## 5 Conclusions  
Although many efforts have been made in the last years to demonstrate the influence of masonry infills on the seismic performance of RC buildings, no particular attention has been paid to the variability surrounding the mechanical properties of masonry infills and how this might affect the uncertainty in fragility and loss estimation. Even in cases where the masonry infills have been considered through simplified approaches, the variability related to the geometrical configuration, material properties, and modeling assumptions was not explicitly considered. This study dealt with the effects of epistemic uncertainty and different masonry infill typologies on loss assessment of masonry-infilled existing RC buildings. The dispersion values recently proposed in the literature were used to perform a detailed loss assessment of an Italian RC existing school building and compared with the loss values obtained with other epistemic uncertainty-based dispersion proposals available in the literature. The main conclusions can be summarized as follows:  
* The capacity curves and the results in terms of EDPs, i.e., Interstorey Drift Ratio and Peak Floor Acceleration, are strongly affected by the masonry infill variability. In addition, the dynamic properties of the building could be highly influenced by the material properties of the masonry, with a lengthening or shortening of the first period  
Figure 12: Disaggregation of the expected annual losses as a function of the non-structural components typology and the two sets of dispersion values: (**a**) completely and (**b**) partially infilled structural configurations. Figure 13: Increment of the expected annual losses ratio of MDL-1 [11] with respect to MDL-2 [16]. of vibration, also influenced by the choice of accounting or not for the presence of the openings. As such, proper identification of the material and geometrical properties of masonry infills should be made to perform a reliable seismic assessment of the building;
* In all the cases for which no information on the material properties of the infills is available, the macro-level classification presented herein could support analysts in selecting, beforehand, what models could be more representative of the actual nonlinear response of the masonry infill typology;
* Accounting for the presence of the infill openings led to a reduction of the median intensity of collapse in the range of 5 to 18% with respect to the completely infilled structural configuration. Regarding the role of accounting for the presence of openings on the EAL, it was highlighted that the EAL estimation could be underestimated or overestimated by up to 50% with respect to the completely infilled counterparts as a function of the masonry infill typologies and the typology of non-structural components. As such, the presence of openings should be absolutely contemplated in the models;
* Reliable identification and propagation of uncertainty in the collapse assessment of existing structures is of paramount importance, and consequently, the loss estimation is quite affected by the assumed epistemic uncertainty: the EALs obtained with the updated epistemic set are 1.3 to 1.8 times higher than those obtained with the previous one;
* The impact of modeling uncertainty on the EAL estimations did depend on the typology of structural and non-structural components considered in the inventory group as a function of the masonry infill type. Indeed, the differences in the EALs obtained when using the two dispersion sets are negligible for the acceleration-sensitive components and weak (type-1) and weak-to-medium (type-2) masonry infills. On the other hand, the impact of the higher dispersion introduced by MDL-2 is quite noticeable for medium and strong masonry infills.