New Connection Detail to Connect Precast Column to Cap Beam using Ultra-High-Performance Concrete in Accelerated Bridge Construction Applications

Accelerated bridge construction (ABC) is a paradigm change in delivery of bridges. ABC minimizes the traffic interruption, enhances safety to public and workers by significantly reducing on-site construction activities, and results in longer-lasting bridges. The use of precast elements is gaining attention owing to inherent benefits of accelerated construction. Designing an economical connection is one of the main concerns for these structures. New improved materials such as ultra-high-performance concrete (UHPC) with superior characteristics can provide solutions for joining precast concrete elements. In this paper two types of column to cap beam connection using UHPC are proposed for seismic and non-seismic regions. Among the merits of the proposed details, large tolerances in construction and simplicity of the connection can be highlighted which facilitates and accelerates the on-site construction time. The experimental program was carried out to evaluate the performance and structural behavior of the proposed connections. Four specimens were subjected to constant axial compressive loads and cyclic lateral loading. Results of the experiment showed that the displacement ductility of the specimens, incorporating suggested details, demonstrated adequate levels of displacement ductility. More importantly, the proposed connections prevented the damage into capacity protected element—in this case the cap beam. Analytical and nonlinear finite element analysis on the specimens was carried out to better comprehend the behavior of the proposed connections.