Crews Manning Structural Steel in NYC Get Boost


Workers tasked with erecting the structural steel for the nearly 70-story One Manhattan West in New York City are getting a little bit of a boost.

Engineering New-Record talked to folks working on the site from Metropolitan Walters LLC about the 900-ton, six-story, hydraulic steel-mesh cocoon that’s aiding workers.

“This is a game-changer,” says Steve McAward, main superintendent for steel erector Metropolitan Walters LLC. “Other cocoons I have dealt with are a nightmare. This one is push a button and go.”

The Project

One Manhattan West is the pinnacle of an eight-acre, six-building mixed-use development in NYC’s new Hudson Yards district.

The 67-story, 2-million-square-foot office building is slated to be completed in December 2019, and already has tenants such as the National Hockey League, which plans to move its headquarters there.

“I had gotten this job [for One Manhattan West], and the owner said we have got to put a cocoon on it,” David Pisacrita, co-owner of Metropolitan Walters, told ENR. “But I said, ‘Let’s do something beneficial that isn’t going to add to the work we have to do.’”

The structure supports the workers as they’re putting One Manhattan’s steel in place. Once several floors are complete, the cocoon retracts its walkways, activates its hydraulic cylinders and jacks itself up to the next tier of floors.

Metropolitan Walters went with the Self-Climbing Kokoon from Italy-based Despe S.p.A., which actually specializes in demolition.

Walters workers met with Despe engineers in Glasgow, Scotland, to cover what was needed out of the system for One Manhattan.

“I said, ‘We need it to withstand 35-mile-per-hour winds. We need 25 pounds per square inch. And we couldn’t tie into the corner columns, so would have to cantilever,” Pisacrita told ENR.

While developer Brookfield Properties did suggest the use of a cocoon, Henry Caso, the head of construction for the whole Manhattan West project, said that he was surprised at the partnership with Despe because of the cost.

However, Pisacrita said that though the system cost more up front, the team has already saved money in time and labor costs, in addition to the reinforcement of the structure that would’ve been necessary with other cocoons.

Haso says if the Kokoon is rendered successful on this project, it will be used on other Manhattan West structures. He also says that he predicts the system could be used for other parts of the industry including fireproofing and curtain wall installation.


Tagged categories: Building Envelope; Commercial Construction; Condominiums/High-Rise Residential; EMEA (Europe, Middle East and Africa); North America; Structural steel

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