The fragilities for the unrepaired and repaired bridge largely deviate from each other under the extensive and collapse damage states.
Similarly, the results under severe MS-moderate AS sequences from ensemble 1 and 2 for minor, moderate, extensive and collapse damage states are presented in Fig. 14a h, respectively.
Under extensive and collapse damages states far-fault aftershocks appeared more significant compared to near-fault aftershocks for severe MS-severe AS sequence.
The drift limits considered for the bridge columns were 0.005, 0.007, 0.015, 0.025 and 0.05 for no damage, minor, moderate, extensive and collapse damage states, respectively.
Thermo-induced damage affects the structural and material safety of civil engineering structures; the damage can induce direct or indirect extensive structural collapse.
Four damage states, namely minor, moderate, extensive and collapse as defined by HAZUS-MH (2003) were adopted herein, in which they were correlated with the quantitative engineering demand parameters.
On the contrary, in the three story frame, the median of near-field is lower than the far-field, especially in extensive and collapse damage state, implying higher vulnerability of three story frame in near-field.
Fragility curves for two intensities of MS-AS, namely severe MS-severe AS and severe MS-moderate AS are developed for four damage states, namely slight, moderate, extensive and collapse.
The fragility curves for the studied bridge in the repaired and unrepaired condition under severe MS-severe AS set of records from ensemble 1 (far-fault) and ensemble 2 (near-fault) for minor, moderate, extensive and collapse damage states are presented in Fig. 13a h, respectively (Fig. 13a d for ensemble 1 and Fig. 13e h for ensemble 2).
While Fig. 13a, e (similarly, Fig. 14a, e) clearly indicate that the fragility curves for the unrepaired bridge almost overlaps the repaired bridge under the minor damage state, the unrepaired bridge's vulnerability is significantly larger than the repaired bridge for the extensive and collapse damage states (Figs. 13c, d, g, h, 14c, d, g, h).
