MARQUES, A. I.1; CANDEIAS, P. X.2; VEIGA, M. R. 3; FERREIRA, J. G. 4

1) MSc, LNEC, DED/NRI, aimarques@lnec.pt

2) PhD, LNEC, DE/NESDE, pcandeias@lnec.pt

3) PhD, LNEC, DED/NRI, rveiga@lnec.pt

4) PhD, IST, DECivil, joao.gomes.ferreira@ist.utl.pt

The seismic vulnerability of old buildings is of particular concern in regions of moderate to high seismic hazard like Portugal.

An ongoing study is focusing on a Portuguese building typology built between 1920 and 1940, characterized by the combination of reinforced concrete slabs and resistant masonry walls. The seismic performance of this type of buildings is deemed weak due to poor mechanical properties in terms of strength and ductility of the masonry walls, deficient interconnections between perpendicular walls and between walls and floors and lack of integrity of the whole building.

In this paper a literature survey of reinforcement techniques best suited for this type of buildings is presented and discussed. Some issues will be addressed, namely the effectiveness of the techniques for the in plane resistance of the walls and the interconnection between perpendicular walls to prevent out of plane collapse. However, considering the historic character of the referred typology, other issues will also be taken into account, such as material compatibility, durability and reversibility, while trying to preserve the authenticity of the architectural heritage.

The effectiveness of using reinforced renders as a reinforcement technique will be particularly discussed, in the context of using sustainable and compatible materials.

Keywords: retrofitting techniques, masonry shear walls, seismic vulnerability, reinforced renders