By Colin Foreman
Hydraulic formwork system will see the structure rise by one storey every week. A total of 154 storeys are planned, and are scheduled for completion by 2007.
Doka has started work on the main formwork package on the US $3.2 billion Burj Dubai — the world’s tallest new tower.
The firm saw off competition from German rivals Hunnebeck and Peri to take the prestigious contract.
The Doka system will be a key element of the tight construction timetable, which aims to add one storey to the structure every week over the next two years.
General manager Geir Jensen, said: “As with all contracts of this size, the equipment is supplied as a sell and buyback contract.”
According to the firm, the complicated groundplan of the building will be one of the key formwork engineering challenges.
It is estimated that 180 pouring and climbing steps will be required before the reinforced construction is complete.
The Doka automatic climbing formwork is designed to withstand extreme wind speeds of over 200 km/h, and is completely enclosed in a steel grille to provide the greatest possible safety for the crew at these dizzying heights.
Often varying from one floor to the next, the complicated groundplan of the building is one of the key formwork-engineering challenges in the construction of the shaft core and walls of the three wings of the building.
No fewer than 180 pouring and climbing steps will be required before this reinforced concrete construction can be completed. For each of these sections, around 5000 m² of Doka wall formwork Top 50 will need to be raised hydraulically by 227 automatic climbers.
A spokesman for the Austrian formwork specialist said: “The extremely tight construction schedule necessitates an ingenious, streamlined utilisation plan.”
Designed by the American architecture firm of Skidmore, Owings & Merrill, the Burj will feature a 575 m-tall reinforced concrete shaft core, followed by a steel construction, the exact height of which has yet to be finalised.
The height of the sykscraper is being kept a closely guarded secret by developer Emaar.
The formwork concept — developed by Doka in collaboration with the contracting JV of Samsung, Besix and Arabtec — envisages climbing steps being taken independently of one another in six separate zones, with work on the wing walls proceeding two to three storeys behind the central shaft core.
‘De-linking’ the in situ pouring operations from one another in this way (by dividing up the work into six mutually independent zones) makes it possible to construct the typical storeys of the structure in a three-day cycle.
A total of 154 storeys are to be formed and poured in this way. They are scheduled for completion by the end of 2007.
It is believed that this will establish a new world record, not only for the contracting joint venture, but also for Doka.(see full story on page 18)