Lookout Tower on Rügen Island, Germany
Customer Project
In May 2013, German Chancellor Angela Merkel inaugurated the Rügen natural heritage center in Prora. The highlight of the 4,659-acre natural heritage area on the Baltic Sea island of Rügen is the 131-foot-high "Nest Tower". It is the third tree tower that WIEHAG GmbH has built.The tower stands at a height of more than 131 feet above sea level. Visitors are thus given a breathtaking view of the landscape from a height of over 262 feet.
Structural Engineering |
Structural Analysis and Timber Tower WIEHAG GmbH Altheim, Austria www.wiehag.com Structural Engineering Office Ing.-Büro Wolf GmbH, Passau, Germany |
Architect |
Architect Josef Stöger, Schönberg, Germany stoeger-koelbl.de |
Client |
Erlebnis-Akademie AG, Bad Kötzing, Germany www.eak-ag.de |
Model
Construction of the Tree Tower
The structure of the tower consists of an outer ring made of 12 vertical glulam beams. They are arranged with rotational symmetry and set up with an angle difference of 30° each, thus forming a polygonal, spatial structure.
The columns are supported by means of steel girders on single foundations. The tree tower is stabilized by a close-meshed net of diagonal steel members as well as horizontal ring structures.
The upper third of the tower was fitted with 12 glulam arcs to make it look like an eyrie. The arcs are fastened to the cantilevered steel platform at the top and to the glulam columns at the bottom. The outer diameter of the timber tower is approximately 79 ft; in the area of the "eyrie" it is about 118 ft.
Connected to the observation tower is a 1,367-yard-long walkable treetop path that winds through the treetops at a height of 13 to 56 ft. The path is also the entrance to the tower. In order to reach the viewing platform at the top of the tower, visitors have to enter the 656-yard-long spiral structure inside the tower.
The platform consists of steel cantilevers protruding outwards that connect to the timber columns, and between them longitudinal timber beams with planking.
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New
Saving Models as Blocks in RFEM 6
In RFEM 6 it is possible to save selected objects, as well as whole structures, as blocks and reuse them in other models. Three types of blocks can be distinguished: non-parameterized, parameterized, and dynamic blocks (via JavaScript). This article will focus on the first block type (non-parameterized).

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Timber Design | Strength and Stability | Cross-Section Resistance Features
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