Tornado-induced risk analysis of railway system considering the correlation of parameters

The Yangtze River Delta region in China is characterized by a highly dense railway network, coupled with the frequent occurrence of tornado hazards. While tornadoes pose operational risks to railway networks, there was a noticeable dearth of research in this area. To bridge this gap, we propose an analytical framework. Initially, within regions covered by an extensive railway network, we utilize historical data to construct the random field of tornado hazards. For establishing this random field, we recommend adopting the C-vine copula model to capture the correlations among tornado parameters. Subsequently, in the risk analysis of the railway system, three representative disaster scenarios were formulated to comprehensively depict the influence of tornadoes on train operations. Methodologies were presented for calculating the probabilities of these scenarios and the damage measures for train disruption and deceleration. Finally, the physical and functional risk of the railway segments are calculated, and a comprehensive risk assessment is derived. The results reveal that the Angting–Zhengjiang line faces a notably high functional risk, leading to an annual average increase of 0.27 days in the total travel time of the rail network. Both the Angting–Zhengjiang and Yangzhou–Haian lines share the top position in comprehensive risk, emphasizing the need for focused attention.