Issue 57

A. Sadeghi et alii, Frattura ed Integrità Strutturale, 57 (2021) 138-159; DOI: 10.3221/IGF-ESIS.57.12

Figure 15: Comparison of the failure probability of frame for different LSFs .

Fragility Analysis In current paper, fragility analysis is an available gadget for assessing the performance of structures under vehicle impact loading scenario. Fragility curves can be performed using the developed framework in this study by two approaches including an exact method and Kriging surrogate model. In these methods, the fragility analysis is conducted for evaluating the behavior of a prototype SMRF through different damage levels. Based on Eqn. 18, the parameters such as the fragility function F d (x) , damage measure ( DM ), and the intensity measure ( IM ) are mentioned.

Fd (x) = P (DM ⩾ d|IM = x)

(18)

Therefore, the damage measure is defined by the maximum beam rotation in the damaged bay. In the following, fragility curves have been completely described as a function of gravity loads for progressive collapse assessment [57]. Also, the intensity measure in the above mentioned equation is considered as the vehicle velocity.

a)

b)

Figure 16: Fragility curves for vehicle impact scenario by two methods: a) Exact method by OpenSees software; b) Kriging meta - model.

The fragility curves are plotted by two approaches such as an exact method by OpenSees software outputs and Kriging meta - model under vehicle impact loadings. Based on Fig. 16 (a) and (b), it is seen that the SMRF structure is more vulnerable to vehicle collision by two methods and its fragility curves showed that by increasing the vehicle velocity, the performance of the studied frame is changed critically. The median collapse velocities associated with the light, moderate, and severe damage

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