## 4 Results of Numerical Analysis
### Full-Scale Walls  
As for wall parts in the models of full-scale walls, the results of the numerical analysis were compatible with the experimental results regarding both the load-carrying capacity and the way they are damaged. The image of damaged parts of the walls obtained with the non-contact optical system during the laboratory tests and the numerical model at the failure phase are compared in Figure 20.  
Results of the numerical analysis were compared with mean values of destructive force and deflection obtained for each series of the tested models. For the model MNSO, the maximum destructive force acting on the lintel was 210 kN, and the deflection was 11.7 mm. The obtained destructive force was greater by 9% than the force obtained during the tests, and the value of deflection constituted 36% of the experimentally obtained deflection. For the numerical model MSO, the obtained destructive force of 215 kN was equal to the test force, and the deflection of 24.1 mm was greater by 84% than the corresponding deflection obtained during the laboratory tests. Similar discrepancies between the results from the numerical analysis and laboratory tests were observed for the model M2 SO. The destructive force of 255 kN was smaller by 4%, and the deflection of 23.4 mm was greater by 200% than the corresponding destructive force and deflection obtained during the laboratory tests. Figure 21  
Figure 20: Comparison of damage recorded by the optical system and the deformation in the numerical model of the walls of series: (**a**) MNSO, (**b**) MSO, (**c**) M2 SO. presents the relationship between the load and the displacement of the numerical models and the tests models of confined walls. A few operating phases of the Intel/masonry/reinforced concrete elements could be distinguished in all tested models of walls. The elastic phase in the test and numerical models began from the moment of loading until the formation of the first cracks in the Intel induced by its deflection or a crack in the bed joint over the Intel (crack opening in the interface elements in the numerical model). Then, there was a post-elastic phase lasting from the moment of the Intel cracking (crack opening in the interface elements) to the moment of reaching the destructive force. After reaching the value  
Figure 21: Compared relationship between the load and the displacement of the Intel, determined experimentally and from numerical calculations for the models of the following series: (**a**) MNSO, (**b**) MSO, (**c**) M2 SO. of the ultimate force Fu, the model entered into the softening phase, during which a further increase in the lintel deflection occurred and was disproportional to the change in the loading force exerted on the research model. In that phase, cracks were significantly wider. Moreover, spalling of masonry units and loosening of the concrete cover were observed. The softening phase in the numerical model was not apparent, despite using the contact elements and the elastic-plastic model of the material. Further development of the applied model is required to include that phase in the numerical calculations. However, it is a difficult task, as the models behaved differently in the final phase after reaching the destructive force value. In the models with inner peripheral confinement (M2 SO series), there was a rapid decrease in the load, whereas vertical displacements of the intels were greater. In the non-confined MNOS models and the MSO models confined along their perimeter, the softening phase was mild. The destructive force obtained for non-confined walls was kept constant while deflection of the lintel was increasing. For the most confined walls (M2 SO models), when the ultimate force was reached, there was an increase in deflection of the lintel and a simultaneous slight increase of the load. The sequence of damage was similar in laboratory tests and numerical analyses. In the non-confined walls of the MNSO series, cracking was at first noticed in the lintel over supports at a deflection of ca. 0.8 mm obtained during the tests.