The Governor Mario M. Cuomo Bridge, NY, USA: solutions to complex geotechnical conditions Available to Purchase

Deriving its name from a local Native American tribe and the Dutch word for sea, the Tappan Zee (NY, USA) is perhaps the most difficult section along the Hudson River for building a bridge. Swells of 1 m, swift tides, winter storms and ice flows aside, the 5 km crossing faces daunting circumstances beneath the surface in the form of poor and varied geotechnical conditions. Innovative design and construction first found a solution to these challenges in the 1950s with the completion of the Tappan Zee Bridge. However, with traffic volumes exceeding its design basis, exponentially increasing maintenance costs and functionally obsolete features, ‘the Tapp’ was nearing the end of its serviceable life. Its twin-span replacement, the Governor Mario M. Cuomo Bridge, took a diametrically different approach to the river and its complex soil strata. This paper looks back briefly at the unique floating bridge strategy used in the 1950s before examining the deep-foundation approach of the 2010s. The US$4 billion Cuomo Bridge took advantage of new resources such as driven pipe piles more than 115 m in length, large-displacement isolation bearings and modular joints and the use of prefabricated components and several massive barge-mounted cranes.