Shear-Transfer Mechanism and Design of Shear Connectors for Full-Depth Precast Deck Panel System

摘要

The development and implementation of full-depth, precast overhang panel systems has the potential to improve constructibility, productivity, and make bridges more economical. Recently, various shear connector systems have been proposed to provide shear-transfer resistance between girders and the precast overhang panels. There is, however, limited information and guidance on the design for shear-transfer capacities for full-depth, precast overhang panel systems. This research performed experiments and assessed the results to estimate the shear-transfer capacities of four types of shear connectors systems. The confinement system of the shear pocket was varied with the hopes of enhancing the shear-transfer capacity. Results indicate that five stages of shear-transfer and failure mechanisms occur during testing. These stages include initial adhesion loss, shear key action, shear key action failure, dowel action of the shear connectors at a sustained load, and final failure of the system. Results from this research indicate that steel reinforcing hoops placed in the shear pocket and shear reinforcing hoops placed in the overhang panel around the opening of the shear pocket provide limited or no improvement in capacity of the shear connector/coupler system. When comparing energy absorption capacities, however, the shear connector systems evaluated can provide improved performance when compared with the conventional R-bar system. A new equation is proposed based on this research.