Investigation and prioritization of risk factors in the collision of two passenger trains based on fuzzy COPRAS and fuzzy DEMATEL methods

Identifying the critical risk factors in train accidents play a vital role in the prevention of their recurrence in the future. However, this is a complex procedure due to the fact that it includes decision making and depends on a large number of relevant factors. In order to resolve this problem, first, this study made an effort to identify the risk factors in the collision of two passenger trains near the ‘‘Haft Khan Station’’ between Semnan and Damghan using the interview technique and the questionnaire survey technique which focused on railway industry experts’ opinions and treated them as decision makers. Second, it developed a new framework of risk assessment by prioritizing the identified risk factors in the collision of two passenger trains in order to remedy all of the deficiencies and to improve the safety of railway transportation. Therefore, risk assessment of contributory factors in the collision was based on multi-criteria decision-making approaches such as fuzzy complex proportional assessment (COPRAS) and fuzzy decision making trial and evaluation laboratory (DEMATEL). Accordingly, the study prioritized the risk factors in the collision of two passenger trains including management, individual and environmental conditions, and reaction to events regarding Fuzzy COPRAS and Fuzzy DEMATEL. Finally, sensitivity analysis indicated that the fuzzy DEMATEL had a better performance than the fuzzy COPRAS method. More specifically, it: (a) prioritized the risk factors in a better way due to its higher Spearman’s ranking correlation coefficient; (b) facilitated the cause-effect analysis; and (c) was in line with the real collected observation data. In regard to Fuzzy DEMATEL model, the results showed that the critical risk factor with the highest rank was the stop of the front train at the back of the hill. Moreover, the critical risk factor with the lowest rank was the absence of the installation of the Balise system.