## 2 Simplified Vulnerability Assessment Methods for Masonry and RC Building Structures
### Application of Methods of Group A
#### 3.3.2 S&C Method  
The method proposed by [PERSON] and [PERSON] [9] was applied to the 707 RC and the 228 masonry structures, i.e., 935 buildings in total excluding, thus, the buildings with'mixed' structure. The method provides ranges for the maximum PGA sustainable for the buildings, i.e., the values of PGA\({}_{c}\), in the  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Building** & **Number of** & **SPD** & **Class** & **Corrected** & **Var.\% SPD** & **Corrected** & **Var.\% SPD** \\
**Typology** & **Buildings** & & **Class—Case 1** & **Case 1** & **Case 1** & **Class—Case 2** & **Case 2** \\ \hline Irregular & & & & & & & \\ masonry & 2 & 2.3 & A\({}_{v}\) & A & 19.7\% & B & \(-\)18.1\% \\ \hline Regular & & & & & & \\ masonry & 226 & 2.1 & B\({}_{v}\) & A & 19.7\% & B & \(-\)18.1\% \\ \hline RC & 707 & 1.5 & D\({}_{v}\) & B & 18.5\% & D & \(-\)18.4\% \\ \hline \hline \end{tabular}
\end{table}
Table 11: Synthetic parameter of damage (SPD) indexes and vulnerability classes for masonry and reinforced concrete (RC) buildings according to the SAVE method (935 buildings).  
function of the building typology. Figure 8 reports the occurrence of the masonry and RC buildings within the PGA\({}_{\text{c}}\) classes defined by the S&C method.  
In Figure 9, for each building category, the average value of the PGA range, PGA\({}_{\text{c}}\), was divided by the design PGA, i.e., PGA\({}_{\text{d}}\), at the LS limit state. For masonry buildings, Figure 9 shows that the capacity was lower than the demand (i.e., PGA\({}_{\text{c}}\)/PGA\({}_{\text{d}}<1\)) in most cases (225, i.e., 98.6%). In particular, 62% of buildings had values of PGA\({}_{\text{c}}\)/PGA\({}_{\text{d}}<0.45\) and, thus, were characterized by a high seismic vulnerability, while 27% of buildings had PGA\({}_{\text{c}}\)/PGA\({}_{\text{d}}\) in the range 0.60-1.00, i.e., were characterized by medium vulnerability.  
Figure 8: Classes of peak ground acceleration (PGA) capacity according to S&C method for 935 buildings: (a) 228 masonry buildings and (b) 707 RC buildings.  
For RC buildings, Figure 9b shows that 40% of buildings had \(\mathrm{PGA_{c}/PGA_{d}}<1\), mostly within the range 0.6-0.8. Note that in Figure 9b, buildings of class CA-4, which corresponded to buildings realized after some seismic codes became mandatory (i.e., 1984 in the Campania region), were not reported since the range of \(\mathrm{PGA_{c}}\) was too wide (0.15 g \(<\)\(\mathrm{PGA_{c}}\) \(<\) 0.35 g) and the use of the average value of the range was not reliable.  
Thus, for RC buildings of class CA-4, the values of \(\mathrm{PGA_{d}}\) provided by the current code have been compared with the lower and upper limits of the \(\mathrm{PGA_{c}}\) range proposed by the S&C method, resulting in the following judgment:  
* 'Safe' if \(\mathrm{PGA_{d}}<\mathrm{PGA_{c,MIN}}\);
* 'Not safe' if \(\mathrm{PGA_{d}}>\mathrm{PGA_{c,MAX}}\);
* 'To investigate' if \(\mathrm{PGA_{c,MIN}}<\mathrm{PGA_{d}}<\mathrm{PGA_{c,MAX}}\).  
Figure 9: Ratio \(\mathrm{PGA_{c}/PGA_{d}}\) according to the S&C method for 935 buildings: (a) masonry buildings and (b) RC buildings.  
Among the 374 RC buildings of class CA-4, only 22 could be defined surely'safe', while in most cases it resulted in \(\mathrm{PGA_{c,MIN}}<\mathrm{PGA_{d}}<\mathrm{PGA_{c,MAX}}\) and, thus, more detailed analyses should be carried out.