P 1255 – Required Weld Quality for an Adherence of the Safety Requirements for Fatigue Loaded Steel Constructions
The project “Required Weld Quality for an Adherence of the Safety Requirements for Fatigue Loaded Steel Constructions ” deals with the evaluation of optimised weld seam designs. The aim of the research project is to comply with and verify the existing safety standard of welded, fatigue loaded steel structures with simplified manufacturing processes and types of execution and to develop and verify design approaches for the associated types of execution and execution qualities.
In this research project the arising imperfections using simplified welding design types and procedures which have been proposed by the industry are analyzed and their influence on the fatigue strength of steel constructions is determined. The weld imperfections root failure, incomplete root penetration, undercut and axial misalignment are in the spotlight. The allowable fatigue strength as a function from the arising imperfections is be defined based on the experiments. Furthermore, the weld quality and the corresponding fatigue strength has been determined for specific design types. Based on the experimental derived fatigue strength for different weld imperfections the application limits of existing design rules are reviewed and if necessary the calculation methods are adapted. In addition to the efficient nominal and structural stress concepts, findings from the local notch stress concept will be included.
The result is a proposal for a verification method based on nominal and notch stress concepts. This proposal will be presented to the relevant committees for discussion. The present project results enable steel construction companies to design in a resource-saving way with lower production costs than before by meeting the required safety standards. Personnel-intensive work can be reduced, as the reworking currently required due to the high demands on the execution quality of the weld seams can be omitted. Steel construction companies (primarily kmUs) and related industries achieve significant competitive advantages nationally and internationally.
Prof. Dr.-Ing. I. Engelhardt, Prof. Dr.-Ing. K. Rother