## 3 Research, Results, and Discussion
### Seismic Loss of Steel Ordinary Moment Frames  
In this study, the effect of wind loads on the seismic performance of steel OMFs was investigated. To achieve the research objective, the seismic loss estimation was conducted according to FEMA P58 [30]. In seismic loss estimation, the various levels of damage states for structural and nonstructural elements should be considered. As noted that in previous sections, collapse limit state is only considered to evaluate the seismic performance of OMFs, which may overestimate the seismic performance [49]. Three limit states are considered to evaluate the seismic loss: (1) the limit state, in which damage to structural and nonstructural components occurs and results in repair costs (Repair); (2) the limit state in which collapse does not occur but requires demolition and reconstruction due to severe damage (Demolition); and (3) the limit state in which collapse occurs due to earthquake (Collapse). Considering each limit state, the total expected seismic loss for a specific ground motion intensity measure (\(im\)) in the building (\(E(L_{T}|im)\)) can be evaluated based on the following equation proposed by [PERSON] and [PERSON] [50]:  
\[ \begin{array}{c}E(L_{T}|im)=E(L_{R}|R,im)P(R|im)P(NC|im)+\\ E(L_{D}|D,im)P(D|im)P(NC|im)+E(L_{C}|C,im)P(C|im),\end{array}  \tag{4}\]  
where \(E(L_{R}|R,im)\), \(E(L_{D}|D,im)\), and \(E(L_{C}|C,im)\) are the expected seismic loss associated with repair, demolition, and collapse limit state at specific \(im\), respectively. In this equation, \(P(C|im)\) is the probability that collapse occurs at a given \(im\); \(P(NC|im)\) is the non-collapse probability [\(1-P(C|im)\)]; and \(P(D|im)\) is the probability of occurrence of the demolition limit state, which is defined using residual inter-story drift ratio (\(RIDR\)) [50]. The seismic loss required to repair structural and nonstructural component damage caused by a ground motion was calculated according to FEMA P58 [30]. A reconstruction procedure is required to restore the structure experiencing collapse. For the demolition limit state, costs are required for the demolition of the building, the removal of debris, and the reconstruction to restore the performance of the building. In this study, the seismic loss associated with demolition limit state is assumed to be equivalent to 125% of the total replacement cost [30]. Therefore, the expected seismic losses associated with demolition and collapse limit states are assigned as 125% and 100% of the total replacement cost, respectively. Individual damage states and repair costs for structural and nonstructural components are defined according to FEMA P58 Vol 3 [51]: supporting electronic materials and background documentation [51]. The total replacement cost of the model buildings was assumed to be 2691 USD per square meter [52]. The quantities and types of structural components considered in this study are briefly summarized in Table 3, and the quantities  
Figure 8: Story drift ratio (\(SDR_{i}\)) in the elastic response range: (a) 15—story W0—OMF; (b) 15—story W51—OMF. and types of nonstructural components are defined using normative quantity estimation tool provided by FEMA P58 [51]. The expected annual loss (\(EAL\)) can be calculated using \(E(L_{T}|im)\) (Equation (4)) and the seismic hazard curves representing the frequency of occurrence of a specific \(im\) (\(\lambda_{im}\)). To construct the seismic hazard curve, the OMFs are assumed to be located at 2393 E Tropicana Ave. in Las Vegas, NV (\(36.099^{\circ}\) N, \(-115.119^{\circ}\) W), which used a similar design spectral acceleration as in the seismic design for OMFs. The hazard curve is obtained from the USGS unified hazard tool ([[https://earthquake.usgs.gov/hazards/interactive/](https://earthquake.usgs.gov/hazards/interactive/)]([https://earthquake.usgs.gov/hazards/interactive/](https://earthquake.usgs.gov/hazards/interactive/)), accessed on 15 February 2022).