Design and behaviour of moment resisting precast concrete connections with cast-in shear fasteners

Abstract

The paper proposes a novel design procedure for an innovative connector that provides flexural continuity between ribbed precast concrete flooring units. The innovation was driven by the goal of rapid onsite assembly which precluded the use of structural toppings, complex in-situ stitching of projecting bars or onsite welding. Assembly on site is a simple process of bringing the precast elements together on temporary supports and grouting the prefabricated steel connectors into well-voids cast into the member ends. The benefits of the developed connection have been successfully demonstrated within a number of full-scale prototypes. Due to the novel and unconventional form of the proposed connector, physical testing was crucial to provide an in-depth understanding of its response characteristics under serviceability and ultimate loading conditions. Towards this end, three full size specimens were tested to failure under four-point bending. The outcomes of these experiments are used to validate 3-D high-fidelity nonlinear finite element analysis models. These are finally used in a wide-ranging study to demonstrate the applicability of the proposed design procedure for this novel precast concrete connection system.