چكيده به لاتين
Reviewing the safety of the rail transport network, as an infrastructure part of the economy, is a reflection of the safety level of the entire country's transport network. One of the challenges that threaten safety in the railway network is the condition of railway tunnels in terms of performance and maintenance during the operation period and operational phase. After the operationalization of a tunnel, continuous risk assessment should be carried out as part of the safety management system with the aim of preventing and minimizing risks, because any problem in a tunnel may even paralyze the entire line. As an efficient and effective tool, the risk management system identifies risks and potential conditions for causing accidents and incidents, evaluates them, and after analysis removes or reduces the risk caused by hazards. In this research, the railway tunnels of the Tehran-Tabriz route have been studied. Two methods are introduced to assess the risk level of the tunnels of this route. The first method is the Analytical Hierarchy (AHP) method, which evaluates and prioritizes the risk of tunnels qualitatively. In this method, based on six criteria and five specified options, a pairwise comparison questionnaire was prepared and distributed among nine experts of the General Directorate of Railways of East Azarbaijan province, and by analyzing the output of the questionnaires in the Expert Choice (EC) software, Finally tunnel number 38 was identified as the tunnel with the highest amount of risk, also according to the weight obtained for each of the criteria, the criterion or the risk of collision (with rail vehicles or obstacles) as the most important risk inside the tunnel or options under investigation were selected. Finally, sensitivity analysis was used to rationalize the proposed model and validate it. In the second method, which is William Fine's method, we have two stages, in the first stage, the risk score was scored and prioritized based on the tables related to William Fine's method, in the form of the product of three factors, the probability of occurrence, the amount of contact and the severity or consequence, and High-risk tunnels were placed in three emergency, unnatural and natural levels. Among the considered options, tunnel number 38 with a score of 400 based on William Fine's model again won the title of the most dangerous tunnel. In the second stage of this method, in order to improve the safety of this tunnel, seventeen corrective options were identified, including options that reduce risk or the consequences of risk, and among these options, the justification of eight options in terms of cost and the amount of risk reduction using the William Fine method It was proved.
