# Design Proposal for Masonry Infill Walls Subject to Seismic Actions
## 4 Comparison of the Experimental Results with Design Standards
### Capacity
\begin{table}
\begin{tabular}{c c} \hline \hline
**Standard** & **Analytical Solution** \\ \hline FEMA 273 [21] & \(q_{in}=\frac{0.27^{\prime}_{in}\lambda_{2}}{\left(\frac{\kappa_{out}}{\kappa_{ int}}\right)}\times 144\) \\ MSJC [20]/Seah and Dawe [7] & \(q=4.50f_{in}^{0.75}l_{in}^{2}\left(\frac{\kappa}{\kappa_{in}}+\frac{\beta}{ \kappa_{out}}\right)\) \\ FEMA 306 [22] and [PERSON] [10] & \(q=\frac{2f_{in}}{(1)}R_{1}R_{2}\lambda\) \\  & \(q=\) \\ [PERSON] et al. [11] & \(\frac{8}{k!}\left\{M_{sp}[(l-h)+hln(2)]+M_{qh}\left(\frac{\kappa_{out}}{ \kappa_{out}}\right)ln\left(\frac{l}{l-\frac{\kappa}{2}}\right)l\right\}\) \\ [PERSON] [15] & \(q=\frac{f_{out}}{\left(\frac{\kappa_{out}}{\kappa_{out}}\right)}R_{1}R_{2} \lambda\left[0.77C_{f}\left(\frac{l}{l}\right)+0.34C_{f}\right]\) \\ EC6 [28] & \(q_{lat,d}=f_{d}\left(\frac{l}{l_{t}}\right)^{2}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Analytical solutions used to compute the out-of-plane capacity of the infill walls. the interior infill walls, with an error of 51%, and a good correlation for the exterior ones, underestimating the capacity by 16%. Figure 14 presents the results of models 2 and 3, as the parameters used in the analytical solutions (thickness/height of 11.3, geometry, type of units and mortar, position, etc.) are the same for both models. Even though the results for model 3 are only presented until stage 3, the path followed by the two models was similar. Model 3 was able to withstand higher out-of-plane forces, and it was assumed that the maximum force recorded during the last stage of model 2 was the capacity for both bed joint reinforced and plaster reinforced infill walls. Figure 13: Standard and experimental out-of-plane capacity comparison for model 1. Analytical solutions overestimated the out-of-plane capacity of the solid infill walls for models 2 and 3. One justification might be that the assumption that these walls were imminently in danger of collapse was incorrect, and the recorded out-of-plane load did not correspond to the experimental capacity of the infill. The standards that presented the best results for model 1, which were FEMA 273 [21], FEMA 306 [22] and EC6 [28], overestimated the capacity of the solid infill wall by 30%, 53% and 53%, respectively. [PERSON] [15], the MSJC [20] and [PERSON] et al. [11] overestimated the results by 9%, 36% and 198%. Contrary to what was observed in model 1, the presence of openings, in the transversal direction, had a clear influence on the out-of-plane capacity of the infill walls. Therefore, all the standards overestimated the out-of-plane capacity of infill walls in that same direction, ranging from 149% to 609%. In the longitudinal direction, the presence of openings did not affect the results, and except for [PERSON] et al. [11], which overestimated the capacity by 175%, other analytical solutions underestimated the experimental results, with EC6 [28] and FEMA 306 [22] providing the best results by underestimating the capacity by 10%. It should be noted that the maximum out-of-plane load recorded on the longitudinal walls with openings was higher than the load recorded for the solid infill walls of the same direction and, particularly in model 2, the ground floor infill walls with openings were on the verge of collapsing, while the solid walls had less damage. This might lead to the assumption that the recorded values for the longitudinal infill walls with openings were in fact the maximum capacity, while the solid walls could endure a higher out-of-plane load, hence the underestimation by most analytical solutions. Other aspects that might contribute to these discrepancies are the in-plane damage and the possible effect of the restraint of boundary conditions and arch effect, due to the slenderness and openings. Figure 14: Standard and experimental out-of-plane capacity comparison for models 2 and 3.