## 3 Materials and Methods
### Pull-Out Tests  
The metal anchors used for the pull-out tests in the present study were supplied by HILTI. The anchors had 10 mm diameter and different lengths according to the type of anchoring system, namely, mechanical or adhesive (chemical and grout). The technical specifications in terms of length (\(l\)) and effective embedment (\(h_{ef}\)) are presented in Table 4, as provided by the manufacturer. For the application of the anchors (including drilling for  
Figure 4: Geometry of the walls for pull-out tests (dimensions in cm).  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Compressive Strength** & **Compressive Strength** & **Tensile Strength** & **Shear Strength** \\
**(A) (MPa)** & **(B) (MPa)** & **(MPa)** & **(MPa)** \\ \hline
9.84 (2.63) & 8.82 (7.91) & 0.10 (12.82) & 0.21 (12.81) \\ \hline \hline \end{tabular}
\end{table}
Table 3: Mechanical characterization of the masonry walls (CoV between parenthesis).  
adhesive fasteners) as well as for the pull-out tests, a compressive stress of 0.2 MPa was applied on top of the walls in order to reproduce the confinement effect induced by the vertical loads in a real facade.  
The resin used for chemical anchoring was injected using specific equipment provided by HILTI (HDE 500-A22 battery-operated dispenser), whereas the cementitious grout (Mapefill P from MAPEI) was injected manually using a syringe. For both cases, holes 20 mm in diameter (twice the dimension of the fastener) were drilled into the walls. A schematic description of the system used for the cementitious grout anchor is shown in Figure 5. In particular, a screw nut was welded at the end of the anchor to ensure a centered fit within the drill hole and allow the placement of the injection and air outlet tubes.  
The pull-out tests were performed after the application of the mechanical anchors and after the curing period in the case of adhesive anchors. The setup employed for the pull-out tests is shown in Figure 6. During the tests, a compressive stress of 0.2 MPa was applied on top of the walls, as previously mentioned. Moreover, the walls were fixed to the testing frame to prevent their displacement. A hinged joint was used to connect the head of the anchor to the actuator. Linear variable differential transformers (LVDTs) were used to measure displacements in the areas outside and inside the expected cone failure induced by the pulling force.  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multicolumn{2}{c}{**Mechanical Anchor**} & \multicolumn{3}{c}{**Chemical Anchor**} & \multicolumn{3}{c}{**Cemetitious Grout Anchor**} \\ \hline
**Type** & \(I\) **(mm)** & _h\({}_{\textit{ef}}\)_**(mm)** & **Type** & \(I\) **(mm)** & _h\({}_{\textit{ef}}\)_**(mm)** & **Type** & \(I\) **(mm)** & _h\({}_{\textit{ef}}\)_**(mm)** \\ \hline \multirow{3}{*}{
\begin{tabular}{c} HUS3-H 10 \\ screw anchor \\ \end{tabular} } & \multirow{3}{*}{100} & \multirow{3}{*}{85} & Resin HIT-RE & \multirow{3}{*}{190} & Mapefill P Grout; & \multirow{3}{*}{190} & Mapefill P Grout; & \multirow{3}{*}{190} & \multirow{3}{*}{150} \\  & & & & M10 & & HIT-V-8.8 M10 & & HIT-V-8.8 M10 & \\ \cline{1-1} \cline{5-7}  & & anchor rod & & & anchor rod & & \\ \hline \hline \end{tabular}
\end{table}
Table 4: Specifications of the anchoring systems applied on the masonry walls.  
Figure 5: System used for the cementitious grout anchor. Adapted from [16].