Study On The Optimization Of Green Retrofitting Schemes For Existing Residential Building

With the acceleration of Chinese urbanization process,the area of existing building is more than 64 billion square meters,while the area of green building is only 460 million square meters.Many existing buildings are difficult to meet the growing needs of people in terms of safety performance,resource saving,living comfort and livability.Because there is a large stock of existing residential buildings,which benefit people’s livelihood,it is increasingly significant to carry out green retrofitting of these buildings.China is vigorously promoting the green retrofitting of existing residential buildings,and related technologies are also constantly developing and updating.Starting from the transformation objectives,paying attention to the benefits of living comfort and resource saving of existing residential buildings,and comprehensively considering the factors of technology,economy,environment,society,etc.,to achieve the purpose of the optimization of green retrofitting schemes,it is of great theoretical and practical significance to carry out the research on optimization of green retrofitting schemes for existing residential building.On the basis of the research status of optimization of green retrofitting schemes for existing residential building,this paper summarizes and compares the indexes of relevant standards at home and abroad from the aspects of energy,water resource and material conservation,ecological quality and environmental protection,comfort and livability,economic,social benefits and so on.Based on national standards,the optimization index system of green retrofitting schemes for existing residential building was formed with 6 first level indexes and 15 second level indexes.The purpose of optimization of green retrofitting schemes for existing residential building is to select the most valuable scheme from multiple alternatives.Many indexes have fuzziness when retrofitting schemes are optimized.This paper combines value engineering method and intuitionistic fuzzy mathematics to form IFVE method.In this method,the function coefficient and value coefficient of value engineering are intuitionistically fuzzed,and the intuitionistic fuzzy judgment matrixes of indexes and schemes are established by pairwise comparison.The consistencies of the intuitionistic fuzzy judgment matrix are tested and modified,the intuitionistic fuzzy weight and function coefficient of the index were determined,and the life cycle cost and intuitionistic fuzzy value coefficient of each scheme were calculated.Through the similarity function,the ranking of intuitionistic fuzzy value coefficient was obtained by comparison,and the scheme with large value coefficient was better.A green retrofitting project of existing residential buildings was selected as the case.The index intuitionistic fuzzy weights were calculated to determine through the results of the questionnaire survey.Three alternatives were pairwise compared based on each indicator,and then the intuitionistic fuzzy function coefficients of the alternatives were calculated combining with index weights.The life cycle costs of alternatives were estimated by querying relevant data,and then the cost coefficients were calculated.The intuitionistic fuzzy value coefficients of alternatives were calculated.Through the similarity function,the ranking of intuitionistic fuzzy value coefficient was obtained by comparison.By the analysis of the optimization results,the advantages and disadvantages of each scheme were pointed out.The optimization index system method can provide reference for the design and optimization of similar existing residential buildings.