The Rachel Carson (9th Street) Bridge is an eye-bar-chain, self-anchored suspension bridge carrying Ninth Street over the Allegheny River, the Tenth Street Bypass, and Three Rivers Heritage Trail in downtown Pittsburgh. It is one of the “Three Sisters” bridges constructed from 1924 to 1928 that comprise the only trio of identical, side-by-side bridges in the world and the first self-anchored suspension spans constructed in the United States. TranSystems (formerly L.R. Kimball) was assigned the Rachel Carson (9th Street) Bridge and led and coordinated the efforts of the team to deliver the inspection, design and construction services.
The bridge is 995 feet long and consists of two multi-girder steel approach spans of approximately 75 feet and 60 feet in length and a three-span, self-anchored, steel eye-bar suspension bridge that is 860 feet in length. Rehabilitation was required due to accelerating age-related deterioration. Construction work involved replacement of the bridge deck and sidewalks; total repainting of the superstructure; steel repairs of the stringer connections, floor beam connections, stiffening girder, and sidewalk brackets; replacement of numerous sidewalk brackets and all sidewalk fascia beams; updates to structure drainage and lighting; and upper substructure repairs.
