| City, Country | Erfurt, Germany | |
| Year | 2018–2021 | |
| Client | City of Erfurt | |
| Architect | SCHULITZ Architekten | |
| Services | Structural Engineering | |
| Facts | Height: 18.7 m | Length: 27 m | |
As part of the refurbishment of the ancient Petersberg Citadel in Erfurt for the Bundesgartenschau 2021 (National Horticultural Show), a competition for a barrier-free access to the fortress was launched in 2016. The winning Design Team proposed a free-standing 14m high lift-tower in steel with two connecting lightweight steel bridges to the fortress.
The classification of the Petersberg Fortress as a cultural monument and the resulting requirements and restrictions from the preservation order posed a particular challenge in designing the support point for the footbridge on the fortress wall. The structure of the lift tower consists of two truss girders and two Vierendeel girders—the tower cantilevers from the ground to minimise horizontal loads on the fortress. For the same reason, the walkways were designed to be slender and filigree, bringing a relatively small additional vertical load to the centuries-old stonework.
