PSI - Issue 42

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ScienceDirect

Procedia Structural Integrity 42 (2022) 1552–1559 Structural Integrity Procedia 00 (2019) 000–000 Structural Integrity Procedia 0 (20 9) 000–000

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© 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the 23 European Conference on Fracture – ECF23 Abstract Parabolic leaf springs have been used in suspensions of two-axle freight wagons. In real operating conditions, freight wagons are subjected to random loadings in longitudinal, lateral and transversal directions. Under these conditions, methods to treat random loadings should be used. Counting methods, such as the rainflow are very common in this type of analysis. In spite of its application, counting methods need too much computing resources, and because of that an alternative method based on the maximum variance (MVM) may be a more e ffi cient method. An analysis based on finite element method together with MVM-based fatigue analysis is considered. The analysis was enriched considering the hardening cyclic model of 51CrV4 steel for the master leaf, the main component at which fatigue crack initiates. The MVM method allowed e ff ectively determining di ff erent points with high potential for fatigue crack initiation for two di ff erent random loading scenarios, when they are compared to the typical fracture surfaces due to fatigue in di ff erent regions of the master leaf. 2020 The Authors. Published by Elsevier B.V. is is an open access article under the CC BY-NC-ND license (http: // creativec mmons.org / licenses / by-nc-nd / 4.0 / ) r-review under responsibility of 23 European Conference on F acture – ECF23 . Keywords: Maximum Variance Method ; Random Amplitude Loading; Critical Plane; Parabolic Leaf Spring; Railway. 23 European Conference on Fracture – ECF23 Determination of the Highest Potential Spots for Fatigue Failure in Parabolic Leaf Springs using the aximum Variance Approach V´ıtor M. G. Gomes a,b, ∗ , Ab´ılio M. P. de Jesus a,b , Jose´ Correia a,b , Rui Calc¸ada a,c a FEUP, Faculty of Engineering of the University of Porto, 4200-465 Porto, Portugal b INEGI, University of Porto, FEUP Campus, 4200-465 Porto, Portugal c CSF, Centre of Competence in Railways, 4200-465 Porto, Portugal Abstract Parabolic leaf springs have been used in suspensions of two-axle freight wagons. In real operating conditions, freight wagons are subjected to random loadings in longitudinal, lateral and transversal directions. Under these conditions, methods to treat random loadings should be used. Counting methods, such as the rainflow are very common in this type of analysis. In spite of its application, counting methods need too much computing resources, and because of that an alternative method based on the maximum variance (MVM) may be a more e ffi cient method. An analysis based on finite element method together with MVM-based fatigue analysis is considered. The analysis was enriched considering the hardening cyclic model of 51CrV4 steel for the master leaf, the main component at which fatigue crack initiates. The MVM method allowed e ff ectively determining di ff erent points with high potential for fatigue crack initiation for two di ff erent random loading scenarios, when they are compared to the typical fracture surfaces due to fatigue in di ff erent regions of the master leaf. © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of 23 European Conference on Fracture – ECF23 . Keywords: Maximum Variance Method ; Random Amplitude Loading; Critical Plane; Parabolic Leaf Spring; Railway. 23 European Conference on Fracture – ECF23 Determination of the Highest Potential Spots for Fatigue Failure in Parabolic Leaf Springs using the Maximum Variance Approach V´ıtor M. G. Gomes a,b, ∗ , Ab´ılio M. P. de Jesus a,b , Jose´ Correia a,b , Rui Calc¸ada a,c a FEUP, Faculty of Engineering of the University of Porto, 4200-465 Porto, Portugal b INEGI, University of Porto, FEUP Campus, 4200-465 Porto, Portugal c CSF, Centre of Competence in Railways, 4200-465 Porto, Portugal

1. Introduction 1. Introduction

Over time, the rail industry has been demonstrating its ability to combat climate change and global warming. Because of its enormous potential, European countries have been investing in the passenger and freight sectors. In the freight rail sector, demand has increased in recent years, resulting in increased operational frequency. As one might expect, the more freight wagons are used, the more likely will be the problems. As a result, freight wagon availability decreases, and economic compromises may not be reached. The fatigue phenomenon that occurs at leaf springs is one cause of the lower availability of those vehicles. Despite prior knowledge of leaf spring fatigue, the problem in the railway sector persists. Then, there is still a gap in knowledge about the health of the leaf spring that needs to be filled. Over time, the rail industry has been demonstrating its ability to combat climate change and global warming. Because of its enormous potential, European countries have been investing in the passenger and freight sectors. In the freight rail sector, demand has increased in recent years, resulting in increased operational frequency. As one might expect, the more freight wagons are used, the more likely will be the problems. As a result, freight wagon availability decreases, and economic compromises may not be reached. The fatigue phenomenon that occurs at leaf springs is one cause of the lower availability of those vehicles. Despite prior knowledge of leaf spring fatigue, the problem in the railway sector persists. Then, there is still a gap in knowledge about the health of the leaf spring that needs to be filled.

∗ Corresponding author. E-mail address: vgomes@inegi.up.pt ∗ Corresponding author. E-mail address: vgomes@inegi.up.pt

2452-3216 © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of the 23 European Conference on Fracture – ECF23 10.1016/j.prostr.2022.12.196 2210-7843 © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of 23 European Conference on Fracture – ECF23 . 2210-7843 © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of 23 European Conference on Fracture – ECF23 .