How high, how wide?
The Elbtower in July 2023
The Elbtower is growing and growing. At the end of July 2023, the building will have broken the 60-meter-height mark. The building’s two cores are already 14 stories high, while the ceiling of the 9th floor is currently being set in concrete.
“We are continuously working our way up,” says Marcus Eckert, division manager at Adolf Lupp construction company. “Every six to eight days, the Elbtower grows by one floor at a time, which is about four meters.” Right now, the construction workers who are building the shell are almost alone on the site. 25 Lupp employees are managing the project, plus the subcontractors who are carrying out the construction. In total, around 300 construction workers are on the site every day.
Yet the summer heat, which paralyzed much of the country, doesn’t bother people at the Elbbrücken as much. “Hamburg’s advantage is that there is always a cool breeze,” says Eckert. Special rest and break periods ensure that construction workers can recover. And if the heat gets too oppressive, they take on work inside the building.
The construction workers work staggered shifts to erect formwork and install reinforcing steel for slabs and walls during the day. “Then, starting in the late afternoon, the concrete is poured,” Eckert explains. This allows the material to set by the next day so that the construction workers can continue working.
»Every six to eight days, the Elbtower grows by one floor at a time, which is about four meters.«
For its protection from wind and weather, the formwork platform grows with the building. Once the core walls and slabs of one floor are in place, the working platform is hydraulically moved up to the next floor. Windbreaks, or wind shields, on the outside of the building provide additional safety. “When we planned the climbing formwork, we absolutely had to take into account the wind forces in Hamburg, as well as the unusual shape of the building,” explains the Lupp division manager.
After the ceiling slabs have been cast, the formwork is lifted to the next floor. In parallel, temporary floor props are erected under the slab of each floor. These props remain in the building until the individual slabs have set enough to provide the necessary load distribution. A total of 1,400 high-rise columns (24 per floor) supports the ceilings and walls; these composite columns of steel and concrete can weigh up to 10 tons.
The unique concrete for the Elbtower reaches the floors through special pumping pipes that run inside the building. Day after day, concrete mixers roll onto the construction site from the concrete plant on the opposite side of the Norderelbe. Their load is pumped to a distributor in the basement and from there goes up to become walls and ceilings. Around 60,000 cubic meters of concrete and 13,000 tons of reinforcing steel have been used so far – the equivalent of around half the total building.
Soon, however, the building will not only grow in height, but also in width. The outlines of the base are expected to be visible from mid-August. Nobu Hospitality, owned by Hollywood star Robert de Niro, will operate a hotel there. The triangular area of the atrium can already be seen.
From October, the first elements of the facade will be assembled, while the Elbtower will become ever taller. “At the end of the year, the shell will reach its next milestone at 100 meters,” says Eckert. This level, on the 23rd and 24th floors, will later house the first operation room for the high-rise’s building technology which will be crucial for the building’s operation in the future. It, too, is specially designed to ensure the ideal climate in the Elbtower.