Seismic vulnerability assessment and characterisation of the buildings on Faial Island, Azores

Abstract

The earthquake of the 9th of July 1998 that hit in the central group of the Azores archipelago greatly affected the islands of Faial, Pico and São Jorge, reaching a magnitude of Mw 6.2 with the epicentre located about 15 km northeast of the Faial Island. This earthquake allowed the collection of an unprecedented quantity of data concerning the characterisation of the building stock and the damage suffered by construction. This is the main purpose of this research, consisting essentially of three main aspects: (i) A detailed characterisation of the building stock, assigning a five category classification, from old traditional rubble stone masonry to reinforced concrete moment framed buildings; (ii) A detailed damage grade classification based on the different damage mechanisms observed; and, (iii) A seismic vulnerability assessment of the building stock. The results of the vulnerability assessment together with the building stock database and damage classification were integrated into a GIS tool, allowing the spatial visualation of damage scenarios, which is potentially useful for the planning of emergency response strategies and retrofitting priorities to mitigate and manage seismic risk.

Out-of-plane behaviour of existing stone masonry buildings: experimental evaluation

“…The first aspect is normally associated with large panels, typically façades or panels at floor levels or in between floors, among others as reported in existing studies (D'Ayala and Speranza 2000;Neves et al 2007Neves et al , 2011. The second issue is related with the local collapse of walls, that can also lead (or not) to the partial or total collapse of the structure, which mainly depends on the structural typology and its redistribution capacity.…”

Seismic Vulnerability Assessment of Slender Masonry Structures

“…This connection is made using wedges (timber peg) that fix the wall plate along the perimeter through the joists that run inside and outside the building, as shown in Figure 3.7. The wall plate, which runs throughout the perimeter of the wall constituting a type of ring-beam, allows a better distribution of the dead and live loads along the wall length, also allowing a better in plane stiffness and stress distribution [112]. The floor is then joined to the horizontal frame (wall plate) using battens, some of which also run through the wall and are fixed in position using wooden wedges.…”

Seismic vulnerability of vernacular buildings in urban centres—the case of Vila Real de Santo António

“…This index can be used to estimate structural damage after correlation to a specified seismic intensity, supported by post-earthquake recordings and statistical studies. They constitute a reliable large-scale assessment and have been extensively applied in Italy (GNDT 1994), and were recently implemented for the seismic vulnerability assessment of Portuguese masonry structures in several historical city centres (Vicente et al 2011;Neves et al 2012;Ferreira et al 2013), obtaining useful and reliable results, as a first level approach.…”