## 3 Numerical Study  
The time history of the forces acting on the structure is recorded level-wise. Figure 3 represents how the structure model is split into 60 regions along the height, such that a series of force components (six per floor: three forces and three moments in a body-attached coordinate system) are made available with the intention of being transferable to the structural model for structural analysis. This defines the highest spatial resolution, meaning that at the highest detailing level, 60 floors along the height are taken into account, with six DoFs at each floor and corresponding force/moment components. Due to the time settings (total time, time step) of the computational wind flow simulation, the time resolution is set to 50 steps/s, leading to 30,000 of total time instances for 10 min, which defines the temporal resolution. The total simulation time of 10 min is deemed sufficient to capture naturally turbulent wind loading effects on structures at full scale. The reduction of the forces from each point on the surface mesh of the structure is similar in manner to what would be available from HFPI experimental wind tunnel techniques. Forces and moments are reduced to a center point, which represents the geometrical center of each fictitious floor of the considered structural model. Thus, the resulting nodal forces (on mesh nodes in flow-attached coordinates) are part of the solution of the CFD solving procedure. These values are transferred onto the structural model, which is reduced to the centers of floors and transformed into the body-attached coordinate system (corresponding to the principal axes of inertia) of the building. Numerical Study I: Comparison of a Detailed FEM Model for Structures with Low-Fidelity ParOptBeam Model  
In this study, a detailed CFD model for wind is coupled to a detailed FEM model and compared with the parametric optimizable beam (ParOptBeam) model. The same wind forces from the CFD model are used for both models. The high-fidelity model (HFM) for the case study was developed to conduct a detailed time series analysis, focusing on the wind effects on the CAARC building. GiD was used during the preprocessing stage to set up the model, which included defining the geometry, assigning structural elements, and generating a finite element mesh. The material properties were considered linear-elastic, as non-linear behavior was deemed excessive for assessing operational performance. The modeling of the structural elements is summarized as slabs  
Figure 3: Transfer of wind forces to the structure. and walls, which were modeled as thick shell elements, beams and columns as Timoshenko beam elements, and supports, which were modeled as pinned fixities at the base. Geometrical non-linearities, which impact the amplification of structural responses in tall and slender buildings, were also incorporated into the HFM. Although these effects can be ignored when displacements are minimal, it is advisable to account for them. To account for geometrical non-linearities, the beam and shell elements were modeled using the co-rotating theory [29], and the Newton-Raphson method was applied in the analysis. The co-rotating approach references elements relative to a local coordinate system rather than a global one, where total displacements and rotations are considered. This method decomposes the element's overall motion into two components: rigid-body motion and deformable motion. The inclusion of shear deformations is particularly significant for deeper beams and thicker shell elements. Thick shells may be ideal for applications like foundation plates, while thin elements may be more suitable for slabs. Incorporating shear deformation provides a more realistic approach to the HFM.