The Prussian Cap ceiling of the Cologne Cathedral - non-destructive investigations for the state of preservation

Non-destructive investigations of the Prussian Cap ceiling in Cologne Cathedral reveal critical design flaws that compromise its structural integrity. The study found that the 19th-century construction, intended to meet strict fire protection standards using industrially manufactured steel girders, was only designed to support its own weight without accounting for additional loads. This discovery underscores potential risks associated with the ceiling's stability, particularly in the challenging-to-access choir chapels. The research combined extensive damage analysis with historical static calculations to identify execution errors and structural vulnerabilities, providing critical insights for preservation efforts.

Hutt, S., Asgharzadeh, A., Bastgen, M., Raupach, M., & Füssenich, P. (2016). The Prussian Cap ceiling of the Cologne Cathedral - non-destructive investigations for the state of preservation. Structural Analysis of Historical Constructions: Anamnesis, Diagnosis, Therapy, Controls, 676–685. https://doi.org/10.1201/9781315616995-91