FEATURE ARTICLE Custom fabricated picking and suspension ring The Kosciuszko Bridge, named in honor of Polish military engineer and Revolutionary War hero Tadeusz Kosciuszko, carries I- 278 over Newtown Creek, the dividing line between the New York City boroughs of Brooklyn and Queens. At the time of the bridge’s construction in 1939, Newtown Creek was an industrial hotbed lined with petroleum refineries, coal handling facilities, metal processors, and chemical and fertilizer manufacturers. The waterway became one of the largest shipping hubs in the Northeast, and to accommodate the maritime traffic, the existing Kosciuszko Bridge was constructed with a fixed span 125 ft (38.1 m) above the mean high water level. This resulted in a structure that now features nonstandard roadway grades on both approach spans, inadequate sight distances across the main span and entrance ramps with insufficient merge lengths. Serving more than 160,000 vehicles per day, the bridge has become AUTHOR New Kosciuszko Bridge – Transforming the New York City Skyline The new Kosciuszko Bridge is designed notorious locally for its state of structural disrepair and severe congestion. In May 2013, the New York State Department of Transportation (NYSDOT) awarded a design-build contract to the joint venture of Skanska USA Civil Northeast, Kiewit Infrastructure Company and ECCO III Enterprises (SKE), in conjunction with design partner HNTB New York Engineering and Architecture. The project scope includes design and construction of a new eastbound bridge and improvements along a 1.1 mi (1.8 km) segment of the Brooklyn-Queens Expressway (BQE), as well as demolition of the existing bridge. With the exception of some minor replaceable items, the bridge has a required 100-year design service life. A new westbound (Brooklyn-bound) bridge, built within the footprint of the existing Kosciuszko Bridge, will be completed under a separate contract. as a cable-stayed structure, the first of its kind in New York City. The approach span piers and connector abutments, not discussed in this article, are supported primarily by driven piles, along with a limited number of micropiles at several abutments constructed under low- headroom conditions. At the center pylon, rock- socketed dr i l led shaf t s of unprecedented size and capacity within the metropolitan area were the signature feature of the project’s deep foundation work. Subsurface Profile In the area of the center pylon, on the west bank of Newtown Creek, the general soil profile consists of approximately 20 ft (6m) of urban fill overlying a thin organic clay layer, then glacial deposits composed of silty sand with gravel and a lower clay layer known as the Raritan Formation. Beneath lies a layer of decomposed rock, consisting Nolan S. Kealy, P.E., Foundations Manager, Skanska-Kiewit-ECCO III Joint Venture DEEP FOUNDATIONS • SEPT/OCT 2015 • 87
