Research On Sustainability Evaluation And Optimization Of Precast Components Production Based On LCSA

In recent years,due to its advantages in alleviating the contradictions of high energy consumption,serious pollution and low labor efficiency in the construction industry,prefabricated buildings have been vigorously promoted by the government,which has driven the development of precast concrete components and accessories market.With sustainable development becoming the general direction of future development,the theory and tools of life cycle sustainability assessment(lcsa)are becoming more and more mature.The sustainability improvement of the construction industry has also attracted attention,but few people take prefabricated components as the research object.In this context,this study takes the production process of prefabricated components as the research object,applies the lcsa evaluation method to evaluate the sustainability of the production process of main prefabricated components,integrates the sustainability objectives into the optimization objectives,constructs the production optimization model,and puts forward production management suggestions according to the optimization and simulation results,so as to improve the sustainable performance of the construction industry.The following are the research contents:(1)Combing the research background,ideas and contents: through the background,significance analysis and literature review,summarize the current research deficiencies,and sort out the research ideas and contents of this study.(2)Explain the relevant theoretical basis and methods: define the production process and sustainability of prefabricated components studied in this study,as well as the connotation and boundary of production scheduling;Combing the life cycle assessment theory,lean production and other research theories;The main research methods such as lcsa evaluation method,multi-objective function optimization based on genetic algorithm,discrete event modeling and simulation are introduced.(3)Build the lcsa evaluation model in the production stage of prefabricated components: Based on the production process of prefabricated components and the boundary of "from cradle to gate",put forward the quantitative method of production cycle list of prefabricated components production;Based on the literature and expert hierarchy process,the weight system is determined according to the selected impact types,and the LCA,LCC and s-lca evaluation models of prefabricated component production are established in turn;Finally,the LCA,LCC and s-lca evaluation models are aggregated to obtain the lcsa evaluation framework,which provides a basic paradigm and model for the sustainability evaluation of prefabricated component production process.(4)Carry out lcsa evaluation of prefabricated components: select four types of components:interior wall panels,prefabricated stairs,composite beams and composite floors as the evaluation objects.According to the component information collected from the investigation,lcsa evaluation model is applied to evaluate the sustainability of the production of unit volume components,which enriches the existing achievements of life cycle database;The sensitivity analysis of lcsa score is carried out to find the key influencing factors of sustainability,determine their influence direction,and classify them according to the influence size,which lays a foundation for determining the promotion path of sustainability in the production process of prefabricated components.(5)Design the production optimization model and solution algorithm: Based on the analysis of the current situation of workshop production and management,combined with the sensitivity analysis results,analyze the potential path to improve the sustainability of prefabricated component production process,establish the production optimization model with the goal of minimum production energy consumption,on-time delivery and minimum overtime,use the weight coefficient method to combine three objective functions as the fitness function,and design the genetic algorithm to solve the model,An example is used to verify the effectiveness of genetic algorithm,and a sustainable oriented prefabricated component production optimization model and solution are formed,which enriches the existing research results of production scheduling.(6)Production simulation and optimization: The workshop production model is established by Anylogic,the production process of prefabricated components is simulated,the production time of components and the utilization of key resources are analyzed,and the suggestions for improving production management efficiency are provided.Sustainability level differences according to the production process,combined with the enterprise production pressure and order delivery time,design different weightings situation,by using the genetic algorithm to solve the optimal production plan under different situation,analysis the influence mechanism between different sub-goals,and then put forward the reasonable organization to work overtime,moderate production plan scheduling strategies to improve delivery date target weight.According to the simulation and optimization results,further form the prefabricated component factory production to improve the sustainability of the production link and form a scientific suggestion,which is helpful to promote the overall improvement of the management ability of the prefabricated building production link.