NCHRP Research Report 895 presents new simplified connections between full-depth precast concrete deck panel and beam with proposed AASHTO LRFD Specification language for the design, fabrication, and construction. The new connection systems are based on comprehensive analytical and testing programs, and the proposed specification language presented with design examples. The new system utilizes clustered shear connectors spaced up to 6 ft and connected to the deck system using Ultra-High Performance Concrete (UHPC). In addition, the new system utilizes discrete joint connections (i.e. non continuous haunch) to eliminate blind grouting. The material in this report will be of immediate interest to bridge engineers.
Full-depth precast concrete deck panels have been widely used in accelerated bridge construction (ABC) in various forms and sizes. As a prefabricated component, full-depth deck panel systems meet the objectives of ABC by expediting construction, improving quality and durability, improving public and worker safety, and reducing road user impact. Typically, deck panels are connected to the supporting beams by shear connectors in formed openings in panels (i.e., shear pockets) to achieve composite action between deck panels and beams of a bridge. The current use of shear connectors at small spacing poses several constructability challenges due to the large number of connectors and pockets. One of the challenges is the work associated with blind grouting/concreting the numerous shear pockets and the longitudinal haunch between the deck panels and the beams. Specifically, the leveling, sealing, forming, grouting, and concreting can be time consuming and require access from above and below the deck. This access requirement may create adverse traffic impacts. A new deck connection that can overcome these constructability challenges by reducing the number of shear pockets and eliminating blind grouting would provide additional benefits to this construction technique.
Under NCHRP Project 12-96, the George Washington University was asked todevelop recommended guidelines and proposed AASHTO LRFD Specification language for the design, fabrication, and construction of a new full-depth precast concrete deck panel system that simplifies the connection between the deck panel and beams.
A number of deliverables, provided as appendices, are available at
- Appendix A – Literature Review
- Appendix B – Analytical Program
- Appendix C – Shop Drawings