Drift-based fragility functions for hollow clay masonry infills in RC buildings under in-plane seismic actions

Reinforced Concrete (RC) framed buildings with clay masonry infills are a very common structural typology worldwide for civil, strategic or productive use. Nevertheless damage to infills may cause danger for human lives and strongly affected economic losses due to past earthquakes, in current practice, infills are considered as partition elements without any structural function. However, their role is crucial in terms of global and local response of RC buildings in the event of earthquake, and, therefore, their behaviour under seismic actions should be reliably characterized, starting from the analysis of their displacement capacity at different performance levels due to in-plane actions. In this paper, a homogenous extensive database of experimental tests on clay-masonry infilled RC frames is collected and presented. Displacement capacity at given performance levels are identified and correlated to the in-plane behaviour of the infill panels. The analysis of the damage evolution to the infills during the experimental tests finally allows the definition of fragility functions for these non-structural components, representing a key point for a reliable estimation of losses due to earthquakes.