A new global vulnerability model for regional seismic risk assessments: Part 1 – structural vulnerability

Abstract Reliable vulnerability functions are essential for earthquake risk assessment, yet those currently used in regional and large-scale contexts often rely on numerical models that oversimplify the complex behaviour of buildings. This can lead to biased predictions of structural performance and earthquake-induced losses. In the new Global Vulnerability Model supported by the Global Earthquake Model (GEM) Foundation, we present an improved structural vulnerability database for seismic risk assessment, featuring four key advances: 1) the number of building classes has been expanded from approximately 500 classes to over 1,400 to consider additional structural systems and seismic code levels; 2) an improved numerical modelling strategy that simulates the seismic response using efficient multi-degree-of-freedom stick-and-mass models; 3) an extensive dataset of ground motion records for response analysis covering diverse tectonic settings (e.g., active shallow crust, stable continental, and subduction zones), and 4) a new suite of vulnerability functions addressing specifically structural damage. This contribution describes the vulnerability modelling for structural components, which is used to compute damage and monetary losses within the scope of GEM’s Global Seismic Risk Model. The derived vulnerability functions in this study are available in an open-access repository for use in both probabilistic and scenario-based seismic risk assessments.