Major River Crossings - Challenging Design & Construction [B12] 2024

The design and construction of major bridges across large navigable rivers presents many unique challenges. Not only from the bridge type and span arrangement selection, but also from the impacts of navigation traffic on the viable construction techniques and the impact of those challenges to refining the design of the bridge superstructure. This session will highlight two recently constructed steel bridge projects and how these challenges were overcame. The US 60 Smithland Bridge over the Cumberland River crosses a difficult s-curve stretch of the navigable river. The final design featured a 700-ft span modern Warren truss design featuring simplified connections, eliminated sway lateral bracing, and a mix of open and closed truss shapes for fabrication efficiency. During construction, the Contractor had to develop a float-in concept for the 700-ft truss span that utilized a riverport facility for erection and a 15-mile fload up the Ohio River and into Cumberland River before being lifted into place, one of the longest known float-ins in North America. A $224 million WVDOH design-build project along Interstate I-64 near Charleston, WV features dual-structure steel I-girder river crossings with main spans of 562’-6”, the longest in the United States. The structure configuration and span lengths took advantage of existing substructure units, a navigable river, strand-jacking to lift the main span, and a “conventional” superstructure type to provide a cost-effective winning solution. While the superstructure was a “simple” steel girder bridge, its size and site constraints presented many design and construction challenges including shipping lengths and piece weights; details to allow flexibility for fabricators; and complex analysis considerations such as nonlinear buckling, live load time history, thermal gradient, and others not often associated with steel girder bridge.

Speaker(s): Taylor Perkins, SE, PD, PhD, Tony Ream, PE, Jason Fuller, PE, Austin Hart