## 3 Numerical Models  
### Selected Numerical Models  
In the current research, steel moment skeletons of 3-, 5- and 8-floor with a particular ductility were applied for investigating the seismic behavior of three models founded on soil type 2 (375 m/s \(\leq\) V\({}_{\text{s}}\) (shear-wave velocity) \(\leq\) 750 m/s). Seismic design of these three models was conducted using ETABS software and Iranian national construction codes [34]. The height of stories is 3.2 m and each of them was founded with three linear and lateral spans by the same width of 5 m [35]. In addition, corresponding columns and beams were chosen on both sides with stories undergoing similar efficiencies. Based on European standard cross sections, various kind of profiles were assumed for beams and columns,  
Figure 4: Conceptual plot showing the time intervals of strike-slip and dip-slip faulting in which the filing-step and directivity pulse are displayed together and discretely [32]. Figure 3: Conceptual plot representing the trends of the filing-step and directivity pulse for strike-slip and dip-slip faulting [32]. The following symbol is applied for the columns place in the analysis result section (in Section 4 of paper):  
Cij* is the code for position of results in the columns;  
i = story number;  
j = number of columns located in the left-hand of buildings. There are different assumptions being considered in this research. Dead (fixed) load on a building is due to the weight of constant elements including beams, floor segments, columns and walls. The fixed load is used as a monotonic distributed load parallel to each beam, column, or wall and as a surface load for the deck/segment. The magnitude of the beam and column loads equals the surface area times the material weight density. The magnitude of the wall load equals wall's thickness times the wall height times the material density. The live load is calculated based on the standard loading code. The live and live loads of 20 kN/m\({}^{2}\) and 65 kN/m\({}^{2}\), respectively [36], were applied to all stories. But different loads were applied for roofs, at 54 kN/m\({}^{2}\) and 15 kN/m\({}^{2}\), respectively [26; 37]. All models were fulfilled based on the rigid bed which was used for all stories. Elastic elements were considered for all beam and columns in OpenSees software which has been employed for modeling these structures. Bilin non-multi linear materials were used in order to describe the behavioral properties of elements [26]. The Krawinkler panel zone model was selected in this research (see Figure 6). The parameters of the Bilin material were obtained based on the study by [PERSON] and [PERSON] [38]. Panel zone distortion occurs mainly in shear because of contrary moments in the columns and beams. Panel zone modeling is explicitly performed through the method described by [39]. In this approach, modelling of the panel zone is performed in a rectangular pattern with eight very stiff elastic beam-column components. Shear deformation in the panel zone is shown by one rotational source (Figure 6). The Bilin material is defined as the corrected deterioration model of Ibarra-Medina-Krawinkler with a bilinear disturbed response. Figure 7 presents the components of the Bilin material. [PERSON] and [PERSON] presented the relationships between the variables [38]. The 3-, 5- and 8-story buildings have fundamental periods equal to 0.48, 0.91, and 0.78 s, respectively. Figure 6: Conceptual display of an ordinary panel zone [40]. For simulating the nonlinear behavior of the investigated structures, their modeling was performed by using elastic beam-column components in association with rotational sources. According to the corrected IMK (Ibarra-Medina-Krawinkler) deterioration approach, the sources are supposed to represent a bilinear hysteretic reaction. Rotational springs are employed to represent the nonlinear behavior of moment frames using the concentrated plasticity concept.