Detailed FSI modeling and HPC simulation of the Olympic stadium roof in Munich under wind loading

The Olympic stadium in Munich was built for the Olympic Games in 1972. Its architecture was inspired by freefrom shapes and led to the construction of ”hanging” cable nets covered with acrylic glass plates, which constitute the main part of the roof. The main structure additionally includes pylons, masts, and cables to hold up this complex geometry. Details of the construction are described in [1]. The main focus of this work is to improve the numerical models and showcase the simulation potential for such a complex geometry, with a specific focus on the realistic modeling of the wind field (atmospheric boundary layer flow and consideration of some crucial elements of topography) as well as fluid-structure interaction (FSI, i.e. enabling the interaction between the deformations of the structure and the wind forces adapting to these changes). For the fluid domain, only the roof is explicitly captured by the mesh, in addition to the chosen topography elements. Other parts of the supporting structure are deemed to have a minimal role in the aerodynamics. Careful considerations are taken regarding the modeled geometry of the structure, these being based upon [2], data extracted from a Google Earth model, on-site measurements, and city archives. This shape represents the target geometry under self-weight and prestress. The membrane, as well as cable elements (modeled as trusses, being purely under tension), need a detailed investigation such that the correct prestress values can be determined. Initial values are based upon archive and publication data ([1]). Optimization algorithms are used in a sequential way to determine the actual necessary prestress (on an element level in the FEM context). This is to be seen as an inverse of the fromfinding procedure. An