The Technique Of Risk Assessment For The Extra-long Highway Tunnel In The Complex Geological Conditions

With the rapid development of road transport, there are more and more tunnelconstruction, for the scal is bigger and bigger, the geological conditions are more and morecomplex, technology demands are increasingly high in design. Meanwhile, the tunnel designprocess has a formation conditions, uncertainties and other characteristics, determines thetunneling process is a complex and volastile, risky large dynamic process. Therefore, in orderto ensure the safety of tunnel construction goals, the need for tunnel construction riskmanagement and risk control. To ensure the security in construction of mountain tunnel, it isnecessary to take a research in mountain highway tunnel construction..As for the inadequate risk assessment and evaluation system in the current design ofmountain highway tunnel at special geological conditions, use engineering research,theoretical analysis, engineering and other methods to carry out mountain highway tunneldesign and application of risk assessment at special geological conditions. Research andresults are as follows:（1）Here are the staff-Mechanical-Environmental-Management system, and on thissystem, do analysis about the mountain highway tunnel construction.like basic meaning ofrisk, risk identification, risk assessment, risk evaluation and other related concepts, at thesame time, introduce the concept of the risk management performance analysis to the risk inmountain highway tunnel design. Then set up a risk assessment pattern of mountain highwaytunnel design.（2）Combination of relevant laws, regulations and norms, extensive data collection onthe basis of the expert survey checklist established by the New Austrian Tunneling Methodmountain road tunnel design safety risk management indicator system. On this basis, theestablishment of the factor system of assessment of the initial risk event risk factors.（3）Based on fuzzy analytic hierarchy process, use expert surveys and the method ofcombining theoretical analysis, establish an easy and strong applicability risk assessmentmodel of mountain highway tunnel design first, evaluate the risky factor of mountain highwaytunnel construction through AHP, quantify the risky factor of mountain highway tunnel designthrough fuzzy Set Theory; then creat a membership function with probability of the riskfactors and occurrence of the consequences combine with fuzzy statistics and experiences ofexperts, provides a set of system method for the implementation of risk assessment ofmountain highway tunnel design.（4）With the Risk Assessment Model of mountain highway tunnel design,do an risk assessment on Liu Pan mountain tunnel. It provide technical support for Engineering designand construction.