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11 S U M M A R Y Application of Accelerated Bridge Construction Connections in Moderate-to-High Seismic Regions Increasingly, state DOTs are supporting initiatives to study and apply Accelerated Bridge Construction (ABC) techniques to bridge projects. They offer the potential benefits of reduced construction time, minimum traffic disruptions, reduced life-cycle costs, and improved con- struction quality and safety. Prefabrication of components is a promising approach to ABC but, in seismic regions, the connections between the elements must not only be easy to con- struct, but also must be robust enough to maintain their integrity under seismic loading. Development of connections and systems that satisfy these criteria will constitute significant progress in achieving the goals of ABC. This report presents results of a literature review of the connections and systems that are currently in use, or are being studied for use, in ABC in the United States and other countries. A survey questionnaire was developed to involve bridge owners such as the FHWA, state DOTs, domestic and international universities and organizations, contractors, precast pro- ducers, and vendors. The ABC connections identified in the literature study and survey are analyzed and catego- rized by type, such as bar couplers, grouted ducts, pocket, socket, hybrid, or integral connec- tions, and emerging technologies, such as shape memory alloys and elastomeric bearings. Note that seismic isolation may also be used with ABC techniques; however, seismic isolation is a relatively mature technology and is not evaluated herein. A primary objective of the project was to evaluate and rank the connections. This was done using three parallel metrics: technol- ogy readiness, performance, and time savings potential. The technology readiness level is a measure of the development of the connection or system technology, and depends on the extent to which it has been tested, analyzed, and deployed. The performance evaluation includes characteristics, such as expected seismic performance, constructability, durability, inspectability, and reparability. Time savings potential is measured relative to cast-in-place construction. Gaps in the development of each connection type were identified. These rank- ings identified the ABC connections and systems that most urgently warrant further research, such as grouted splice bar couplers and development of a bent system, as well as subsequent development of integral connections and emerging technologies. An extensive testing program will eventually be necessary to support the use of the various types of ABC connections that could be deployed in medium-to-high seismic regions of the United States. In addition, definitive design and construction specifications, design examples, demonstration projects, and field experience will be needed for owners, contractors, and designers to have the confidence to deploy the technology.
