Testing for individual approval of a vault roof with in-plane loades glass panes

Abstract

At the IASS conferences in 2007 [1] and 2008 the concept and testing results of a sustainable and transparent roof construction were presented. These transparent space grid structures base on a double layer grid in which all bars in the upper layer, the compression layer, are replaced by glass panes. The glazing is part of the primary load bearing system and transfers significant in-plane forces. In 2007 the first realisation project using this new concept was launched and will be finished this year. With a dimension of 13.5 m x 21 m and an arch rise of 3.50 m it covers the courtyard of one of the Berlin palaces. The design process was attended with extensive testing to obtain an individual approval. This contribution describes the testing at single panes and the full-scale arch of 13.5 m span necessary for the individual approval of the building authorities. Plastics for the in-plane load application into the glass edge and their creeping behaviour were investigated in first tests. The stability behaviour against glass pane buckling was tested at relevant load combinations and the post breakage robustness and the walk-on ability of the overhead glazing ensured by suitable test. Load bearing tests with a total load of 13 tons were conducted at one 13.5 m arch and finished the test series. The successfully finished testing is the basis for the individual approval and the realisation of the roof construction within the next month.