Research On Assessment And Control Of Prefabricated Building Construction Safety Based On Catastrophe Theory

In recent years,with the development of building industrialization,prefabricated building as a new building has been vigorously promoted.Compared with the traditional building,the construction process of prefabricated building is more energy-saving and environmental protection,the construction speed is faster,and can maximize the "four sections and one environmental protection" characteristics,not only can effectively shorten the construction period,but also improve the scientific content of the construction industry.In order to make the prefabricated building develop continuously,the safety management of its construction must be solved.At present,the construction safety evaluation system for traditional buildings has been more mature,but as a new type of building,the theoretical research on its safety needs to be developed.Construction project construction system is a complex and open self-organizing system.Safety accidents often occur suddenly in the construction process,so catastrophe theory can be used to study the catastrophe point.Firstly,through the analysis of the characteristics of prefabricated building construction,summarizes the hazard sources of prefabricated building,defines the meaning of safety evaluation,analyzes the existing safety evaluation methods and characteristics,analyzes the reasons for the use of catastrophe theory,and introduces catastrophe theory and fuzzy mathematics in detail.Secondly,according to the selection basis and principle of evaluation index,according to the construction characteristics of prefabricated building,the evaluation index system of prefabricated building safety is established.Because the economic significance of each index is different from each other,it is not comparable,so the expert assignment method is used to quantify each index,and a safety checklist is designed for the experts to score.Thirdly,according to the catastrophe characteristics of prefabricated building construction safety,the catastrophe state of prefabricated building construction safety system is divided into "human factor" and "material factor" catastrophe,and the unsafe behavior of human and the unsafe state of material are taken as two control variables,and the system,i.e.prefabricated building construction safety degree,is taken as state parameter.The cusp catastrophe model is selected to analyze the evolution of safety catastrophe mechanism of prefabricated building construction.According to the characteristics of construction safety evaluation index of prefabricated building,Cauchy distribution is selected as fuzzy membership function to dimensionless the bottom index.After normalization operation,the total fuzzy mutation membership function is integrated with the principle of"complementarity" and "non-complementarity" to judge the construction safety of prefabricated building.Grade.Taking an prefabricated project in Nanjing as an example,the validity of the safety evaluation method is verified,and the measures to improve the construction safety of the prefabricated building are put forward.Finally,the construction safety optimization control model of prefabricated building is constructed,and the model is optimized according to the case of Nanjing assembly project.According to the characteristics of the model,the LINGO software is used to solve the model.The counter measures and suggestions for improving the safety of prefabricated building construction are summarized.The research shows that the fuzzy catastrophe theory can reasonably describe the accident mechanism of the prefabricated construction safety system,and can realize the prediction of the system safety state in the construction process.The research results provide a new idea for the safety management of prefabricated building construction,and enrich the research content of prefabricated building construction safety system to a certain extent.