Spearheaded by its booming capital of Doha, the Emirate of Qatar has emerged from the shadow of Dubai in recent years to successfully position itself as an attractive alternative location for the international real-estate and investment market. Vacant lots have become a rarity, and new buildings are going up almost wherever one looks. Given the rising number of overnight stays, investors are showing particular interest in high-end hotel properties.
Two such projects that are currently underway are the 22-storey Shemoukh Twin Towers, and a luxury hotel with 240 rooms and 40 exclusive apartments that is scheduled for completion in 2012. The timetable for the work on the structure shell is an extremely tight one, so a top priority on this technically demanding high-rise project was to ensure a time-optimised construction workflow with short cycle times. To execute the CIP concreting work, main contractors S.E.G. Qatar are relying on a high-performing comprehensive formwork solution from Doka – and enjoying fast construction progress. To ensure the very greatest efficiency in the construction operations, the two massive CIP concrete cores are being cast in advance of the floor-slabs using high-performing Doka automatic climbing formwork SKE50. A total of 96 automatic climbers and 640 m² of Large-area formwork Top 50 are in service here.
Extra-short assembly times and maximum safetyMore than 8000 frames of Doka’s new Load-bearing tower Staxo 40 system, as well as Staxo 100 load-bearing towers, are providing strong and effective shoring for the floor-slab formwork. The newly developed Load-bearing tower Staxo 40 stands out for being extremely easy to handle. With its optimised lightweight H-frames, Staxo 40 can be erected in half of the time that a standard single-leg system would take. Low unit weight and the small number of separate components enable the site crew to assemble each tower in a very short time.
By using the finite-element method in the constructional design process, Doka’s engineers were able to greatly reduce the weight of the Staxo 40 frame while permanently improving its strength. The results speak for themselves: a standard-version Staxo 40 frame only weighs between 15 and 24 kg and so can easily be shifted by just one person. The innovative H-shaped frame geometry and well-balanced centre of gravity are further factors which facilitate the workflows.
At the Shemoukh Twin Towers project, erection times of less than 20 minutes for the Staxo 40 towers, each 7.75 metres high, are being achieved on site by a three-man crew. The system has proved to be very safe to erect and dismantle, even at large shoring heights, thanks to its extensive safety accessories such as integrated universal U-bracket for personal fall-arrest harnesses, and platform brackets for enhanced safety at slab edges. In particular, the fact that the load-bearing towers can be pre-assembled in the horizontal greatly shortens set-up times and makes for maximum on-the-job safety. Thanks to the crane-handling-safe links between the towerframes and the integrated anti-dropout lock, the load-bearing towers can easily be lifted into position, or relocated, in just one crane cycle. “The possibility to erect the towers horizontally has given us big time savings, greater flexibility in terms of our time schedule, and a very safe way of working”, says S.E.G.’s Construction Manager Miled El Dada.
Known for its very high-load capacity, the Load-bearing tower Staxo 100 is being used to support transfer beams at a height of more than seven metres. The variable inter-frame spacing of the Load-bearing tower Staxo 100 means that it can be optimally adapted to the loads that need to be transferred, and this ensures optimum cost-efficiency. 262 rugged Staxo 100 steel frames are in service at both towers, delivering exceptionally economical and safe shoring of the heavy loads. Staxo 100 towers use built-in ladders, anchorage points for personal fall-arrest harnesses and decking units with and without manholes, thus optimising safety on the site.