Exceptional, says project leader Jurgen van Leeuwen about Byldis building the world’s biggest precast tower. But he doesn’t let it go to his head: this is certainly not the first high-rise construction project for the concrete company. “In the past we have supplied precast components for realised high-rise towers including the ‘Strijkijzer’ in The Hague (130-metres-high)and the Erasmus MC in Rotterdam (120 metres). The latter was also commissioned by BAM.” For expertise relating to high-rise, the company therefore does not look abroad. “In terms of construction, we trust the expertise and skill of our own engineering.”
As the construction process is primarily based on prefabrication, it is actually ‘just’ a question of stacking. The supporting facades, walls, stability cores and floors are all prefab. The number of logistical movements on the construction site is kept to a minimum thanks to an ‘optimal prefabrication’. This means that as much as possible is assembled in the factory, including natural stone, insulation, windows and installations.
“The use of a hoisting level instead of traditional tower cranes ensures that work can continue throughout the entire year without too much hindrance from poor weather conditions. ”The hoisting level is a platform with cranes that can be pushed up one floor at a time. This construction method results in an enormous building speed and significant time saving. “Limiting the construction time also means less disruption for local residents,” says Van Leeuwen.
These are not the only reasons for choosing precast. “The quality of the precast elements is particularly high because they are manufactured in a controlled environment. This is an absolute necessity for a project of this size.”
Production of the facade elements starts in June 2019. Construction is expected to begin in January 2020, at a rate of one floor a week, and will be immediately wind and watertight. The tower will be completed in 2021. BAM is the chief contractor of the project. The concrete company is supplier of precast elements for the superstructure, from the fifth up to the 59th floor.
For this project the concrete company has supplied around 770 facade elements complete with natural stone, insulation and windows; 1140 interior walls; 400 balcony plates and 250 staircases and landings. It also includes 40,000 m2 of wide slab floors. The company is also supplying and installing the windows and curtain walling of the Mid-Rise, two smaller towers of 70 metres including the plinth building.