Seismic behaviour of a mixed iron-masonry church: Santa Maria Maddalena, Ischia

Abstract

The concept of vulnerability of the existing building stock is receiving increasing awareness and central importance in the scientific community working in earthquake risk mitigation. This assumes even more relevance when dealing with heritage structures located in relevant seismic hazard zones. This paper aims to identify and describe the earthquake-resistant features found in a unique masonry church in Ischia (Italy), and discuss their effectiveness on the impact of the post-seismic damage through the application of non-linear static analyses. The Santa Maria Maddalena Church represents one of the rare examples in which the technology of the Borbonic casa Baraccata (mixed timber-masonry construction), already well-known in the literature for its use in Italian seismic areas since the eighteenth century, is applied with the non-conventional combination of masonry and iron frames. The church was struck by the recent earthquake of 21 August 2017 with epicentre in Casamicciola Terme. The recorded post-seismic damage of the church evidenced non-relevant structural crack patterns, which are likely to be related to the efficacy of the construction system adopted.