Tuesday, September 14
2:30 - 3:00 PM
The new Rich Street Bridge is a landmark structure spanning the Scioto River in downtown Columbus, Ohio. The new bridge is a 5-span, 563-foot-long modern concrete arch structure, designed to be pedestrian-friendly and to accommodate community festival events. The bridge is one of three crossing the Scioto River in the city’s historic Civic Center. The configuration of the new bridge was selected in response to design criteria set by community representatives requiring that the bridge compliment the surrounding “family” of arch bridges while respecting the architectural character of the surrounding area. The design and construction methods were influenced by a sudden mid-project acceleration in schedule aimed to ensure the bridge would be open in time for the City’s Bicentennial celebrations. Design refinements were made to shorten construction by seven months and reduce the estimated project costs by $10 million.
The bridge is supported on four lines of concrete arch ribs which are constructed integrally with the bridge’s four girder lines so that the resulting structure behaves as a rigid frame. Both the arches and girders consist of precast concrete segments constructed using high strength lightweight concrete. Standard radii and cross-sectional dimensions were established for the precast segments to allow common formwork to be used for each segment type. The precast segments were erected on temporary shoring and tied together with cast-in-place closure splices. The arches, girders, and the deck are longitudinally post-tensioned over the entire length of the structure, resulting in a fully integral superstructure that is more durable without the presence of intermediate expansion joints.
This presentation will cover the genesis of the bridge type; the precast segment design, layout, and details; analysis methods; the erection/construction sequence; and various special considerations. The use of lightweight precast concrete, field spliced post-tensioning, and a minimal number of efficiently tailored segments advances the boundaries of what can be achieved with precast concrete – melding aesthetic, durable and economical bridge design.