FURTADO, A.1; RODRIGUES, H.2,3; VARUM, H.3,A;COSTA, ANÍBAL3,B

1Departamento de Engenharia Civil, Faculdade de Engenharia, Universidade do Porto, afurtado@fe.up.pt

2Departamento de Engenharia Civil – ESTG – Instituto Politécnico de Leiria, hugo.f.rodrigues@ipleiria.pt

3Departamento de Engenharia Civil, Universidade de Aveiro, Ahvarum@ua.pt, Bagc@ua.pt

The assessment of seismic vulnerability and strengthening of existing buildings is a topic of relevant importance and priority, as evidenced in recent earthquakes around the World, particularly in Southern European countries. Some architectural solutions adopted in the 1970s, combined with the common design and construction practices at that time, particularly in what regards the seismic design, influences the seismic vulnerability of these structures.

The objective of the present work is to study, based on numerical analyses, possible solutions to strengthen existing reinforced concrete buildings, particularly buildings with the behaviour potentially governed by soft-storey mechanisms. A reinforced concrete building, representative of existing buildings in Southern European countries will be studied. The seismic safety of the building will be assessed considering the influence of masonry infill panels in the upper storeys, but not in the ground floor, in terms of the seismic response of the buildings is analysed.

Also, different strengthening techniques will be tested to fix/eliminate the soft-storey like response, namely: RC column jacketing, addition of RC shear walls, addition of steel bracings with and without shear link .The strengthened buildings will be compared with the results for the original structure, deducting about the structural performance improvement by each type of strengthening technique studied.

Keywords: RC buildings, infill masonry, soft-storey mechanism, seismic vulnerability, retrofit strategies