Research On Benefit Assessment Of Embodied Energy In Precast Concrete Construction

With the development of the construction industry,its increasingly prominent problems such as high energy consumption and high pollution,have gradually become the most important obstacles to the development of China's construction industry.Since 1978,China's former State Construction Committee proposed the goal of industrial construction in the planning meeting of the construction industrial,the construction industry in China has kept drawing on the successful experience of developed countries such as the United Kingdom,Japan and other countries,we combined it with China's specific circumstances,made practice on the prefabricated construction and made some achievements.However,in practical application,the efficiency of the assembly structure cannot be scientifically evaluated due to the lack of perfect standard system,and this resulted in the high cost of implementation and the scale effect cannot be achieved.Therefore,in order to further promote the improvement of the national construction benefit evaluation system,and to arouse enthusiasm of the government,developers,construction enterprises and the owners to implement the prefabricated concrete structure,this paper makes some research on the benefit assessment of embodied energy in precast concrete construction.Firstly,the theory of benefit assessment of embodied energy in precast concrete construction is analyzed.On the basis of the definition of prefabricated concrete structure,this paper compares the prefabricated concrete structure with cast-in-place concrete structure,and proposes the concept of benefit of embodied energy in precast concrete construction,which showes as resource consumption efficiency,energy consumption efficiency and Greenhouse effect potential.Based on it,this paper makes compare on the energy consumption during the resource production,material transporting,and construction site of the prefabricated construction products and cast-in-place concrete structures,through which this paper puts forward the advantages and disadvantages of the concrete structure energy problems and the embodied energy assessment at this stage.Then,through the study of relevant literatures at home and abroad and the research of prefabricated concrete structure projects in China,seven evaluation indexes are extracted according to the three aspects of material consumption,energy consumption and carbon gas emission.The comprehensive evaluation index system of energy consumption efficiency of prefabricated concrete structure is established on the basis of the definitions of each index.In this paper,based on the government "Thirteen five Planning" about building energy-saving emission reduction targets,target distance method is used on the weight of the indicators.In the comprehensive evaluation,the theory of set pair analysis is introduced,and the SPA comprehensive benefit evaluation model is established.Through the calculation of the entropy to carry out the comprehensive benefit evaluation,the benefit level of the individual project is obtained,and the improvement method is put forward by analyzing the scores of each item.Finally,the actual prefabricated concrete structure is cited,and the actual project is evaluated according to the energy consumption benefit evaluation model established in the above,and the benefit level is obtained.By comparing the level with the standard,the conclusion of the evaluation is put forward and reasonable suggestions and improvement measures are put forward.