# Out-of-Plane Experimental Study of Strengthening Slender Non-Structural Masonry Walls
## 2 Experimental Program
### Strengthening Systems  
Eight out of eleven prepared wall specimens were strengthened using four strengthening methods (strengthening systems A, B, C, and D) with different geometry patterns, as shown in Figure 2. A glass fiber-reinforcing fabric (RF) with a density equal to 286 g/m\({}^{2}\) or a glass fiber-rendering mesh (RM) with a density equal to 145 g/m\({}^{2}\) was applied as the reinforcing material, either on the entire plane surface of the wall specimens or locally with reinforcement strips. The glass fiber-reinforcing fabric is part of a commercially available system for reinforcing masonry partition walls, whereas the glass fiber-rendering mesh is ordinarily used for reinforcement of thin coat facade plaster. The tensile strength of RF and RM is equal to 92 kN/m and 34 kN/m, respectively. The RF is a bidirectional textile with a maximum elongation at rupture equal to 4%, while the RM is a bidirectional mesh with a square size equal to 4 mm x 4 mm and has a maximum elongation at failure equal to 2%. Nevertheless, the RM appears to be more economical, with its price being up to 20 times lower in comparison to the RF.  
Both strengthening materials were applied to cleaned and leveled surfaces of the wall through the use of one-component, ready-to-use flexible polyurethane-based adhesive in watery dispersion. In the first two methods, a glass fiber-reinforcing fabric (strengthening system A) or a glass fiber-rendering mesh (strengthening system B) was applied to both sides of the wall over the entire wall surface. The glass fiber fabric or rendering mesh ran continuously from the lower to the upper edge of the test specimen with 10 cm of excess fabric anchored at the top and bottom edge of the wall. The third strengthening method (strengthening system C) was performed locally with strips of glass fiber-reinforcing fabric, using two wide diagonal strips as tension reinforcements combined with horizontal reinforcement strips at the levels of load application. In the fourth strengthening method (strengthening system D), the geometry of local reinforcement strips was the same as in system C, but strips of glass fiber-rendering mesh were used instead of reinforcing fabric. The width of the diagonal and horizontal reinforcement strips was 20 cm. All strengthening systems were applied on both sides of the specimens. Systems A and B were implemented on three specimens, whereas methods C and D were implemented on a single specimen. In further discussion within the present paper, the following labels will be used: NF-1A, NF-2A, and NF-3A for specimens with applied strengthening system A, labels NF-1B, NF-2B, and NF-3B for specimens with strengthening system B, NF-1C for specimen with strengthening system C, and NF-1D for specimen with strengthening system D. All details about specimens' labels, symbols, and applied strengthening systems are summarized in Table 1.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Specimen’s** & **Specimens’** & **Strengthening** & **Strengthening System Details** & **Symbol** \\
**Label** & **Group Label** & **System Label** & **Strengthening System Details** & **Symbol** \\ \hline NF-1 & & & & As-built \\ NF-2 & NF & & & (without strengthening system) \\ \hline NF-1A & & & & \\ NF-2A & NF-A & A & Glass fiber-reinforcing fabric (RF) applied to both sides & \\ NF-3A & & & of the specimen over the entire surface & \\ \hline NF-1B & & & & \\ NF-2B & NF-B & B & Glass fiber-rendering mesh (RM) applied to both sides & \\ NF-3B & & & of the specimen over the entire surface & \\ \hline NF-1C & NF-C & C & Glass fiber-reinforcing fabric (RF) diagonal strips & \\  & & & combined with horizontal strips applied to the both sides of the specimen & \\ \hline NF-1D & NF-D & D & Glass fiber-rendering mesh (RM) diagonal strips & \\  & & & combined with horizontal strips applied to the both sides of the specimen & \\ \hline \hline \end{tabular}
\end{table}
Table 1: Matrix of specimens and applied strengthening systems.  
Figure 2: Geometry of applied strengthening systems.