Issue 51

C. Ferrero et alii, Frattura ed Integrità Strutturale, 51 (2020) 92-114; DOI: 10.3221/IGF-ESIS.51.08

a) b) Figure 18: Correlation between the real and numerical damage occurred in the north wall of body B due to the August 24 th earthquake (PGAx = 0.33 g): a) cracks observed in-situ [11, 12], b) crack pattern in terms of principal crack width for a horizontal load of 0.33 g in the -X direction.

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c) d) Figure 19: Correlation between the real and numerical damage occurred in the north external walls of body A due to the October 26 th earthquake (PGAx = 0.36 g): a-b) cracks observed in-situ [11, 12], b-d) crack pattern in terms of principal crack width for a horizontal load of 0.37 g in -X direction. With respect to the pushover analyses performed in the direction of the Y global axis, a moderate damage is obtained under the lateral load of 0.32 g, representing the PGA of the August 24 th earthquake, in both the positive and negative directions. Differently from what observed for the X direction, the severity of the damage increases significantly under horizontal loads comparable to the PGA registered in the Y direction of the building in the October 26 th earthquake (Figure 17). This was expected since the PGA of the October 26 th earthquake was 1.5 times higher than the one of the August 24 th earthquake (0.32 g). Furthermore, from Figure 15 it can be observed that the structure has just exited the linear elastic range for the PGA of the August 24 th earthquake, whereas it shows a highly nonlinear response for the October 26 th earthquake. Under a lateral load of 0.32 g (August 24 th ) an average top displacement of about 12 mm is obtained in both +Y and -Y direction, whereas the top displacement increases to about 37 mm and 42 mm in the +Y and -Y directions, respectively, for horizontal

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