Performance of Notched Coach Screw Connection for Timber-Concrete Composite Floor System

The notched connection for timber-concrete composite beams is obtained by cutting a notch from the timber beam andfilling it with concrete during the pouring of the concrete slab. This type of connection has the advantage of high stiffnessand strength compared to mechanical fasteners. The paper presents the outcomes of a parametric study of fourteenvariations of notched connections which were loaded to failure under shear in push-out specimens. Laminated veneerlumber (LVL) was used for the timber part. Stiffness and strength values obtained from the different connectionvariations were compared to each other in order to identify the best types. Rectangular and triangular notches reinforcedwith a coach screw were found to perform satisfactorily. An alternative connection system with punched metal plates wasalso found to perform well, with the additional benefit of ease of construction. The experimental results were comparedwith numerical results carried out using a 3D finite element model implemented in ANSYS software package. Agreementwas found between the predicted and the experimental failure mechanisms, however further work is needed to fullycalibrate the software on the experimental results.