Take A Dip In your article, Ideas Abound On Crossings Fate, about a suitable replacement for the 50-year-old, 3-mile-long Tappan Zee bridge across the Hudson River, several alternatives are being considered by the New York State Thruway Authority (ENR 4/21 p. 17). One of the obstacles to the selection of a double-deck, steel bridge design mentioned was the painting cost to maintain the bridge. Current painting contracts have cost $23 million for a third of the bridge alone, according to Christopher Waite of the thruway authority.
With hot-dip galvanizing capacities increasing each yearthere are now kettles with 120-ft capacities that could galvanize large girders and beamswhy not consider galvanizing the steel? In many cases, the initial cost of applying the zinc coating of the hot-dip galvanizing process is less than painting and most certainly the life-cycle cost is less because there is usually no maintenance required on hot-dip galvanized steel for 50 or more years. That is a huge taxpayers savings, not to mention the savings in soft costsno traffic jams for repairs!