Structural optimisation and rationalisation of the BUGA fibre composite dome

A Pavilion, manufactured using core-less fibre wound (CFW) reinforced polymers was exhibited in the Bundesgartenschau 2019 (BUGA) in Heilbronn from the 17th of April until the 6th of October 2019. The load bearing structure of this Pavilion is the latest endeavour, developed as a collaborative effort of the ICD and ITKE institutes at the University of Stuttgart. The goal of the research is to design and engineer lightweight and high-performance building components. A previous structure with the same manufacturing methodology was exhibited in 2016 at the Victoria and Albert Museum in London. The structural system of the pavilion was a dome structure covered by a transparent Ethylene tetrafluoroethylene (ETFE) membrane with steel ridge and edge cables. The structural typology was such that maximum bending moments appear at the nodes, leading to maximum forces at the connections. The dome structure was made of 60 components, each hollow in section and bone-like in shape. Due to the membrane nature of the ETFE skin, loads were unequally distributed over the dome. This paper will describe how the shape of the dome was structurally optimised in order to reduce design forces in the components as the main objective, while rationalizing the 60 different components in manageable geometries for fabrication.