Experimental study of the out-of-plane behaviour of two-leaf brick masonry walls in different condition: Unstrengthened, strengthened and repaired

This study investigates the out-of-plane behavior of two-leaf brick masonry walls under seismic-like loading through an experimental campaign involving three U-shaped wall specimens: an unstrengthened wall (UMW), a repaired wall (RMW) using Textile Reinforced Mortar (TRM), and a newly built, pre-strengthened wall (RMW_UND). Using airbag quasi-static loading and non-destructive testing methods (e.g., sonic testing), the structural response, damage patterns, and energy dissipation of each configuration were evaluated. Results show that TRM significantly enhances out-of-plane strength, ductility, and energy dissipation capacity. RMW_UND displayed a 93 % increase in lateral capacity compared to UMW, while RMW, despite its damaged conditions, achieved improvement of its performance. These findings validate the TRM solution selected as an effective option for both preventive strengthening and post-damage repair of existing masonry, particularly in seismic-prone regions. • Overview of experimental works for the assessment of the out-of-plane performance in masonry walls. • Mechanical parameters estimation via non-destructive testing procedure. • Analysis of the experimental cyclic response of 2-leaf brick masonry walls in damaged and undamaged conditions. • Analysis of the efficiency of a TRM strengthening solution in improving the out-of-plane performance of damaged and undamaged 2-leaf brick masonry walls.