On the load-bearing behaviour of closed bonded dowels under static and non-static loadsload in steel composite construction

In reinforced concrete composite construction, composite elements are used to ensure force transmission between steel and concrete components. For more than 50 years now, the most commonly used composite means for the transmission of shear forces in conventional steel composite construction has been the headed bolt dowel, which is currently standardised in DIN EN 1994. In addition to shear stud dowels, composite dowel bars can be used as an alternative. Their use has been regulated in the past in general building inspectorate admissions and currently in the general type approval Z-26.4-55 of the German Institute for Building Technology (DIBt).

Composite dowel bars have a number of mechanical and practical advantages over shear stud dowels. Composite anchor technology is to be regulated in the new generation of standards DIN EN 1994 for Europe-wide use in the future. The normative introduction will pave the way for the increased use of open bonded dowel bars for the transmission of longitudinal shear forces in the bonded joint of steel composite cross-sections; however, the question arises:

Why should composite dowel technology not be used in other areas of the structure, e.g. in junctions for the local transfer of shear forces?

An analysis of international scientific progress shows that this form of construction is mainly being investigated in Asia (China, Japan, Korea) and Eastern Europe. The publications to date are still incomplete in some areas. In order to establish this technology in the German and European construction industry, both static and fatigue analyses must be advanced and put up for scientific discussion.

In the medium term, the Department of Steel and Steel Composite Construction at the University of Applied Sciences Potsdam would like to develop a design proposal for static and high-cycle loads on closed composite anchors and demonstrate the practical construction potential and limits of this type of composite on the basis of an extensive test programme. As part of the research focus "Closed bonded dowels (CCD)", initial experimental investigations were carried out in the Department of Steel and Steel Composite Construction. The investigations provide information on the influence of different design parameters (drill hole diameter, dowel diameter and chamber width) on the load-bearing behaviour. These findings form the basis for further theoretical investigations and the planning of additional test series in order to deepen our understanding of this type of connection.