PSI - Issue 77

Christian J. Silva et al. / Procedia Structural Integrity 77 (2026) 631–638 Silva et al./ Structural Integrity Procedia 00 (2026) 000–000

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optimisation to achieve balanced performance. 4. Conclusions

In this work, a finite element model was developed to perform explicit dynamic crash simulations of a railway coach. Through this approach, a comprehensive crashworthiness analysis was successfully carried out, enabling the assessment of structural behaviour under a head-on collision scenario. The simulations allowed the identification of possible failure regions within the baseline structure, providing valuable insight into areas most susceptible to local stress concentrations and plastic deformation. Based on these observations, a modified structure was studied with the objective of mitigating failures and improving overall safety performance. A comparative evaluation of the baseline and modified designs was performed with respect to key parameters defined in European regulation EN 15227, namely survival space preservation and structural deceleration. It was obtained that the modified structure achieved an improvement in the survival space criterion, by halving the maximum reduction in length on passenger survival spaces to a value within the normative limit. However, this result was accompanied by higher deceleration levels. Despite both designs surpassing the normative deceleration limit, the maximum value of mean deceleration for the modified design increased 23 % when compared to the original structure, reflecting the increased rigidity resultant from the design modifications. These findings confirm the value of FEM crash simulations in supporting early-stage failure analysis, guiding design improvements, and contributing to the development of safer railway vehicles in line with certification requirements. Also, it was confirmed that compliance with all normative criteria requires careful optimisation of vehicle structures. Acknowledgements This work is a result of Agenda “Produzir Material Circulante Ferroviário em Portugal”, operation code 02-C05 i01.02-2022.PC645644454-00000065, financed by the Recovery and Resilience Plan (PRR) and by European Union – NextGeneration EU. References Altair Engineering, Inc., 2025. Radioss User Guide. Retrieved from: https://2025.help.altair.com/2025/hwsolvers/rad/index.htm. CEN, 2020. EUROPEAN STANDARD EN 15227:2020 Railway applications - Crashworthiness requirements for rail vehicles. CEN, 2018. EUROPEAN STANDARD EN 15663:2017+A1 Railway applications - Vehicle reference masses. Gao, G., Wang, S., 2019. Crashworthiness of passenger rail vehicles: a review. International Journal of Crashworthiness 24, 664–676. https://doi.org/10.1080/13588265.2018.1511233 Lopes, R., Ramos, N. V, Cunha, R., Maia, R., Rodrigues, R., Parente, M.P.L., Moreira, P.M.G.P., 2023. Coach crashworthiness and failure analysis during a frontal impact. Engineering Failure Analysis 151. https://doi.org/10.1016/j.engfailanal.2023.107369 Molatefi, H., Azizi, M., Mozafari, H., 2016. Crashworthiness analysis and energy absorption enhancement of a passenger rail vehicle. International Journal of Railway Research 3. Murugesan, M., Jung, D.W., 2019. Johnson Cook material and failure model parameters estimation of AISI-1045 medium carbon steel for metal forming applications. Materials 12, 609. Xie, Suchao, Du, Xuanjin, Zhou, Hui, Wang, Da, Feng, Zhejun, 2019. Analysis of the crashworthiness design and collision dynamics of a subway train. Proc Inst Mech Eng F J Rail Rapid Transit 234, 1117–1128. https://doi.org/10.1177/0954409719880770 Zhu, T., Xiao, S.-N., Hu, G.-Z., Yang, G.-W., Yang, C., 2020. Crashworthiness analysis of the structure of metro vehicles constructed from typical materials and the lumped parameter model of frontal impact. Transport 34, 75–88. https://doi.org/10.3846/transport.2019.7552