Home New South Wales Multiplex employs inventive methods to install cranes above the water

Multiplex employs inventive methods to install cranes above the water

  • August 16, 2023
  • by Property Australia
Sydney Fish Market project site

Multiplex has finished the intricate task of positioning three tower cranes above the water at its New Sydney Fish Market project site.

This accomplishment was achieved through the use of innovative construction techniques, carefully devised to tackle the specific challenges posed by the site’s position in Blackwattle Bay.

The upcoming Sydney Fish Market, designed by the architectural firms 3XN and BVN on behalf of the NSW Government, is set to become the largest facility of its kind in the Southern Hemisphere.

Once completed, the site will boast a waterfront promenade, ferry wharf and over 6,000 square meters of fresh public open space.

Due to the unique characteristics of the site, which is situated in close proximity to the water and subject to marine influences like tidal fluctuations, the installation of cranes and their support infrastructure demanded meticulous planning and sophisticated engineering solutions.

Paul Couani, Multiplex’s Project Manager said the first two tower cranes were installed within the waters of the Bay and before the cofferdam was closed off, which meant they were exposed to tidal changes.

“We undertook detailed planning in partnership with Marr Contracting and SMC Marine, and the complexity required four times the typical amount of time needed to complete a dry land installation.”

The process involved installing the primary foundation piles initially, followed by the implementation of bracing to offer lateral support for the grillage connection. The installation of this bracing employed divers to arrange and secure the underwater components using grouting techniques.

Multiplex Construction Manager David Maher said the earlier they installed the cranes the less impact it would have on the progress of construction.

“Because of the space required to actually erect a tower crane is significant,” he said. 

“So we had to come up with an engineered solution that enabled us to install the cranes early in the project.

“We needed the cranes installed early to accept materials being delivered to the site via barges from our materials handling yard at Glebe Island.

 “And this actually opened up the opportunity for us to prefabricate both form work shutters and precast panels off site that couldn’t have been delivered via road could only be delivered via barges because of the size of them.”

Another obstacle in devising the support structure was the stipulation of avoiding any breaches in the hydrostatic structure. To meet this requirement, structural steel plunge columns were employed to support the grillage. These columns were integrated into the design to serve as enduring support for the primary construction.

The third crane was set up subsequent to Multiplex’s drainage of a staggering 100 million liters of water from the cofferdam. This process established a watertight enclosure, creating a dry working environment suitable for the commencement of the structural construction. Despite adopting a more conventional “dry land” approach, the distinct site location mandated the use of a specialised marine barge crane that was anchored within Blackwattle Bay.

Multiplex opted for tower cranes that stand out as some of the first in Australia to utilize HVO100 renewable diesel. This type of diesel is entirely renewable and boasts a potential reduction of up to 90 per cent in overall emissions when compared to conventional fossil fuels.

Upon completion, the edifice is designed to maintain its structural integrity for a century, accompanied by energy-efficient facilities and systems that target a 30 per cent reduction in energy consumption. The project aims to secure a 5 Star Green Star rating, with the construction anticipated to conclude by late 2024.