Considering uncertainty in the collapse fragility of New Zealand buildings for risk‐targeted seismic design

The risk-targeted seismic design framework is used to set intensities, based on achieving a target risk level (e.g., collapse or fatality risk) with respect an assumed building response. This paper assesses the distribution of associated intensity, considering uncertainty in both hazard and variety buildings that can satisfy minimum requirement. randomness among their response due other decisions (aleatory variability intensity) be represented by fragility curves quantify probabilities as-built, code-conforming buildings. First, single intensity calculated “design fragility,” mean curve, target. taken as conservative estimate from fragilities selected approximates New Zealand's previous (non-risk-targeted) criteria for intensities. Then assessed, aleatory as-built epistemic new National Seismic Hazard Model. Accounting model produces more fully represents potential given intensity. compared guidance tolerable ranges, which suggest variable but should fall within acceptable bounds. Sensitivity studies consider fragilities. inclusion assess offers powerful extension framework. While this would not affect engineering practice (as output still intensity), it allows code developers better understand implications