Seismic Meta‐Fragility Functions

ABSTRACT Fragility functions make for one of the three key components of probabilistic seismic risk analysis, along with hazard and consequence and/or exposure models. They are, in principle, construction‐specific; however, risk analysis is more often performed on a larger (e.g., regional) scale. In this case, so‐called typological fragility curves are intended to be applied to populations (i.e., classes) of structures, rather than to any of its members specifically. When these curves are obtained via mechanical/numerical approaches, they are typically based on numerical models, intended to be representative of the class of interest. In the short communication, an approach that reconciles class‐scale and structure‐specific vulnerability in the derivation of fragility functions is discussed. It materializes into a hierarchical model degenerating in a fragility function conditionally to the construction‐specific information, yet it can be used for large scale risk assessment when such information is uncertain. To derive the meta‐fragility, among other options, the response‐surface approach is discussed. In the way it is postulated, such modeling approach can be used also to derive fragility from earthquake damage observations.