Durability of Piles for Water-Level Pile Caps for the Gov. Mario M. Cuomo Bridge

The new Governor Mario M. Cuomo Bridge spans the Hudson River between Rockland and Westchester Counties in southern New York. The Hudson is estuarine in nature at this location, and thus the water is brackish and subject to tidal fluctuations and additionally contained Sulfate Resistant bacteria. The new bridges are constructed using water-level pile caps, with exposed piles from the underside of the pile cap to the river bed. Concrete pile plugs were included to transfer loads from the pile caps into the piles. This presentation will discuss the approach to achieving the desired service life for the piles used for the majority of the foundations, including how the interaction between the steel piles and the concrete pile plugs was accomplished. The assessment considered embedded zones, submerged zones and splash zones, all defined based on actual environmental exposure and with guidance from the FHWA, Caltrans, Eurocode and other publications in conjunction with site-specific testing of the water.