A Simplified Approach to Estimate Seismic Vulnerability and Damage Scenarios Including Site Effects. Application to the Historical Centre of Horta, Azores, Portugal

The research attempts to provide a method for evaluating the susceptibility of heritage buildings and potential damage considering local site effects, using as a case study an urban sector situated in Horta, Faial, Azores, Portugal. The physical vulnerability of the investigated structures was appraised using an index-based method devised for structural masonry aggregates to emphasize their likelihood of seismic damage. As a result, a damage scenario based on real accelerograms collected after the 1998 Azores seismic event was developed by using a reliable seismic intensity prediction equation. In addition, the soil amplification, which increases the extent of seismic damage to the examined structures, is assessed by varying the soil conditions using EN 1998–1 Code. Thus, this research emphasises the ground impact in forecasting the expected damage scenarios, enabling optimised risk mitigation strategies in urban settings.