Safety Risk Assessment Of Tunnel Construction On The Qinghai-Tibet Plateau

There are many mountains and ridges in the western region,and railway and highway construction will inevitably have to cross mountains and ridges.Tunnel construction has the characteristics of large impact on the surrounding environment,long construction period,and many uncontrollable factors during construction,especially in the face of more complex construction environments and construction for the more difficult areas on the Qinghai-Tibet Plateau,tunnel construction has become a very risky construction project.In order to smoothly promote the construction of tunnels in the Qinghai-Tibet Plateau and prevent safety accidents,it is very important to carry out the safety risk assessment of tunnel construction.Therefore,this paper studies and evaluates the safety risks of tunnel construction in the Qinghai-Tibet Plateau on the basis of studying a large number of relevant documents combined with actual data.The research content is as follows:(1)In order to study the content and method of tunnel construction risk assessment,at home and abroad on the tunnel construction safety risk evaluation,on the basis of literature,the related scholars research results were reviewed,and put forward the problems existing in the field,and elaborates the concept and principle of risk evaluation,on the basis of contrast and master the process and methods of risk assessment.(2)Study the mechanism of tunnel construction accidents,and then type list to collect and analysis the tunnel construction safety accident,this paper sums up the main factors affecting the safety of tunnel construction,and with reference to the interim provisions on railway tunnel risk assessment and management,using the method of risk factor checklist for risk factors affect the safety of tunnel construction,which can identify Based on the man-machine-environment-management system engineering theory,the safety risk factors of tunnel construction in Qinghai-Tibet Plateau region are screened.Finally,according to the characteristics of tunnel construction in Qinghai-Tibet Plateau region,7 first-level indexes and 30 second-level indexes are selected to establish the safety risk evaluation index system of tunnel construction in Qinghai-Tibet Plateau region.(3)According to the certainty and uncertainty of tunnel construction risks in the Qinghai-Tibet Plateau,through the research and comparison of common risk assessment methods,a five-element connection number-based tunnel construction safety risk evaluation model in the Qinghai-Tibet Plateau is finally constructed.The weighting method adopts the combined weighting method based on the AHP method and the entropy weight method,and the final output model adopts the principle of confidence to determine its risk level.(4)In order to verify the suitability of the evaluation index system and the applicability of the evaluation model,this paper selects the Kunlun Mountain tunnel construction in the Qinghai-Tibet Plateau region as an engineering example for verification.Comprehensive connection number formula by calculation and analysis of the index,it is concluded that Kunlun mountain tunnel construction safety risk ratings for Ⅳ overall level,the higher the risk,and analyze the indicators set pair potential and trend of partial connection number,it is concluded that system general state of steady development,and internal indicators show is the same in the,in with the dynamic development trend...