Immediate Decision Support on Re-occupancy of Earthquake-Affected Buildings Based on Assessment of Aftershock Risk

Abstract

After a huge earthquake, buildings subjected to strong ground shaking may suffer damage that possibly classifies them to be unsafe for occupancy. Knowing the aftershock risk can support post-earthquake decision-making on the re-occupancy of earthquake-affected buildings. The aftershock risk of buildings with defined damage levels is evaluated stochastically based on fragility curve and aftershock hazard analysis. After the mainshock, the damage level of the building is estimated from structural health monitoring. The combination of the pre-computed aftershock risk and post-event damage estimates yields the re-occupancy index for the damaged buildings. As an example study, this method is applied to the low rise steel frame building against the assumed Nankai megathrust earthquake.