Zum Beultragverhalten längsausgesteifter Biegeträger nach Eurocode - Vereinfachungen und zutreffende Vorgehensweise

Plate buckling capacity of longitudinally stiffened girders using the Eurocode - Simplified and improved rules.

Plated girders with longitudinally stiffened webs, used for example as main girders for steel and composite bridges, are now designed based on the Eurocode EN 1993-1-5. Applying the traditional used reduced stress method, for practical examples often conservative results - compared to the old national codes (ÖNORM, DIN) - are found.
Based on this fact, nonlinear calculations were done to compare the ultimate plate buckling load with the design in the Eurocode. The results of the study are presented in this paper as well as an improved rule to get better results with the Eurocode. At the beginning the design rules of the Eurocode are briefly summarised and the differences compared to the existing national codes are presented. After that the studied stiffened web panels and their plate buckling capacity - based on the nonlinear calculations as well as on the rules of the Eurocode - are summed up. Finally the improved rules are presented and some recommendations for practical design are given.