Displacement-based fragility functions for New Zealand buildings subject to ground motion hazard

Building fragility functions provide a probabilistic representation of a building damage potential due to a hazard of a varying intensity. A simplified probabilistic displacement-based framework is adopted to develop fragility functions for NZ building inventory subject to ground motion hazard. To account for the diversity of building characteristics within a given building class, a Monte-Carlo procedure is adopted to simulate geometrical and material property variables of buildings. The adopted displacement-based approach uses mechanically derived formulae to describe displacement capacities of classes of buildings for four different damage states. A practical and simplified approach is suggested to consider the uncertainty associated with spectral displacement demands. The probability of damage state failure is then determined by comparing the spectral displacement demand with spectral displacement capacity computed from building characteristics