Investigations of the shear connectors and the load‐bearing behaviour of steel cross‐laminated timber composite beams

A strengthening of cross laminated timber (CLT) by a composite effect with steel girders can act as a sustainable option to replace concrete or composite slabs for spans of more than 7 m. The efficiency of a composite structure is strongly influenced by the stiffness of the shear connectors. Therefore, fully threaded screws and shear studs were investigated in double push‐out tests. The screws are inclined to increase their stiffness and are rotated within the drilled hole towards the web, so that a multidimensional load situation with both axial and shear loads results. The shear studs are placed in openings of the CLT and cast in with mortar. The shear tests confirmed that their load bearing behaviour can basically be described with existing analytical calculation approaches. The findings were extended in large‐scale 4‐point bending tests to investigate the bending behaviour of the composite beam.