Headed shear stud connectors in a stub-girder floor system: a preliminary study

Abstract

The performance of headed shear stud connectors which attach the reinforced concrete slab to the supporting structural steel stubs in a stub-girder structural floor system was examined by testing 28 portions or subassemblages of a complete stub-girder. The major difference which affected the performance of the shear connectors in a stub-girder floor system as compared with conventional composite construction was the increasèd tension which must be carried by critically located shear connectors. One cause of the increase in tension was the secondary bending which resulted from the transverse (beam) shear acting on the concrete slab along the open panel of the stub-girder between interior structural steel stubs. This behavior is similar to the bending which takes place in the chords of a Vierendeel truss.A significant reduction in the shear strength of the connectors resulted from the induced tension. However, the shear strength could be predicted using current Canadian code strengths if allowance was made for the tension in the connectors. The analysis suggested that the resultant of the full applied shear force and 75% of the applied tension force was comparable with the shear connector strength given in the code.