Risk Assessment Of Tunnel Engineering Design Based On Bayesian Network

With the rapid development of science and technology and economy,China's traffic infrastructure construction investment is increasing.Tunnel engineering is an important part of traffic road,which seriously affects the safety and economy of road construction,and has become the focus of road construction risk management.Risk assessment is the most effective means to control the risk of tunnel construction,especially in the design stage.However,the traditional design risk assessment method has some defects,such as strong subjectivity,lack of correlation analysis between risk elements,rough assessment results and so on.Therefore,how to use advanced science and technology to carry out efficient,economic and reliable risk assessment of tunnel construction has become one of the hot issues.This paper takes the collapse risk assessment of Lancang tunnel as an example to carry out the risk assessment of tunnel engineering.Firs tly,through literature analysis and expert investigation,the risk factors of tunnel construction are summarized,and ISM method is used to analyze the interaction between the factors and build the risk chain.Combined with expert investigation method,th e uncertainty reasoning model of multi factor comprehensive impact risk events is established;Then it analyzes the influencing factors of collapse risk in the process of tunnel construction and design,determines the influence degree of each factor on tun nel construction and their relationship,and establishes ism interpretation structure model;Finally,the dynamic prediction model of tunnel construction risk is constructed to realize the quantitative assessment of collapse risk in Lancang tunnel construc tion.The conclusions and values are as follows:(1)The tunnel risk prediction based on Bayesian network can make the interaction between various elements clear,the formation mechanism of risk events further clear,and the analysis results are more objec tive and reliable.Therefore,it has a good application prospect in the field of tunnel design risk management.(2)Because the causative mechanism of various risk events in tunnel engineering is stable,the tunnel risk assessment model based on Bayesian n etwork can be used repeatedly and optimized continuously without re modeling and assessment for different tunnels each time.(3)The forward analysis of the tunnel design risk prediction model based on Bayesian network can quickly solve the tunnel design r isk,and the reverse analysis can quickly find out the risk factors of the tunnel design risk,and comprehensively analyze the effect of different design optimization measures on reducing the risk.Based on this,dynamic early warning of tunnel design risk can be realized,and effective guidance can be provided for tunnel design risk assessment and control.