Influence of Hot Dip Galvanizing on the Fatigue Behaviour of T-studs for a Grouted Joint of Integral Composite Frame Bridges

Recent investigations paved the way for hot dip galvanizing in the field of bridge constructions [1]. Due to technical limitations of hot dip galvanizing, steel girders longer than 16 meters have to be divided and connected afterwards. The Chair of Metal Structures works in cooperation with the Chair of Concrete Structures of the Technical University of Munich (TUM) and the Bundesanstalt für Materialforschung und ‐prüfung (BAM), to develop a grouted joint connection, which is suitable for hot dip galvanizing. In contrast to welding the segments on site or using prestressed bolt connections, the hot dip galvanization of the grouted joint remains undamaged for the whole service life time of the structure. As part of this research, the main component of the grouted joint ‐ a hot dip galvanized T‐stud ‐ is investigated regarding its fatigue behaviour. The present paper outlines the idea and the structure of the grouted joint and classifies the hot dip galvanized T‐stud according to a fatigue class given in EN 1993‐1‐9 [2]. Furthermore, the fatigue assessment for the grouted joint and an optimization of the geometry of the T‐Studs is carried out using finite element analysis.