OpenQuake Engine: An Open Hazard (and Risk) Software for the Global Earthquake Model

Abstract

Since its inception in the 1960s, probabilistic seismic‐hazard analysis (PSHA) (Cornell, 1968; McGuire, 2004, 2008) has emerged as the principal methodology for assessing the potential hazard posed by earthquake ground motion in a broad range of contexts. Seismic‐hazard analysis serves different needs coming from a wide spectrum of users and applications. These may encompass engineering design, assessment of earthquake risk to portfolios of assets within the insurance and reinsurance sectors, engineering seismological research, and effective mitigation via public policy in the form of urban zoning and building design code formulation. End users of seismic‐hazard analyses from different sectors of industry may often have specific requirements in terms of the types of results and, as a consequence, in terms of the methodologies preferred for calculation. A large majority of studies for the analysis of structural and geotechnical systems require the calculation of a target response spectrum derived from PSHA results (e.g., Lin et al. , 2013). Often the calculation of uniform hazard spectra is performed in conjunction with a disaggregation analysis, which in the simplest cases highlights the combinations of magnitude and distances, providing the largest contributions to a specific level of hazard for a particular intensity measure type, such as the spectral acceleration for a period close to the fundamental elastic period of a structure (Bazzurro and Cornell, 1999; Pagani and Marcellini, 2007). In contrast, in the insurance sector it is more common to use stochastic methodologies (e.g., Weatherill and Burton, 2010; Musson, 2012) to produce multiple realizations of the likely earthquake activity that may be pertinent to a portfolio of assets. Monte Carlo–based methods can provide results in a form that offers a practical comparison with past events and can better account for the temporal and spatial variability of earthquake shaking occurring on a distributed set …