Corrosion at steel beam ends is one of the most pressing challenges in the maintenance of aging bridges. To tackle this challenge, the Connecticut Department of Transportation (DOT) has partnered with the University of Connecticut to develop a repair method that benefits from the superior mechanical and durability characteristics of ultra-high performance concrete (UHPC) material. The repair involves welding shear studs to the intact portions of the web and encasing the beam end with UHPC. This provides an alternate load path for bearing forces that bypasses the corroded regions of the beam. The structural viability of the repair has been extensively proven through small- and full-scale experiments and comprehensive finite element simulations. Connecticut DOT implemented the repair for the first time in the field on a heavily trafficked four-span bridge in 2019. The UHPC beam end repair was chosen because of the access constraints and geometric complexities of the bridge that limited the viable repair options. Four of the repaired beam ends were fully instrumented to collect data on the performance of the repaired locations before casting, during curing, and for approximately 6 months following the application of the repair. This paper provides an overview of the successful repair implementation and presents the lessons learned during construction. Select data from the monitored beam ends are presented. It is expected that this information will provide engineers with a better understanding of the repair implementation process, and thus provide an additional repair option for states to enhance the safety of aging steel bridges.
Performance evaluation and finite element verification of an ultra-high performance concrete pi-girder bridge