Experimental Assessment of Fatigue and Ultimate Strength of Stud Clusters in UHPC-filled Shear Buckets for Full-depth, Precast, Concrete Bridge Deck Panel- Steel Girder System

Accelerated Bridge Construction (ABC) is becoming an innovative construction solution to minimize construction cost and delivery time while increasing durability and improving safety. The common approach in ABC involves installing full-depth precast concrete deck panels on top of steel girders such that the shear pockets in the panels are aligned with a cluster of studs welded to the top flanges of the girders. This thesis presents a study on fatigue and static behavior of headed shear studs in composite girders where ultra-high-performance concrete (UHPC) was used as the connection grout in the shear pockets. The experimental program consisted of both static and fatigue testing on composite sections. The first phase of this research involved static and fatigue push-out tests on six specimens in which studs were grouped in different arrangements and spacings. The second phase of this research involved fatigue tests, followed by static tests to collapse on 5 composite beams. Three shear pocket spacings were considered in this study, namely: 600 mm, 1200 mm, and 1500 mm, along with a control cast-in-place specimen that was constructed using evenly distributed studs. Results were analyzed in comparison with the CSAS6:19 code provisions. Then, conclusions for the fatigue and ultimate strength of the clustered studs in UHPC-filled shear pockets were drawn.