| With the continuous As the Chinese economy continues to develop in a stable and stable manner,the per capita car ownership of the city is increasing year by year,the urban traffic congestion is becoming more and more serious,and the urban land resources are limited,making it difficult to broaden the existing roads or build new roads.How to meet people’s daily travel requirements has become an urgent problem.The subway has many advantages such as large passenger capacity,efficient transportation,energy saving and environmental protection,small environmental impact,and low land use.It provides a new way of travel,which improves the city’s traffic structure and alleviates the increasingly severe traffic in the city.The congestion problem has gained rapid development.However,since the subway project belongs to the underground project,there are many unfavorable factors such as complex internal structure,complicated external environment,complicated construction technology,and difficult working conditions in the construction process,and once the construction project safety accident occurs in the subway project,it usually affects huge losses.Therefore,the field of construction risk management of subway projects has always been the focus of experts and scholars.Based on the construction risk management theory of subway projects,this paper analyzes the construction risk coupling and system dynamics(SD)simulation of subway projects.The main research work is as follows: :(1)Introduce the meaning and characteristics of subway construction risk,the connotation of risk coupling,systematically expound the definition of subway construction risk coupling,and the mechanism of subway construction risk,the elements of transmission,and the types of subway construction risk coupling.A detailed discussion has been made.(2)Based on the subway construction risk management theory,the subway construction risk coupling system is divided into four subsystems: human risk factors,mechanical equipment risk factors,management risk factors and environmental risk factors.On this basis,the types of risk coupling of subway construction are analyzed,and the coupled causal relationship of homogeneous single factor risk,the coupled causal relationship of heterogeneous single factor risk,and the coupled causality of heterogeneous multi-factor risk are discussed.Based on the risk-coupling causality,a subway construction risk coupling evaluation index system including human,machine,ring and tube is constructed.The related methods and concepts of measuring risk coupling are introduced.The method of analytic hierarchy process(AHP)and entropy weight method are used.Combining the weights,using the basic principle of the inverse cloud model to accurately calculate the numerical characteristics of the indicators,and combining the coupling degree function to establish the construction risk coupling model of the subway project,so as to measure the coupling degree of the risk factors of the subway construction.(3)Using Vensim system dynamics software,carry out simulation research on a construction section of Qingdao Metro X line,combining the combined weights given by AHP-entropy weight method with the coupling coefficient calculated by coupling model,for human-machine-ring-The risk coupling system is dynamically simulated,and the overall risk level of the system is analyzed as().By moderately adjusting the coupling coefficient in the system,it is found that(the part has the greatest impact on the risk,and secondly which factor,and the key coupling factor is.According to the decoupling idea,the corresponding risk prevention and control measures are proposed from the front,middle and late stages of risk coupling,which provides reference and reference for improving the risk management level of subway construction. |
