Date of this Version
El-Khier, M. A. and Morcous, G. (2019). Precast Concrete Deck-to-Girder Connection Using UHPC. NDOT Research Report SPR-1(19) M085.
The implementation of ultra-high-performance concrete (UHPC) in bridge construction has been growing rapidly in the last two decades due to its excellent mechanical properties, workability, and durability. This report presents a new UHPC connection between precast concrete deck panels and bridge girders that eliminates changes to the design and production of girder shear connectors commonly used in conventional cast-in-place concrete deck construction. In conventional construction, girder shear reinforcement or studs are extended into the cast-in-place concrete deck to transfer interface shear and create composite section. In the new connection, girder shear reinforcement or studs are kept underneath the deck panels, while UHPC is used instead to fill the haunch and shear pockets and transfer interface shear between deck panels and girders. Using UHPC and eliminating changes to standard shear connectors make precast concrete deck systems more economical and enhance their constructability.
The report presents the experimental investigation conducted to evaluate the interface shear resistance of UHPC using direct shear, slant shear, L-shape push-off, and double shear tests. Also, three full-scale specimens of the new connection were constructed and tested to evaluate its structural performance and constructability. Based on the experimental investigation results, empirical equations were developed to predict the interface shear resistance of the new connection and develop design aids for different bridge types and configurations. Design procedures and construction recommendations were also developed based on the outcomes of the experimental investigation.