Trident and ULMA raise ‘tallest skycraper in Brooklyn’

By Leila Steed27 September 2021

9 Dekalb Ave Brookly, New Yorkn Measuring 325m tall and comprises 73 floors, 9 DeKalb Ave is said to be the tallest building in Brooklyn. ©ULMA Construction

US-based Trident General Contracting is using a variety of formwork, shoring, climbing, and safety systems for the construction of a 325m tall skyscraper in Brooklyn, New York, US.

Known as 9 Dekalb Avenue, the residential tower is being built on behalf of JDS Development.

It was designed by SHoP Architects and comprises 425 apartments, 150 condominiums, an outdoor terrace and a rooftop swimming pool. 

To construct the tower, which will rise 73 storeys into the air upon completion, Trident is using the newly updated telescopic HWS perimeter safety screens from specialist access equipment provider, ULMA Construction

ULMA said, “The exceptional height and constant change in shape of the building required this technical solution.

“The other big challenge of this job were the three transfer levels on floors 34, 51, and 74, with thick slabs supporting solid perimeter walls designed to transfer both vertical and lateral load.”

The HWS system was used to brace the wall formwork prior to pouring the concrete. According to ULMA, this meant that Trident could proceed without the use of a crane.

9 Dekalb Ave Brooklyn, New York The HWS was chosen as the most suitable technical solution for the new tower, owing to its height and constantly changing in shape. ©ULMA Construction

The cores were made with the RKS Rail Climbing Formwork, which ensures safe climbing at height due to the rails attached to the walls.

“It is versatile and can be lifted by a hydraulic mechanism or without crane assistance,” said ULMA.

Alongside the RKS Rail Climbing formwork and HWS system, Trident also used the MEGALITE handset panel to erect the skyscraper’s walls and columns. 

According to ULMA, the product can support a concrete pressure of up to 1250psf and enables walls measuring more than 2.43m (8ft) in height to be installed. 

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