Ground Motion Analysis Toolbox and Seismic Scenarios Toolbox: software tools for seismic damage scenarios assessment in the Emilia-Romagna Region

Abstract

After an earthquake, it is essential to have estimates of the potential destructiveness of ground motions and predictions of damage scenarios. These rely on the knowledge of specific features of the potentially affected area, both in terms of intrinsic characteristics (e.g. morphology, near surface geology, etc.) and elements at risk (e.g. building typologies, population distribution, etc.). Within this context, this paper describes a series of software tools developed that allow to analyze recorded accelerograms, create shake maps in terms of different ground motion intensity measures, and estimate damage scenarios. In particular, ground-motion recordings from the Italian National Accelerometric Network are processed to compute a number of ground motion Intensity Measures (IMs), while acceleration spectra are used to compare displacement demands for a series of equivalent single degree of freedom systems, derived from pushover analyses on a series of representative buildings, by using simplified methods (e.g. N2, CSM, IN2, etc.). The IMs calculated from the recordings at the various stations are used, together with attenuation and spatial correlation models, to obtain shake maps, using different criteria for quantifying site effects. These maps are used together with regional census data and various fragility models to estimate damage scenarios, using a Monte Carlo simulation approach.