PSI - Issue 44

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Alessandro Lubrano Lobianco et al. / Procedia Structural Integrity 44 (2023) 910–917 A. Lubrano Lobianco et al./ Structural Integrity Procedia 00 (2022) 000 – 000

915

Table 2 - Global averaged and peak damage level (DL) for analysis with 150% of intensity of earthquake

1.00 X

1.00 Z

1.00 X + 0.30 Z

0.30 X + 1.00 Z

DS

average

peak

average

peak

average

peak

average

peak

1 2 3

X

X

X

X

X

X

X

X

4.2 Intensity of the ground shaking Results are reported in Table 3 for a fixed loading scenario (1.00X) under ground shaking of increasing intensity. The peak and average DL global are reported, along with the variation of vibration period experienced by the building along the X direction after the ground shaking. It can be observed that the average DL global is usually lower than the peak one. For the considered loading scenario, the building reaches a DL4 for an IDR max of 3.92% and with a period elongation of 41.9% with respect to the undamaged configuration. For the loading scenario 1.00X+0.30Z the IDR max and the elongation of period in the X direction show no significant differences with respect to the 1.00X scenario. However, the bidirectional loading affects significantly the mode of vibration of the building in the Z direction.

Table 3 - Summary of global damage level and correlated period variation for the first loading scenario (1.00 X)

Intensity of earthquake (%)

IDR max (%)

DL peak (-)

DL average (-)

Period variation – Loading direction (%)

Scenario

10 20 40 60 80

0.29 0.55 1.18 1.84 2.63 2.23 1.91 2.19 3.92

DL0 DL1 DL1 DL2 DL3 DL3 DL3 DL3 DL4

0.00 0.33 0.33 0.67 1.00 1.44 2.00 2.33 2.33

DL0 DL0 DL0 DL1 DL1 DL1 DL2 DL2 DL2

+2.2

+13.4 +17.5 +20.0 +36.9 +32.4 +35.4 +39.0 +41.9

1.00 X

100 125 150 200

4.3 Summary of results Data obtained from all the considered loading scenarios and all the chosen earthquake intensities are then analyzed to derive ranges of variation of the period elongation of the building as a function of the global damage level experienced. Results are summarized in Table 4 both for peak and average global damage level. Results in terms of period elongation, ΔT, are also plotted in Fig. 4 and compared with the ranges of variation derived in (Lubrano Lobianco et al., 2021)) for RC columns. In detail, colored markers represent the period elongation of the case-study building while black plots represent the ranges of variation of vibration period for the columns. It can be noted that for each loading condition (1.00 X, 1.00 Z, 0, 3 X + 1.00 Z, 1.00 X + 0.3 Z) and for each intensity of AQG earthquake the markers fall within the range estimated in the previous study for the RC column, if the DL corresponding to the peak IDR is considered. On the other hand, considering the weighted average value of μ d