The Waldstadion Frankfurt - Germany
Lifting and tensioning of the cable roof structure for the new sports stadium
 

Scope of works performed

• Heavy lifting
• Post tensioning

CLIENT

Max Bögl Stahl-und Anlagenbau, Neumarkt

ARCHITECT

von Gerkan, Marg und Partner, Berlin

ENGINEERING CONSULTANTS

Schlaich Bergermann und Partner, Stuttgart

STRAND JACKING OPERATIONS

VSL (Switzerland) Ltd.

VSL Entity

VSL Heavy Lifting

Date

2004

Project Description

During June and July 2004, one of the most spectacular roof structures in the world was lifted into place over the newly renovated ‘’Waldstadion’’ in Frankfurt. A tremendous time pressure was on the installation works, as only the break in the football season was available to get the roof anchored in its final position. 
 
The roof consists of a double layered cable net structure, which will later be covered by a membrane. 44 radial cables are anchored on the compression ring running over a length of 709 m around the top of the stands. 35 m above the centre of the field, all 44 cables are anchored in a massive central node. Today a video cube with 10 m long sides is hanging there.
 
The 9,000 m2 central part of the roof can be retracted and folded inside the cube within 20 minutes. Because of this feature the stadium has been dubbed the biggest ‘‘convertible‘‘ in the world.
 
The lifting operation was executed in 2 stages. As a first step, the upper radial cables were pulled with 44 strand lifting units over a distance of about 30 m. Halfway through this operation a stop was necessary to install the flying masts between the upper and the lower level of the tension ring. During the whole operation cable forces and movements had to be monitored within very tight tolerances.

The equipment was then reset for the pulling and tensioning of the lower radial cables. The total pulling capacity of the entire 88 units exceeded 21,000 t. The temporary struts at the compression ring were removed when there was about 1 m left to pull. In this final stage, all 44 cables had to be pulled simultaneously within millimetres to avoid overstressing the compression ring.


More information?
Download our job report