Fuzzy Evaluation And Control Of Construction Risk Of Main Tower Cap Of Cross-sea Cable-stayed Bridge From The Perspective Of Group Decision

With the development of China’s infrastructure,more and more cross-sea bridges are being built.Different from roads and other projects,the construction process of the cross-sea bridge is more complicated,with greater investment,longer construction period,and there are more factors need to be considered.There will be a lot of unsafe factors during the construction of the cross-sea bridge.Therefore,it’s necessary to assess and control the construction risk of cross-sea bridges,identify potential risks in advance,improve engineering construction plans,and improve risk control measures.This article takes the construction of the cross-sea bridge platform as an object,and evaluates and studies the risks that may occur in different parts of the platform during the construction process.On the basis of analytic hierarchy,the group judgment theory is used to evaluate and analyze the risk indicators in different levels to determine the probability of risk occurrence for each indicator.The fuzzy comprehensive evaluation is then used to calculate the severity of the construction risk of the cross-sea bridge cap.The main research contents are as follows:(1)Analysis and research on the necessity of bridge construction risk assessment.Through the analysis of relevant literature on the status of domestic and foreign bridge construction risk analysis and research,we understand that the current research on the risk analysis of cross-sea bridge construction needs further in-depth,and it’s necessary to establish a set of construction risk assessment methods suitable for the cross-sea bridge platform,and add group judgment methods to improve on the basis of the existing AHP and fuzzy mathematics.(2)Research on construction risk assessment method of cross-sea bridge cap.By analyzing common qualitative and quantitative risk analysis methods,considering its advantages,disadvantages and scope of application,a fuzzy comprehensive evaluation method combining qualitative and quantitative is given,combined with the particularity of cross-sea bridge construction.(3)Research on fuzzy comprehensive evaluation odel of construction risk of sea-crossing bridges.Expert investigation method is adopted to identify the risk factors of the construction of bridge caps across the sea,and establish a risk assessment model for cross-sea bridge construction to calculate the possibility weight and severity weight of each factor using the analytic hierarchy process,then introduce the group judgment theory to weaken the subjectivity of evaluation results.Finally,the fuzzy mathematics theory is used to determine the membership function of the risk index to calculate the overall risklevel.By establishing risk assessment methods to analysis of actual cross-sea bridge construction cases,and find out what may be significant risk sources during the construction process,then formulate the corresponding risk control measures based on the research results.