Exceptional Limmat Tower
Many different corners yet shaft formwork set up and stripped quickly
Data & Facts
- Residential and commercial high-rise building complex with 107 appartments on 25 levels
- Halter Entwicklungen AG, Zurich/CH
- Huggenbergerfries Architekten AG, Zurich/CH
- Priora AG, Kloten, Switzerland
- Subcontractor structural works
- BAM Swiss AG, Basel
- MEVA systems and solutions
- Wall formwork Mammut with detachable parts at the corners to adapt to the asymetric layout
- MEVA Guided Climbing MGC with 13 climbing units
- 7 shaft platforms, 2 of them with hatches and 2 custom-built units placed next to each other
- Formwork engineering
- MEVA formwork engineering teams at headquarters in Haiterbach and in Seon, Switzerland
Outsmarting the corners while climbing
A new suburb is being developed on the outskirts of Dietikon near Zurich, Switzerland. Its comprehensive urban infrastructure will be home to 3,000 residents and 2,000 employees. Its skyline will be crowned by the impressive Limmat Tower rising 80 m and 25 levels into the sky.
The building design of the tapering tower meets the most up-to-date requirements. A detailed safety concept is in place to ensure all-round worker protection. But how do you climb shaft walls with many different corners quickly and safely? These are some of the challenges faced by the MEVA engineers.
Three lift and two staircase shafts are arranged around the pentagonal foyer area leading to the 5 appartments on each level. The shafts are being climbed with Mammut formwork panels placed on MGC climbing platforms on the outside and on shaft platforms on the inside. The crux: all the walls of the foyer area have a right and an obtuse angle on the outside. In addition, the pre-cast staircases are flown throught shafts to the floor below while the formwork is in place on the platforms.
Outsmarting the corners while climbing
The Mammut wall panels are fixed to a carriage on the MGC climbing platforms. After the pour, the panels need to be retracted from the wall and climbed to the next level in a single lift. But how? Since the climbing units are not aligned straight, they would get in each other’s way in the corner areas. The trick developed by the MEVA engineers is simple but effective: detachable wall formwork parts that are placed next to the stripping corners for the 90° angles and the special corners for the obtuse angles. When climbing, these detachable formwork parts are removed before the other panels are retracted from the walls. The special designs were built for re-use on all 25 levels, making time-consuming site-built fillers redundant for the entire project.
Solution for staircases
The shaft platforms in the staircase shafts have special hatches through which the pre-cast stairs and landing pedestals are flown in by crane to the level below. This allows the building team to adhere to the strict scheduling for all works on the levels following the climbing unit.
One split climbing platform for five corners plus placing boom
For reasons of weight and geometry, a single climbing unit was unfeasable for the foyer area with its 4.10 m long walls and five 72° corners. The solution: two separate platforms are placed next to each other with an opening for the placing boom located between them. The platforms are lifted separately, worker fall protection provided on each by a special guard rail. The guard rail is lowered for easy work access, then raised and fixed in position before the climb itself.
Climbing one level each week
The 3 m Mammut wall panels are sufficiently high to cover the 2.90 m pour on each level from the second without any extensions. The Mammut’s load capacity of 97 kN/ m² allows the walls to be poured in a single pour. One level is completed every week.
The facade of the appartement levels is defined by columns and large glass fronts, which are completed together with the slabs immediately after the core shafts and walls have climbed to the next level. Secondary platforms are not needed with the MGC units, since the climbing cones are removed from the slabs. This speeds up each lift and contributes to smooth work flow.