An experimental investigation on the dovetail notched connection for cross-laminated-timber-concrete composite slabs

This paper presents an experimental study on the behaviour of notched connectors with a dovetail shape. A series of three symmetrical push-out tests on connection specimens and a series of two full-scale flexural tests on slab specimens were carried out. The test results of the push-out tests showed high shear resistance and stiffness of the connectors. However, the ductility of the connectors was low, as the failure mode was governed by the shear failure of the cross layer of the CLT. In addition, it was shown in the flexural test results that the design of the composite slab is not limited by the flexural bearing capacity as a high value of the maximum bending moment was obtained in the tests. It is instead governed by the deflection of the composite slab. Besides, a modified gamma method was used to estimate the mid-span deflections and compared with the ones obtained from the flexural tests. A good agreement was obtained, validating the use of the method to estimate the stiffness of the CLT-concrete slab with Dovetail notched connection. In addition, a beam grid model was also employed in order to take into account the stiffness of the slab in the transversal direction.