PSI - Issue 81

Roman Samchuk et al. / Procedia Structural Integrity 81 (2026) 184–191

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Fig. 1. Overview of the finite element modelling workflow: (a) global model of the crane and runway structure; (b) discrete trolley positions used for load-case generation; (c) runway girder model with column supports and wheel-reaction representation; (d) mesh quality in the web–flange region with an inset showing local refinement.

In the present study, φ 2 = 1 . 27 is applied based on the sti ff ness class HC4 and hoist drive class HD1, while φ 5 = 1 . 5 is used as a baseline representing smooth force changes without significant backlash. Sensitivity to higher values (e.g., φ 5 = 2 and φ 5 = 3) is discussed in Section 3.3.

2.3. Fatigue assessment procedure

2.3.1. Stress evaluation Stress ranges at fatigue-relevant locations in the web–flange region are evaluated from the set of load cases (trolley positions and crane positions). Since weld geometry is not explicitly modelled in the global shell model, the assess ment is performed in a nominal / structural stress sense using corresponding detail categories from the standards.

2.3.2. S–N curves, Detail categories, and Damage accumulation Fatigue verification is based on Palmgren-Miner’s rule using the S–N approach with linear damage accumulation. Detail categories are adopted according to NEN-EN 13001-3-1 (2025) and EN 1993-1-9 (2005) for the considered weld assumptions (double fillet welds and full-penetration welds). Table 2 summarizes the indicative detail category values used in this paper. Fatigue damage is accumulated using the Palmgren–Miner rule, where failure is assumed when D ≥ 1: D = j n j N j , (2)