PSI - Issue 70

Anil Pradeep Konda et al. / Procedia Structural Integrity 70 (2025) 153–160

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6. Double Damage Case To investigate the combined effect of multiple damage mechanisms, identical web cut and weld failure cases, previously analysed separately in Sections 5.2 and 5.3, were introduced simultaneously in a single castellated beam. The results of the corresponding damage assessment are presented in Fig. 7.

Fig. 7: Damage Assessment of Castellated Girder (a) Deflections, (b) Deflection Change and (c) Relative Deflection Change The deflection change plot in Fig. 7(b) clearly shows that the weld failure in the 2m to 3m span also affects the adjacent 3m to 4m span. Before the weld failure, the 0m to 2m span showed negative deflection values, indicating that the 2m to 3m span had already lost significant flexural stiffness. Since this is a double damage case, calculating damage severities involves solving two linear equations using Damage Severity Consistency values before and after the damage. However, the erratic pre-damage values in this case render further calculations counterintuitive, as they would lead to unreliable and physically meaningless results. Consequently, the authors concluded that achieving meaningful results, even approximately, using the employed damage detection method would be challenging in scenarios involving double or multiple damages when weld failure occurs near the supports. 7. Discussion and Conclusions The authors conducted a pilot study to numerically investigate the selection of an appropriate finite element (FE) modelling approach for steel plate girders. The results indicated that both shell and solid elements closely represent the behaviour of plate girders. To assess damage in these girders, the authors employed the damage detection method proposed by Le et al. (2019). As a first step, authors evaluated a single damage case in a steel plate girder with the exact dimensions of the castellated section by introducing a 5 mm cut at the bottom flange. The element damage severity observed in this single damage case exhibited only a 1% difference compared to the castellated girder. After validating through comparison, the authors investigated a weld failure scenario in the castellated girder. In this case, the stiffness reduction in the 2 m to 3 m section due to weld failure was approximately 75%. The authors examined a double damage scenario involving a weld failure and a cut in the bottom flange. It was found that the employed damage detection method became unreliable when applied to multiple damage locations, particularly when complete weld failure occurred near the supports. This study considered only complete weld failure. Future work can explore partial weld failures to assess the method’s efficacy, and alternative approaches may be needed to quantify damage in cases of complete weld failure near supports. Acknowledgements The simulations presented in this work were performed using ABAQUS/CAE licensed to the Indian Institute of Technology Kharagpur under an academic license from Dassault Systèmes. References Anupriya, B., Jagadeesan, K., 2013. Strength study on castellated beam. International Journal of Engineering Research & Technology 2. Bauer, K., 2021. Design of castellated steel beams. Elaiwi, S.S., 2019. Analysis and design of castellated beams.