Constructability of Full-Depth Precast Deck on a Steel Girder Bridge with Injection Channel Connection

In this study, the constructability of a full-depth precast deck installation on a steel girder bridge with injection channel connection was evaluated. This type of girder has been developed to avoid the overlap between the shear studs and the bridge deck, which is a major issue causing delays in modular construction. First, the optimal dimensions and lifting method for the deck were determined through finite element analysis. Subsequently, the constructability of deck installation on the bridge was evaluated with various radii of curvature using building information modeling (BIM). For the efficient use of BIM, algorithm-based models for the girder and deck were developed to change their shapes easily.

Learnings from the Field Implementation of a Novel Ultra-High Performance Concrete Beam End Repair on a Corroded Steel Girder Bridge in Connecticut

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.

Characterization of operational vibrations of highway bridges Via Lidar

<p>During the examination of data obtained from scanning an operational steel girder bridge, local ripples were noted in horizontal elements that were expected to be planar in nature (such as girder flanges). It was hypothesized that these ripples are a result of the bridge vibrating under truck traffic. The objective of this paper is to examine this hypothesis through the use of data obtained from an operating highway bridge together with the use of numerical and physical models. After analyzing the data, by estimating the distance between the peak of these ripples (and translating this into time using the data acquisition metrics) the frequency of the vibrating object can be estimated. For the operating bridge and physical model employed in this research, the natural frequencies were estimated within 2% to 10% and 0,22% to 5%, respectively.</p>