Experimental testing of innovative panel-to-panel connections for precast concrete building cores

•Strength/stiffness of stitch plate connections depends on the stud configuration.•The innovative grouted panel pocket is a tested alternative for stitch plates.•Grouted panel pocket was 1.7 times stiffer and stronger than the stitch plate.•The innovative post tensioned corbel is a tested alternative for wet joints.•Post tensioned corbel was greater than 40 times stiffer than the stitch plate. This paper presents the experimental testing and results of a recent study into panel-to-panel connections for jointed precast concrete building cores. Panel-to-panel connections are typically used to transfer vertical shear forces between adjacent panels to allow the individual panels to act as one combined composite cross-section. The experimental program consisted of three specimens, each constructed using a different type of connection. The first specimen was the ‘baseline’ specimen and was constructed using ‘industry standard’ welded stitch plate (WSP) connections. The second and third specimen were constructing using two new prototype connections, which were developed by the authors and are referred to as grouted panel pocket (GPP) and post tensioned corbel (PTC) connections. These connections were developed such that precast concrete building cores could be constructed without the use of wet joints or site welding, which are both costly aspects in precast wall construction. The experimental assessment showed both connections were stronger and stiffer than the baseline WSP connection. The paper is concluded with a detailed overview of the critical failure mechanism of each connection and the development of respective design models that could be used to predict the design performance of the connections.