Some Disassembly Required Removing the Old Bridge’s Steel

June 28, 2018
TOP
Some Disassembly Required Removing the Old Bridge’s Steel
NYSTHU_180508_p098lr2

A tugboat helps transport a steel truss section of the old bridge.

As the eastbound span of the Governor Mario M. Cuomo Bridge continues to take its final shape, Tappan Zee Constructors (TZC) is still hard at work dismantling the retired bridge.

Today, TZC raised and removed the 20th and final steel truss section of the old bridge with the project’s largest crane, dubbed I Lift NY.

The massive machine began removing these enormous sections of structural steel, some weighing more than 1,500 tons, in November 2017.

The steel trusses once formed the base for the old bridge’s concrete roadway, connecting the crossing’s piers across the Hudson River. To remove them from the project site, TZC carefully disconnected the structural steel from the old bridge’s concrete piers and cut them into manageable sections, measuring up to 250 feet in length. TZC also removed the concrete roadway panels atop the trusses and placed them on floating barges, where they were prepared for transport and recycling offsite.

Floating barges are also be used to manage the removal of the final steel truss. Now that I Lift NY has placed the section of steel on the barge, TZC is able to remove the crane’s rigging and fasten the steel to the barge, making it safe for offsite transportation.

While the old bridge’s trusses are moved offsite, the “steel cage” center of the main span currently sits just south of the new bridge. The 532-foot section of steel – removed in a 27-hour operation earlier this year – is being disassembled on the river, with TZC crews separating roughly 10 million pounds of interconnected steel.

In addition to the steel, many concrete materials are also being recycled. Nearly 900 tons of material from the old bridge are being used in the state’s largest artificial reef expansion initiative under the leadership of Governor Andrew M. Cuomo.

State agencies will continue the reef program later this summer by deploying an additional 33 barges of Tappan Zee Bridge recycled materials and 30 cleaned vessels to six reef sites.

TZC plans to remove more than 300,000 tons of concrete, 46,700 tons of steel, more than 2,000 precast deck panels and 196 piers by the end of the dismantling effort.

I Lift NY will continue to assist with dismantling efforts later this year as TZC removes the old bridge’s steel substructure.

The dismantling of the old bridge allowed TZC to fully connect the eastbound span of the Governor Mario M. Cuomo Bridge from Rockland to Westchester earlier this month.

Subscribe to our monthly newsletter to receive these updates and the latest project information.