Silman developed a unique geometric solution for the design of this new, 200-foot pedestrian bridge – a striking centerpiece for the new Yards Waterfront Park on the Anacostia River. At the center of the ongoing redevelopment of DC’s Southeast Waterfront and the restoration of the Navy Yard, the new bridge spans the site of Washington’s first canal. The bridge has a dramatic curved, sweeping geometry that creates a feeling of compression at its center, and then release as one walks from one side to the other. With every carefully contoured element of the bridge participating in the behavior of the span exposed, and in arm’s reach, the public is invited to approach and enter this unique form to interpret its physical function.
Silman’s greatest design challenge was balancing the flow of forces through the structure while satisfying the aesthetic-driven form. While the primary structural elements are the pair of canted tied arches, the ribs use vierendeel behavior to provide lateral stability, forming a hybrid structure much like a covered timber bridge. As the ribs were stiffened to resist forces transverse to the arches, and to ensure the top chord’s stability, the ribs attracted more moment in the plane of the arch. Rib stiffeners were designed to provide a sculptural solution to connections, while also providing strength and stability. During design, the bridge fabricator used BIM to assist in reviewing constructability of the schemes, and to develop details such as the built-up rib stiffeners.
The completed bridge was celebrated with a grand opening ceremony and ribbon cutting on September 7, 2010.
2010 ACEC-MW, Engineering Excellence Honor Award
2011 ACEC, Engineering Excellence National Honor Award
2011 SEA-MW Excellence in Structural Engineering Outstanding Project Award
2012 National Steel Bridge Alliance Prize Bridge Competition Merit Award
Categories: Special Structures