Life Cycle Sustainability Assesment Of Prefabricated Buildings

In the traditional extensive construction site,there is a large amount of earthwork and a lot of wet work.Many construction steps are completed by hand.The construction efficiency is low and it causes considerable dust and noise pollution.At the same time,the degree of aging in China continues to deepen.The reduction in the supply of labor brought about by the aging of the population has a direct impact on the construction industry,and it is imminent to accelerate the upgrading of the construction industry.The prefabricated construction method has the characteristics of reducing environmental pollution and saving resources while improving labor productivity and construction level.However,the environmental and social benefits of prefabricated buildings have not been fully recognized by society.The high incremental cost has led developers to be reluctant to develop it,and consumers have not fully realized the advantages of prefabricated buildings.Most of the discussions on the current environment and economic benefits of prefabricated buildings stay in qualitative analysis,and they are not considered from the perspective of the entire life cycle.The environmental and economic benefits brought about by the good building performance of the prefabricated building during use,and the quantitative research on the social benefits of prefabricated building is even more lacking.Therefore,it is necessary to comprehensively and quantitatively analyze and evaluate the prefabricated buildings from the three dimensions of environment,economy and society to determine their life cycle performance.This paper applies the theoretical method of Life Cycle Sustainability Assessment(LCSA),combined with the construction characteristics of prefabricated buildings,clarifies the boundary of the life cycle scope of prefabricated buildings,and proposes a quantitative method of prefabricated building life cycle inventory.And established the assessment model of life cycle environmental impact,life cycle cost,life cycle social impact of prefabricated buildings,and integrated these three models into prefabricated building life cycle sustainability evaluation system.Then standardize it into the life cycle sustainability evaluation index,and use AHP to calculate the weight of each index.Applying the above evaluation model,this paper selects two high-rise concrete residential buildings with the same plane,the same area and the same number of floors,which are built using the assembly and cast-in-place construction methods.The three dimensions included in its life cycle sustainability are quantitatively analyzed,and the analysis results are compared to obtain a quantitative comparison result of the life cycle sustainability of prefabricated buildings and cast-in-place buildings.The results show that the LCSA index score of 60.81 for prefabricated buildings is better than the LCSA index score of 49.75 for cast-in-place buildings.The life cycle sustainability of prefabricated buildings is significantly better than cast-in-place buildings.