emission in the world. The greenhouse gas emissions from the building construction phase is about 18% of the total life cycle, but the research on the carbon footprint of this stage is not in-depth.In order to calculate the carbon footprint of building construction phase rapidly, this paper sum up the carbon footprint of building construction phase into three sources:carbon footprint of building materials, carbon footprint of construction machinery, carbon footprint of transport. By doing research on the construction site, this paper updated the transport carbon footprint factor database, created a new calculation method for transport carbon footprint, and established rapid evaluation model of carbon footprint of building construction phase. By studying how to obtain bill of quantities by using BIM technology and the method of "construction consumption quota", this paper applied BIM technology and computer technology to the carbon footprint evaluation, which made carbon footprint data sources clearly, and made the carbon footprint evaluation more systematized and more standardized, then, "Building Construction Carbon Accounting System" was developed for the study.Finally,15 cases will be studied by using the system, the difference of the carbon footprint of building construction phase between the North and South will be analysis. The results show that the carbon footprint proportion of the building materials, construction machinery and transportation were 94.2% and 4.7%,1.1%. The building materials carbon footprint levels from the South are higher than the North, but the construction machinery carbon footprint levels are lower than the North, the difference of carbon footprint of transport between the South and North are little.