Building Performance Loss After Damaging Earthquakes: an Investigation Towards Reparability Decisions

In the aftermath of damaging events, agreed and transparent policies should establish acceptable levels of safety, and facilitate decisions on appropriate course of action for specific buildings. A significant indicator for repair and/or upgrade decisions is the Performance Loss (PL), that is a measure of variation of building seismic capacity from intact to damaged state. However, it is not clear how to choose significant PL thresholds with regard to damage acceptability. This study investigates, by means of a detailed case study, the expected PL for increasing seismic demand and its relationship with varied building safety level. The response of an existing non-ductile reinforced concrete building is simulated using a finite element model that properly accounts for both flexural, shear and axial failure of members and simulates joints behavior. Different definitions of building collapse are introduced, and consistent assessment of building PL are performed. The study shows interesting relations between PL and building safety level for varying return period of the damaging earthquake, demonstrating its usability as a practical indicator for reparability.