Burj Dubai reaches 601 m on scheduleWorld record using Doka Formwork Technology
The structure shell of the Burj Dubai is already the tallest building on the planet. On 8th November 2007, the in-situ concreting works on the structure core were successfully completed at a height of 601 metres above the foundations. Doka Group Executive Director Josef Kurzmann congratulated the management of the contracting JV of Samsung-Besix-Arabtech on completing the structure core inside the original timetable, and thanked them for a great partnership-oriented working relationship.
Construction of the Burj Dubai – the world’s tallest building – has involved an unusually high proportion of wall-forming operations for a skyscraper. Its statically required honeycombed structural design, with many airframe-like stiffening reinforcements, necessitated the forming of 430,000 m² of wall. This meant that twice as large an area of walls had to be formed as of floor-slabs. The Doka climbing formwork system for the wing-walled structure core worked with clockwork precision, enabling a typical storey to be finished every three days.
Expedition to a height of 601 m
For the Burj Dubai project, Doka embarked on a 2 ½ year expedition leading ever upward to a final height of over 600 m. Never before in the history of formwork technology has climbing formwork been deployed over such a long period, at such a great height and under such extreme conditions. Successful completion of the in-situ concreting works on the structure core has brought Doka not only a world record but also some valuable experience of extreme situations. The architectural design, too, made some exceptionally tough demands of the formwork system. The Y-shaped, wing-walled structure core of the Burj Dubai tapers upwards, undergoing no fewer than 32 changes in layout as it does so. As early as when planning its “forming machine”, Doka had to make allowance for each of these adaptations, right down to the last detail. Separation points in the platform system enabled the formwork solution to be modified safely and reliably every time the layout changed, with only minimal impact upon the cycle time. In order for the storeys to be poured in a 3-day cycle, the system also had to be highly efficient and easy to operate. Durability was another watchword here – after all, the “forming machine” was going to have to function smoothly for several years. The sheer robustness of the Doka components astounded even experts, and meant that during all of 180 casting sections, only a single change of form-facing was needed. Says Samsung’s Project Director Kyung-Jun Kim: “As the in-situ concrete core was being built ahead of the floor-slabs, construction progress on the whole building was entirely dependent on the self-climbing Doka formwork solution. The Doka climbing formwork system functioned with machine-like precision, allowing us to complete the in-situ concrete core within the original timetable.”
Superlative safety with Xclimb 60 protection-screen systemOn this prestige project, workplace safety was also a paramount concern, of course – especially in the slab-forming operations on the storeys following behind the core. To safeguard the site crew carrying out these operations at such dizzying heights, Doka supplied its self-climbing protection-screen system Xclimb 60. This completely closes off both the storey under construction and the 3 typical storeys below it, in each case with a room-high enclosure. Says Health & Safety Manager Mohamed Moizuddin: “During the 2 ½ year shell construction phase, we didn’t have a single serious accident. As the Burj Dubai’s groundplan was designed to resemble a desert flower, it has more than twice as many outside edges as a conventional skyscraper. All of these had to be completely safeguarded, of course. Without the Doka protection screen, the risk for the crew working on the slab-forming operations would have been incalculable.” The climatic conditions encountered at the site were also extreme: The desert climate right next to the open sea causes great temperature fluctuations between day and night. These often lead to violent sandstorms with wind speeds of over 100 km/h. Conditions such as these challenged both men and materials to the limits. However, the Doka climbing formwork system was designed to cope with wind speeds of up to 200 km/h. Doka Executive Director Josef Kurzmann sums it up like this: “With this project, Doka has proved that if you use the right formwork solution, you can successfully tackle even the very biggest and toughest challenges. Our know-how, and the additional experience we gained on the Burj Dubai, make us the ideal formwork partner for the most spectacular projects on the planet.”