Behavior of post-installed shear connectors under static and fatigue loading

This paper describes a series of tests investigating methods to develop composite action in existing non-composite floor systems. Three types of 22-mm diameter post-installed shear connectors were tested under static and fatigue loading. Test results are compared with previous research results on 19-mm diameter, post-installed shear connectors as well as with conventional welded shear studs. Based on the test results, preliminary design equations are proposed for the static and fatigue strength of post-installed shear connectors. These post-installed shear connectors showed a significantly higher fatigue strength than conventional welded shear studs. The superior fatigue strength of these post-installed shear connectors enables the strengthening of existing bridge girders using significantly fewer shear connectors than possible with conventional welded shear studs.