Structural contribution of glass in Saint-Hubertus Galleries

Many of the glass-covered iron and steel frames from the nineteenth and twentieth centuries now require renovation. During rehabilitation, the question arises of how to preserve built heritage while fulfilling modern standards on safety and structural integrity. In a traditional recalculation, the glass panels are considered to be dead load on the iron frame, leading to the conclusion that the original frame requires strengthening. This paper presents a calculation that takes the contribution of the glass plates into account while assessing historical glass coverings. The overall structural behaviour of the iron and glass roof of the Saint-Hubertus Galleries, Belgium, was simulated and a parameter study was performed using a finite-element software package. The original structure comprises a wrought-iron frame clad with single glass panes connected to the glazing bars with traditional linseed-oil putty. The behaviour of the original structure, the influence of the application of modern adhesives and sealants, and the replacement of single with laminated glass plates is investigated. Although building such models is time consuming, including glass panes in the model leads to lower stresses, deflections and a better buckling behaviour, even if connected with linseed-oil putty.