Chartered Institute of Building Magazine of the Chartered Institute of Building


Video | 8,000t cantilever hoisted into place

28 September 2020

An 8,000t tonne, 227m-long cantilever whose structural steel weighs more than the iron in the Eiffel Tower, has been lifted into place to join together two towers in Dubai.

The Link forms part of develop Ithra Dubai’s “One Za’abeel” mixed-use project in Dubai.

Main contractor Alec Engineering and Contracting embraced 4D modelling with Bentley’s Synchro for the project, which it was claimed knocked 70 days off the programme and saved £12.5m.

One Za’abeel comprises two tall podium-mounted towers on either side of a busy thoroughfare, next to the Dubai World Trade Center Exhibition Halls. The towers are now linked 105m up by a steel bridge which juts 66m into thin air. The link itself is 227m in length, a horizontal skyscraper in its own right.

The main bridge section was constructed at podium level while the towers were being built and, as its length grew, Alec slid it in scheduled movements across the busy road. It was strand-jacked into place as part of the largest lift to date in the Middle East. The bridge structure will be finished as an interior space with an infinity pool on its roof.

Dr. Fadi Jabri, executive officer at Japaenese architecture firm Nikken Sekkei, which was responsible for the concept and design of the two-tower structure and the cantilever said: “Designing the world’s longest-occupied cantilevered building was an ambitious challenge in itself. However, designing an offset cantilever between two towers, 100 metres above a busy highway, was a challenge of ingenuity and imagination none of us had ever faced before.”

“The lifting process was incredible. The initial lift on the 18th August was a mere ten centimetres to check for cable stretching and the building’s reaction to the strain – all works will be halted so we could listen to how the building would react. A further one metre lift took place a week later, followed by the main event, three days later – the final 100 metre lift into place.”