Computation of the repairability index of short buildings with rocking connections

Recently developed steel self-centring moment-resisting frames have been analytically and experimentally validated as having the potential to eliminate structural damage under a design basis earthquake and restore their original vertical position following a major earthquake. In this study, the repairability index of post-tensioned self-centring frame for near-field earthquake has been developed. According to the six models of the studied building, a building that can be repaired, the maximum rotation in its connection after the earthquake does not exceed the rotation of the immediate occupancy performance. Based on this, the output data of incremental dynamic analysis analyses were drawn according to the connection of relative rotation and spectral acceleration. According to the predicted performance levels for each acceleration level, the value of the connection opening is divided by the opening of the design-basis earthquake level. The resulting curve shows the repairability index according to spectral acceleration, which if less than one, the repairability target is achieved. To evaluate the damage, the angle failure probability of post-tensioned self-centring frame for near-field earthquake has been developed. This index equation is determined according to the fragility curve and the intensity of damage in each building.