Structures such as bridges, towers, masts or cranes are not predominantly static loaded, why the fatigue strength of the components can be decisive for dimensioning. Thereby the detail catalogue according to EN 1993-1-9, which bases on a collection of test data and was processed in a previous project, plays a central role. It was found that the classification of some details is very general, although a more economical differentiation would be possible. On the other hand, the test data do not always confirm the sometimes very detailed classifications. Another deficit is the lack of a link between detail category, weld and manufacturing quality. Although many construction details show a link between fatigue strength and execution quality. In addition, evaluation methods for tolerance deviations of welded constructions should be added for an economic fatigue design.

The project aim is to optimize the detail categories of frequently used construction details. Therefore, the detail catalogue should to be designed in a much more advantageous and realistic manner based on a further developed test database and to be adapted to the new possibilities of manufacturing and non-destructive testing. The more realistic classification of details offers the possibility of a better link between execution qualities (EN 1090, EN ISO 5817) and design requirements (EN 1993 1 9). The resulting adaptation of the detailed categories is intended to help improve profitability of steel structures and increase the competitive chances.