Risk Management For Subway Tunnel Consturction Based On System Dynamics

With the continuous development of economy in our country,the subway as a member of the important in modern transportation,subway construction has been rapid development,however the subsequent construction accident problem has aroused people's more and more attention,because once a safety accident in construction stage,its influence not only on economy,brings the huge losses,workers' life safety and social effects would have lasting consequences.As the subway tunnel construction system is a complex dynamic system,there is continuous feedback of multiple information in the system,showing the characteristics of dynamic,complex and multiple feedback,so it is suitable to use the method of system dynamics for research.Based on the research method of system dynamics,this paper divides the risk system into three subsystems of man,excavation support and measurement to analyze the risk management of subway tunnel construction in detail.The system dynamics theory and method are used to build the system dynamics model with specific engineering examples to simulate the overall risk level of subway tunnel construction.Through adjustment of different schemes,the future risk level of the system is predicted intuitively,providing a theoretical basis for risk management.The main research work and content of this paper are as follows:(1)A systematic study was conducted on the safety risks of subway tunnel construction,and the risks were divided into three categories: human factor risk,excavation support factor risk and measurement factor risk.In addition,the risk of human factors was emphatically analyzed and discussed.By constructing the SD model of the human factors subsystem,the interaction between different factors on the human factors system and the degree of influence on the human factors system were obtained.(2)Through 4M1 E management theory and identification method of safety accident influencing factors,hazard sources in subway tunnel construction process are identified,a subway tunnel construction risk factor system is constructed,and analytic hierarchy process is used to calculate the influence weight of each risk.(3)Based on the theory and method of system dynamics,this paper analyzes the causal relationship,gives the causal relationship diagram,and establishes the flow potential flow rate,variable set and system dynamic equation according to the causal relationship diagram,and draws the system flow diagram of the construction risk of subway tunnel.In the end,the risk level of the subway tunnel construction system is predicted against the background of the interval between shaozitang and chigangling station in the second section of the no.4 rail transit line in changsha,and the specific risk avoidance measures are proposed based on the simulation results.