*2.3. Material of Numerical Models*

The analysed geodesic domes were made of steel struts (round pipes) of S235 standard steel. The properties of this steel grade were: (i) Young modulus (*E*) 210 GPa, (ii) Kirchhoff module (*G*) 80.76 GPa, (iii) Poisson ratio (*ν*) 0.3, (iv) volumetric weight (*γ*) 7850 kg/m3, (v) thermal expansion coefficient (*α*) 1.2 × <sup>10</sup><sup>−</sup>5, and (vi) partial safety factor (*γM*) 1.0. The steel elements were modelled as a linearly elastic isotropic material (according to Eurocode 3 [56]). All of the struts in both analysed domes were grouped into four groups, taking into account a different cross-section (commonly used cross-section) of the elements, as shown in Table 1.

**Table 1.** Division of the analysed geodesic domes into four groups of struts.

