Hillhouse Pedestrian Bridges

2005–2010 | New Haven CT

Client Yale University and The City of New Haven
Lead Designer and Structural Engineer Guy Nordenson and Associates
Architect Pelli Clarke Pelli Architects
Awards 2012 SEAoNY Excellence in Structural Engineering Award, 2011 International Footbridge Award Finalist, 2010 NCSEA Excellence in Structural Engineering Outstanding Project Finalist

When the Hillhouse Avenue vehicular bridge in New Haven CT was reconstructed the pedestrian passageways were separated as two independent foot bridges to align with the existing axes of the sidewalks along the avenue. The set of bridges span 60ft clear over a historic former canal and railway on the campus of Yale University and are made from a high-performance, high-strength steel (HPS70W) and supported on concrete abutments with granite coping. The bridges are identical apart from their widths—the east bridge has a clear width of 10ft while the west bridge has a clear width of 8ft. Each pedestrian bridge consists of two 46in deep steel plate girders which comprise the primary structure as well as the handrails. The plate girders have 1/4in-thick corrugated, perforated webs and are the first of their kind.

The perforations in the web are diamond-shaped and uniform in size. They reduce the weight of the structure and create a lattice-like appearance that recalls the original wood lattice canal bridges designed by local architect Ithiel Town in this part of Connecticut. While the footbridges resemble historic Town truss bridges, the structural forces move through the web in a different manner as a result of the corrugation. The bridges are an inventive re-interpretation of a traditional design.