OUT-OF-PLANE TESTING OF MASONRY INFILL WALLS MADE WITH LIGHTWEIGHT CONCRETE BLOCKS 0 $JDQWH $  $ )XUWDGR %  + 5RGULJXHV   $ $UrGH &  3 )HUQDQGHV   + 9DUXP '  &216758&7/(6( )DFXOGDGH GH (QJHQKDULD GD 8QLYHUVLGDGH GR 3RUWR 3RUWR 3RUWXJDO HPDLO $ ｱ XS#HGXIHXSSW %  DIXUWDGR#IHXSSW &  DDUHGH#IHXSSW DQG '  KYDUXP#IHXSSW  5,6&2 8QLYHUVLGDGH GH $YHLUR $YHLUR 3RUWXJDO KURGULJXHV#XDSW  ,QVWLWXWR 3ROLWpFQLFR GH /HLULD /HLULD 3RUWXJDO SDXORIHUQDQGHV#LSOHLULDSW Abstract The masonry infill walls are widely spread over the reinforced concrete buildings due to dif- ferent demands. The buildings' thermal energy efficiency is a top priority nowadays since many of the existing building stock comprises buildings with low energy performance. The buildings' external envelope is suffering a transformation with the appearance of the vertical hollow concrete blocks with high thermal and acoustic demands. However, recent evidence from a strong earthquake shows that the masonry infill walls are vulnerable to out-of-plane loadings and were responsible for many casualties, injuries, and economic losses. Based on that, this work's main objective is to study the out-of-plane (OOP) behaviour of masonry in- fills made with vertical hollow concrete blocks. The experimental campaign comprises the OOP testing of three full-scale infill walls made up of these masonry units. One of them was as-built without previous damage, one with previous damage due to an earlier in-plane test and the third one retrofitted. All the tests consisted of applying the loading-unloading- reloading history of imposed displacements in the OOP direction through a uniformly distrib- uted load. The results will be presented in terms of OOP force-displacement responses, de- formed shapes, damage evolution, energy dissipation capacity and damping. Finally, the test results are compared to each other to assess the previous damage and the retrofit technique's effectiveness. Keywords: 0DVRQU\ LQILOO ZDOOV 2XWRISODQH EHKDYLRXU OLJKWZHLJKW FRQFUHWH EORFNV ([SHU LPHQWDO WHVWLQJ 1212 COMPDYN 2021 8 th ECCOMAS Thematic Conference on Computational Methods in Structural Dynamics and Earthquake Engineering M. Papadrakakis, M. Fragiadakis (eds.) Streamed from Athens, Greece, 28 - 30 June 2021 Available online at www.eccomasproceedia.org Eccomas Proceedia COMPDYN (2021) 1212-1222 ISSN:2623-3347 © 2021 The Authors. Published by Eccomas Proceedia. Peer-review under responsibility of the organizing committee of COMPDYN 2021. doi:10.7712/120121.8557.19187