A value engineering study for the Arbor Rail Line Bridge replacement in Nebraska City, Nebraska, resulted in an innovative precast concrete design solution that was accepted over a proposed steel superstructure, saving $70,000 in the project costs. The precast superstructure comprises five box girder sections that create the same profile as the original steel solution. By using a detailed analysis to design the diaphragms and transverse post-tensioning, the five boxes worked together as a single unit to resist the design loads. Additionally, since the entire superstructure consisted of only five precast components, the box-girder system allowed the new bridge to be erected and opened to traffic within 72 hours. This article provides the design considerations and construction highlights of the project.
