Green Life Cycle Assessment System And Carbon Emission Calculation Of Building Structures In Extreme Climate Regions

In recent years,with the continuous acceleration of urbanization throughout the country,the increase of a large number of new building structures makes the problems of energy consumption and environmental pollution increasingly prominent,which has seriously affected the sustainable development of the construction industry.At present,the carbon emission of China's construction industry has been at a high level.Compared with other industries,the carbon emission of construction industry is more affected by materials,design,construction,operation and maintenance,so it has a higher emission reduction space.With the popularization of the concept of sustainable development,the development of green building is the first choice to solve the carbon emissions and environmental problems of China's construction industry,and it is also the era requirement of low-carbon society for the development of construction industry.In order to meet the demand of low-carbon emission reduction for the development of green building,this paper mainly studies the whole life cycle green evaluation of building structures in extreme climate areas,including the construction of conventional building structure evaluation system,the construction of building structure evaluation system in extreme climate areas,the construction of carbon emission calculation model of building life cycle and the calculation of carbon emission of new material structure are studied.The main research contents and conclusions are as follows:(1)The green evaluation system of structure life cycle is proposed.According to the characteristics and influencing factors of the whole life cycle of building structure,a four level evaluation index system is proposed in this paper,which includes project,category,item and index.The evaluation contents of each level are elaborated in detail,and the calculation method of each evaluation index is determined.According to the evaluation system,it can lay a foundation for the subsequent green life cycle evaluation of the structure.(2)The green performance evaluation system of building structure under extreme climate conditions is established.Because the extreme climate area may have important energy resources,scientific research,political and military value,the new green evaluation system of building structure under tropical island and low temperature and cold extreme climate conditions is established,and the calculation method of green evaluation index system is modified,which can provide a reference for the green performance evaluation of the structure under extreme conditions.(3)The calculation model of carbon emission in each stage of building life cycle is established.Based on the life cycle assessment(LCA)theory,the building life cycle is divided into four stages: building materials production,construction,operation and maintenance,demolition and recycling.The carbon emission links in each stage of the building life cycle are determined,and the calculation method of carbon emission in each stage of the building life cycle is established.The model can provide a theoretical basis for the carbon emission calculation of building structure.(4)Case analysis of carbon emission calculation in the whole life cycle of building structure.According to the life cycle carbon emission calculation model established above,the carbon emissions of building structures in tropical island climate(frp-ssc),hot summer and warm winter climate(RC structure of traditional reinforced concrete)and cold climate are calculated respectively,The carbon emission characteristics of different building structures in different stages of the whole life cycle are compared and analyzed.The results show that the building materials production and operation and maintenance stage are the two stages with the most carbon emission and energy consumption.The total carbon emission in the operation and maintenance stage accounts for more than 60% of the total carbon emission in the whole life cycle of the building structure,followed by the building materials production stage,with the carbon emission reaching 31%.According to the annual average carbon emission intensity of each stage of building life cycle,the carbon emission intensity of building materials production stage is the highest.In general,the use of green building materials can reduce the carbon emissions of the whole life cycle of buildings and the annual average carbon emission intensity at the same time.At the same time,it is suggested to start the research from the production,operation and maintenance stage of building materials,which accounts for a large proportion,so as to effectively change the energy structure,reduce the energy consumption of building structures,and promote the development of low-carbon green buildings.