## 3 Research, Results, and Discussion
### Seismic Loss of Steel Ordinary Moment Frames
Figure 10: Normalized median repair cost of 15-story steel OMFs at SLE hazard level: (a) W0-OMF; (b) W44-OMF; (c) W51-OMF. wind loads. However, the repair costs for the lower stories are higher for the W0-OMF than for the W44-OMF and W51-OMF. Figure 11 shows the repair costs for the DBE hazard level. As shown in the figure, the repair costs associated with the NSTR-D is also dominant, as observed for the SLE hazard level. More repair costs for DBE hazard level are required than those for the SLE hazard level. For the DBE hazard level, the W44- and W51-OMFs have 12% and 39% larger repair costs than the W0-OMF, respectively. The contribution of STR on the repair costs for the DBE hazard level becomes more significant than that for the SLE hazard level. It is noted that NSTR-A did not have a significant effect on the repair costs associated with STR and NSTR-D. This is because the peak floor acceleration (_PFA_) is small in the steel OMFs designed for the SDC level of \(C_{max}\) or lower. To evaluate seismic loss for all limit states according to \(im\), normalized expected seismic loss is plotted in Figure 12, where the horizontal and vertical axes represent the spectral acceleration normalized to the spectral acceleration corresponding to the maximum considered earthquake (\(S_{MT}\)) and the expected seismic loss (\(EL\)) normalized to the total replacement cost, respectively. Figure 13 shows the contribution of each limit state (repair, demolition, and collapse limit states) on \(EL\). This figure shows the contributions of each limit state on the expected seismic loss according to \(im\). As shown in Figure 12, the \(EL\) values of the W0-OMF for individual limit states are less than those of W44- and W51-OMFs irrespective of \(im\). The W51-OMF has larger \(EL\) values for individual limit states than W44-OMF. This indicates that the seismic loss could increase when wind loads are considered in the design. As mentioned earlier, the concentrations of lateral displacement in the upper stories for OMFs designed with consideration of wind loads cause a rapid increase in the maximum \(SDR\) in the upper stories, which not only  
Figure 12: Normalized expected seismic loss of 15-story steel OMFs: (**a**) W0-OMF; (**b**) W44-OMF; (**c**) W51-OMF. Figure 13: Composition ratio of repair, demolition, and collapse for \(EL\) of 15-story steel OMFs: (**a**) W0-OMF; (**b**) W44-OMF; (**c**) W51-OMF. accelerates the damage of structural and nonstructural components but also causes an increase in \(RIDR\) and an increase in the probability of sideway collapse. The \(EL\) of the W44-OMF is at least 7% larger than that of the W0-OMF. The probability of collapse and demolition limit states rapidly increases with an increase in \(im\). The \(EL\) value increases up to 25%. For the W51-OMF, the \(EL\) value increases by at least 50% as compared twith that for the W0-OMF. The largest increase in the \(EL\) value is 78%. Figure 13 shows the contribution (%) of repair, demolition, and collapse to \(EL\) as a function of \(im\). As seen in this figure, seismic loss associated with the repair limit state is dominant on \(EL\) at low hazard levels. However, the contribution of seismic loss associated with demolition and collapse grows with an increase in \(im\). As shown in Figure 6, OMFs experience significant damages in few stories and collapse. Therefore, the loss associated with demolition and collapse surpasses that associated with repair when \(im\) exceeds the MCE hazard level. For \(im\) corresponding to the MCE hazard level (\(S_{MT}\)), seismic loss associated with demolition, and collapse limit states become more than 50% the total \(EL\). The contribution (%) of demolition and collapse on \(EL\) is the largest for the W51-OMF and is the least for the W0-OMF. This observation can be expected because OMFs designed with consideration of wind loads have higher seismic risk than corresponding OMFs designed without the consideration of wind loads as described in Section 4.