PSI - Issue 42

Vítor M. G. Gomes et al. / Procedia Structural Integrity 42 (2022) 1552–1559 V.M.G. Gomes et al. / Structural Integrity Procedia 00 (2019) 000–000

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of these spots was found by implementing an optimization algorithm, which determines the critical plane where the resolved shear stress is maximum. The numerical model included an elastoplastic analysis for the master leaf and elastic for the rest of the components. Combined hardening was introduced with parameters estimated by the monotonic properties of 51CrV4 steel. Regarding the boundary conditions attributed to the model, these took into account the actual fixation of a parabolic leaf spring in a two-axle freight wagon, as well as the imposed random displacement. Two scenarios for the imposed displacement were considered for analysis. From the application of the maximum variance method to the two scenarios under analysis, the following main remarks can be enumerated: • The places of greatest variation were created for both scenarios in the middle zone of the leaf spring. However, when an initial lateral displacement is applied (scenario 2), a potential for failure at the ends where the fibers are most active is verified; • Greater variability in the value of the amplitude of the vertical and lateral displacements (scenario 1) induces a greater potential for failure in the central zone of the notch. However, the same result for scenario 2, whose the variability of the components of lateral and vertical displacement is lower was not verified; • The zones closest to the fixing supports are almost symmetrical across the leaf width in both scenarios. Moreover, the maximum value of the variance of the resolved shear shears appears to occur at nearby of x = -60 mm and x = 60 mm. Additionally, significant changes do not exist between the two scenarios and this may conduct to the conclusion that the maximum value of the resolved shear stress will be influenced mainly by the vertical oscillation of the load.

Acknowledgments

The authors thank to MEDWAY (Maintenance and Repair), AI0181 - Research Project - FERROVIA 4.0 - POCI 01-0247-FEDER-046111, doctoral programme iRail- Innovation in Railway Systems and Technologies funding by the Portuguese Foundation for Science and Technology, IP (FCT) through the PhD grant (PD / BD / 143141 / 2019). Also, a thank you to the Python, Julia, and Ansys community.

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