PSI - Issue 64

Cedric Eisermann et al. / Procedia Structural Integrity 64 (2024) 1224–1231 Eisermann et al./ Structural Integrity Procedia 00 (2019) 000–000

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4. Discussion and Outlook According to the German Recalculation Guideline, the partial factor for the dead load may be reduced from 1.35 to 1.20 if the actual load distribution is precisely known. Alternatively, fib Bulletin 80 provides two methods to adjust the partial factor to the object-specific self-weight distribution on a probabilistic basis. In this case, the planned load distribution can be used to determine the internal forces. The application of the DVM and APFM to the Nibelungen Bridge has shown that a reduction of partial factors above 1.20 is possible in case the uncertainties related to geometry and density of the concrete are known. Both methods yielded similar results. However, further investigations into the geometry of the whole river bridge, the weight of the concrete, and the reinforcement content are required to justify a reduction in the dead load partial factor of the Nibelungen Bridge. In general, investigations of this nature are associated with high financial costs. Therefore, further research will be conducted to determine how the results from the pilot area can be generalized and applied to a measurement concept for the entire bridge and other bridges Furthermore quality requirements for as-is models will be investigated in order to standardize the model comparison and, subsequently, the reduction of the dead load partial factor. Acknowledgements This research was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) as part of the priority program (SPP 2388) “Hundred plus - extending the service life of complex structures through intelligent digitalization” (project numbers: 501808860 and 501804558). References Boros, Vazul (2019): Reassessment of the partial safety factor for self weight of existing bridges. In International Probabilistic Workshop 2019. Edinburgh, United Kingdom, September 11 to 13, pp. 75–80. 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