Kosciuszko Bridge – Phase 2
New York City
Owner: New York State Dept. of Transportation
Lead Design Firm: WSP USA Inc.
General Contractor: Granite Construction Northeast Inc.
As part of New York City’s first major bridge crossing since 1964, the $318-million second phase of the Kosciuszko Bridge was completed four years ahead of schedule and on budget, says its team. Combined with the first phase, finished in 2017, an 80-year-old, 1.1-mile structurally deficient segment of the Brooklyn-Queens Expressway has been replaced with two three-lane structures, each with a single-tower cable-stayed main span across Newtown Creek.
Lowering the roadway incline by 35 ft enables trucks and larger vehicles to maintain consistent speed, while a new shared-use recreation lane provides cyclists and pedestrians with safe passage to explore and support neighboring communities. Grounds around the bridge also were converted into public plazas and parks.
The two-phased bridge replacement strategy proved beneficial to expedited completion. After the first phase design-build approach, Phase 2 was implemented as a design-bid-build/best value contract. The second phase design began while the initial phase was underway, allowing completed documents to be ready six months ahead of schedule.
Project team partnering through the design process yielded opportunities to further compress the construction schedule, says the submission. Use of precast elements helped lower costs and save time.
Already unique as a single-tower cable-stay structure with an unbalanced span arrangement, the bridge includes a concrete and steel counterweight at the end of the back span to mitigate the large weight differential. Internal hydraulic dampers installed at each cable absorb energy from high-amplitude vibrations of the cables during wind and rain events, further enhancing the structure’s stability.
Metalized structural steel and a 1-in.-thick polyester polymer concrete overlay atop the precast deck panels will help reduce long-term maintenance needs. Stainless steel rebar in the deck and concrete cap beams under expansions joints will safeguard the structure against future spalling and cracking.