The thyssenkrupp Test Tower in Rottweil designed by Werner Sobek is literally raising the bar for lightweight technology as the testing grounds for revolutionary technologies like the rope-less MULI elevator.
The impressive project was controversial in the beginning. Would a huge tower disrupt the quaint and historic image of Rottweil? In the end, the people and town council made a bold decision and can now be proud of a new future oriented attraction in their city. The spectacular 246 meter high structure serves as a testing and certification facility for elevator and lift innovations built by thyssenkrupp, making a vital contribution to reducing development times for future skyscrapers as well as skyscrapers currently under construction around the world. Despite its impressive height, the building maintains a sleek and sophisticated appearance. Architects Werner Sobek and Helmut Jahn covered the outside of the concrete shaft with a fiberglass exterior and included the highest observation platform in Germany at 232 meters. The tower is a triumph of lightweight design and adaptive structures in architecture. Inside, the testing facility also houses the revolutionary MULTI elevator – the world’s first lift system which allows more than one elevator cab in the same shaft and can move both vertically and horizontally.
The state agency for lightweighting is presenting this innovation as its ThinKing for July 2017. Leichtbau BW GmbH presents this distinction each month to promote innovative products and services in the Baden-Württemberg lightweighting sector.
Rottweil is the new center of the technology world – at least when it comes to tower construction and elevator innovations. The idyllic small town between the Black Forest and the Neckar-Alb region was founded by the Romans nearly 2,000 years ago. It’s historic city center has remained largely unchanged since the 16th century. Visitors from all over Europe flock to Rottweil to enjoy the beauty of this fabled “city of towers”. In addition to several art galleries and cultural events, visitors can now also look forward to what could be one of the most impressive views in Germany.
Rottweil is now the home of a new modern elevator tower whose architecture offers a new dynamic to the historical towers of the medieval city center. After a long search, thyssenkrupp Elevator selected the small town as its choice location because of the nearly 10,000 engineering students studying at the surrounding colleges and universities.
Groundbreaking possibilities – the revolutionary rope-less MULTI elevator
The 246 meter high structure serves as a testing and certification facility for innovative elevator systems which makes significant contribution to reducing development times for future skyscrapers and skyscrapers currently in construction around the world. With twelve shafts and travel speeds of up to 18 m/s, the tower offers new possibilities for meeting new development challenges. Three of the shafts are used for the revolutionary MULTI elevator system – a rope-less elevator systems which allows several cabs to be used in the same shaft moving both vertically and horizontally thanks to linear motor technology.
A prime example of lightweighting potential
The Test Tower itself is an example of the potential of lightweight technology and adaptive structures in architecture. The building combines an optimal supporting structure with a multifunctional building envelope which plays a key role in reducing thermal loads and stress caused by wind. Technological innovations such as new elevator systems will enable new skyscrapers to be built with thinner cores and with significantly less mass.
The core of the load bearing system in the town consists of a steel reinforced concrete tube. This core has an outside diameter of 20.8 meters. A base structure with a diameter of 48 meters offers additional horizontal bracing. Wind tunnel experiments showed early in the structure’s development that the core’s tendency to sway from side to side could not be completely eliminated with the exterior textile envelope alone. It was therefore decided to use a suitable absorption system to prevent sideways movement. A pendulum system was selected which is housed in a hollowed area of the tower at 200 meters above the ground and suspended from nine meter cables. Concrete slabs act as the pendulum mass. They are attached to a steel frame and placed in their correct position on the steel cables via hydraulic presses.
World’s only skyscraper that can be intentionally oscillated
In its normal state, the pendulum is passive and only reacts to wind induced oscillation. However, the pendulum can also be used to intentionally make the building swing. This allows the simulation of different wind conditions. Horizontal movement of up to 200 mm at the top of the tower can be induced. The Test Tower is therefore the first building in the world that can be intentionally oscillated in order to simulate wind stresses.
Architect and engineer Werner Sobek is convinced that architecture suited to the needs of the 21st century can only be created achieved through a “profound change in our way of building”. “An important element in this is ultralightweight construction. Only this enables radical reductions in mass and energy requirements such as in the production and transportation of concrete.” Werner Sobek is guided by the Triple Zero Concept – that buildings should only consume as much energy as they produce themselves from sustainable resources, they should not create any emissions, and they should be made entirely of recyclable materials. According to Werner Sobek, “Future construction must be simultaneously resource efficient and usage oriented.”
This view is shared by Dr. Wolfgang Seeliger, managing director of Leichtbau BW GmbH. “In order to be able to satisfy society’s future needs – such as affordable living space – lightweighting will be essential. Our resources are finite. Though hard to believe, we are even running out of building sand. This is where entirely new building concepts come into play. Lightweighting principles can help bring together completely different functions such as mobility and building structures in urban systems. New elevator technologies like the thyssenkrupp Test Tower for example are now turning horizontal transport in building facades into plausible reality.”
About Leichtbau BW GmbH
Leichtbau BW is a fully state owned company representing a network of nearly 1,550 companies and more than 200 research institutions covering every aspect of lightweight technology. Leichtbau BW GmbH serves as a networking platform for private companies and research institutes to facilitate further innovation in lightweighting. Leichtbau BW promotes and markets lightweighting innovations and initiates education and training programs.
About the Werner Sobek Group
Werner Sobek is globally renown for its engineering, design and sustainability competence. The group companies are present in Stuttgart, Dubai, Frankfurt, Istanbul, London, Moscau and New York. The hallmarks of Werner Sobek include first-class design guided by excellent engineering and innovative concepts for minimizing material and energy requirements. Established in 1992, the company has more than 300 employees working with every type of building structure and material. The rim specializes in high-rise construction, façade design and sustainability consultation.