SEISMIC VULNERABILITY ASSESSMENT OF COMPLEX HISTORICAL MASONRY AGGREGATES WITH INTERACTIONS BETWEEN STRUCTURAL UNITS

Large scale complex historical buildings, such as palaces or historical city centres, are usually composed of aggregates that were built or connected in different phases. Consequently, under seismic action, there will be an interaction between the buildings that needs to be taken into account when performing their seismic vulnerability assessment. As seen by past seismic events, historical masonry aggregates present a high vulnerability to seismic action. In this paper, different types of connections will be modelled between adjacent bodies and their effects on the global seismic response will be studied. The National Palace of Sintra, Portugal, an excellent example of large-scale irregular complex rubble stone masonry historic buildings, will be considered as a case study. The Palace is composed of several units built during different time epochs, starting from the XIII Century until the XVII. A collection of the different cases of connections between the units presented in the Palace will be organized and delivered here, according to the presence of different heights and/or floor levels, walls that are connected in same direction or perpendicular to each other, and other irregular cases that were found. Using some units of the Palace as an example, the modelling approach considered for each type of interaction between the units by means of EFM will be described. The results of the global seismic assessment carried out with nonlinear static analyses will be presented and discussed. A comparison regarding the models with and without considering the connections of the adjacent buildings will also be delivered. The results presented here will be useful for the seismic rehabilitation of the historical buildings composed of aggregates. Engineers in common design practice will be able to model the interactions between units following this approach that uses the EFM, a low time consuming and computational effort numerical method, in the design of strengthening interventions of complex masonry aggregates.