Vulnerability assessment of building aggregates: a macroseismic approach

Abstract

The evolution of the urban layout is of great importance in the seismic behaviour of buildings in urban areas. The chronological construction process frequently results in characteristic heterogeneity of masonry wall fabric and connection quality. In addition, buildings do not constitute independent units given that they share the midwalls with adjacent buildings and the façade walls are aligned. Thus, as post-seismic observations proved, buildings do not have an independent structural behaviour, but they interact amongst themselves, mainly for horizontal actions and so the structural performance should be evaluated at the level of the aggregate and not only for each isolated building. In most cases, for masonry structures there is no need for sophisticated dynamic analyses to assess seismic vulnerability taking to account all the inherent uncertainty of such analysis. This is even more relevant when an assessment at the level of a city centre is pursued. In this paper, attention will be focused on the exposure of the simplified method based on the concept of the evaluation of building parameters that compose an aggregate, such as geometrical irregularities, building typology differences and interaction issues. This method was applied to an old city centre and results are treated and shown resourcing to a GIS application.