Concept and Design
Planning and Construction
Schlosser Holzbau GmbH
Himmelsstürmer, Landesgartenschau Schwäbisch Gmünd 2014
Length: 5.40 m | Width: 5.40 m | Height: ~ 36 m | Weight: ~ 64 t
Number of Nodes: 429 | Finite Elements: 10,262
A highlight of the 2014 State Garden Show in Schwäbisch Gmünd, Germany, is the look-out tower "Himmelsstürmer" which is almost 40 m high. It is made of approximately 176 m³ of cross‑laminated timber and consists of an inner and an outer tower.
A stairway with 209 steps in the area between the internal and external walls leads to the tower top. Visitors climbing the tower may feel like men walking to the sky, which is indicated by the tower's name.
The structural analysis of the "sky climber" was created by Andreas Wirth from Freiburg who used RFEM and the RF‑LAMINATE add‑on module.
The tower has a square base area with lateral lengths of 5.40 m. The inner tower consists of cross‑laminated timber slabs with three layers having a thickness of 12 cm. The outer tower was built with CLT elements as well. Those consist of seven layers and have a total thickness of 20 cm.
There are 123 openings arranged in the external walls so that the visitors can always enjoy the outdoor scenery. The structural components were precast to a great extent. The inner tower consists of two tubes. The outer tower was divided into three construction sections. Each section was subdivided into four L‑shaped corner elements.
The structural connection in the vertical joints is ensured by numerous fully threaded screws. They were crosswise screwed in through the vertical joints with an angle of 60° relative to the transversal direction of the slabs. In the horizontal joints, the CLT elements are connected to each other by slotted sheets and dowels.
Once the Garden Show ends, the lookout tower should be further operated by an association. Thus, visitors will still have the possibility to enjoy the incomparable view over the landscape park of Wetzgau.