A significant portion of the existing roadway system in the United States was built over 50 years ago and is widely showing signs of increasing deterioration. Construction activities related to bridge replacement and rehabilitation are important contributors to traffic jams and reduced mobility and, most importantly, to safety hazards. Conventional construction practices have proven inadequate to address the magnitude of the problem now facing this nation. Highway system disruptions due to work zones must be considered when evaluating the need for rapid renewal procedures. Accelerated Bridge Construction (ABC) has the potential to reduce both the frequency and duration of work zone disruptions. ABC is a delivery solution method for building and repairing bridges with the capability to reduce the interruption to traffic and increase safety. UHPC provides a new horizon for addressing many actions that are needed to be taken to address the challenges facing the nation with respect to existing bridges. At ABC-UTC, researchers have developed many UHPC based solutions that can retrofit/upgrade existing bridges or be utilized for the construction of new bridges. These solutions include systems where formwork is replaced by a UHPC shell that becomes a permanent part of bridges, connections for connecting prefabricated bridge elements, 3D printing, automation, durability, and fire resistance of bridge elements constructed using UHPC, advanced integral abutment systems, shotcrete and more. This presentation will provide an overview of some of the UHPC based solutions, developed at ABC-UTC.

The functionality and crashworthiness of concrete barriers in bridge systems can be affected by the deterioration of the connection between bridge decks and concrete barriers. A set of details for barrier-to-deck connections for accelerated bridge construction (ABC) applications are proposed. Component-level testing was carried out on a conventional cast-in-place (CIP) detail and two versions of connections using ultra-high-performance concrete (UHPC). The use of UHPC allows for shorter development length and lap splice length for dowel bars and the material characteristics provide strength and durability to the connection. Two connection details were proposed: (1) UHPC connection within the barrier segment (U-shape connection) and (2) UHPC connection in a recess inside the bridge deck (recessed connection). Besides simplified details, the construction sequence of the proposed recessed connection is suitable for ABC applications. It is observed that the proposed U-shape connection detail is emulative of the equivalent CIP concrete barrier system. However, the recessed connection system can undergo significantly larger deflections at ultimate load compared with the CIP barrier system and exhibits a preferred mode of failure while the deck does not undergo significant damage. The results of the component testing were used to calibrate non-linear finite element models. Using validated models, numerical analyses were performed to investigate the structural performance of conventional 15 ft long barrier modules connected to the deck overhang using the recessed connection. The model was subjected to the end-loading configuration and it was found that the proposed barrier system meets the strength requirement for the corresponding test level.