There is a growing need for durable and resilient prefabricated bridge systems which facilitate rapid completion of on-site activities in order to minimize the impact on the travelling public. Prefabricated bridges can provide higher quality, accelerated, and safer construction. However, greater offsite prefabrications of bridge components necessitates an increased reliance on the long-term performance of field-installed connections between these components. Of particular interest here, ultra-high performance concrete (UHPC) can exhibit exceptional bond when cast against previously cast concrete and can significantly shorten the development length of embedded discrete glass fiber reinforced polymer (GFRP) bars. With the recent innovations in bridge infrastructure replacement, the use of UHPC in closure strips between precast concrete bridge segments became the main focus of bridge owners for its superior strength and durability. To increase competitiveness in supplying UHPC to bridge owners in Canada, this collaborative research with the industry is looking into an innovative UHPC design that combines both high concrete compressive strength, and enhanced durability and rheology. It is essential to produce design standards and performance-based specifications of UHPC through experimental trial and errors due to lack of reliable information in this subject in the related standards and literature. This research investigates different UHPC mixes designed to reach the desired strength and rheology. While UHPC materials clearly outperform conventional concrete in mechanical and durability performance, their production is proprietary and the development of economically competitive alternatives is warranted. Throughout this research, the desired fresh and hardened concrete properties as well as practical mixing procedure were achieved and reported herein.
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