*2.4. Description of Numerical Analysis*

The DLUBAL RFEM 5.21.01 (2020, Dlubal Software GmbH from Tiefenbach, Germany) numerical program was used to analyse the effect of seismic excitations of the geodesic domes. This program is based on the finite element method. This method enables the determination of the maximum value (e.g., displacement or acceleration) in a given node of a finite element. The mentioned numerical program (RFEM) is widely used by engineers all over the world. It gained its popularity thanks to extensive specialised modules. In this paper, the RF-DYNAM PRO 5.21.01 (2020, Dlubal Software GmbH from Tiefenbach, Germany) module was used for dynamic analysis of the structure response. In the analysed numerical models, the size of the finite elements did not exceed of 0.2 m. The supports of dome were modelled as rigid. The purpose of such modelling of the supports was to obtain the maximum response of the dome structure to the given excitation. This proposition of support was commonly used in engineering practice, e.g., by Chmielewski et al. [57], Tabatabaiefar and Massumi [58]. In a geodesic dome, the Soil–Structure Interaction (SSI) effect can be omitted, because in these structures, there is no effect of: (i) second order, (ii) massive, (iii) slender tall structure, (iv) or soft soil from Eurocode 8 [59].

#### *2.5. Seismic Excitation*

In order to assess the effect of seismic response on geodesic domes, four different seismic records were used, i.e., (i) Ancona, (ii) Denizli, (iii) Friuli, and (iv) Kilini. The Ancona record (Italy) comes from the Genio-Civile station on June 14, 1972. It was characterised by ground acceleration equal to −3.740 m/s<sup>2</sup> (Figure 4a) and duration of 7.76 s. The second record Denizli (Turkey) was recorded at the station Denizli-Bayindirlik ve Iskan Mudurlugu and dates from August 19, 1976. For this recording, the ground acceleration value was −3.387 m/s<sup>2</sup> (Figure 4b); this recording lasted 17.31 s. Another record came from Italy (Friuli), exactly from the Somplago-Uscita Galleria station on September 16, 1977. The maximum value of ground acceleration during this earthquake was −1.870 m/s2 (Figure 4c) and lasted 16.30 s. The last weakest record came from Kilini (Greece) at Vartholomio Residence station on October of 31, 1998, and its maximum ground acceleration was 0.714m/s<sup>2</sup> (Figure 4d) in 16.18 s.

**Figure 4.** The most intensive component of seismic excitations (x-direction): (**a**) Ancona (Italia), (**b**) Denizli (Turkey), (**c**) Friuli (Italia), (**d**) Kilini (Greece).
