PSI - Issue 19

Sandro Citarelli et al. / Procedia Structural Integrity 19 (2019) 336–345 Sandro Citarelli, Markus Feldmann / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 3. Weld execution (double-bevel groove weld)

Fig. 4. Weld execution (single-bevel groove weld)

Fig. 5. Exemplary macrosection

2.2. Loading condition

During their service life, the crane runway girders have been subjected to continuous and time-varying loadings. These were determined in terms of load spectra on the basis of secured traceable mass and process data for each production area (Fig. 6a). These load spectra are characterised by high individual wheel loads of up to 400 kN to 740 kN (and up to 16 wheels per girder). Fig. 6b shows an example of heavy loaded cranes with 12 wheels for each side typically driving on the investigated crane runway girders. Due to the high number of load cycles for each crane crossing and in particular due to the heavy wheel loads, the girders experience a high local fatigue loading in the flange to web connection areas. However, it is quite astonishing that the majority of the beams (95 %) do not show any fatigue cracking at the corresponding weld.

(a)

(b)

Fig. 6. (a) Typical transport analysis for load spectrum determination; (b) typical heavy loaded crane with 12 wheels