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The seismic assessment of the vulnerability of existing public structures, especially school buildings, is a crucial issue in seismic prone countries. Recently, several national and regional programs and activities have focussed on the mitigation of Italian public buildings. They promote the scheduling of public buildings' structural safety assessment and, when needed, the design and execution of strengthening interventions. Nevertheless, the three strong earthquakes that occurred in the last decade in Italy, Abruzzo (2009), Emilia (2012), and Central Italy (2016), confirmed the vulnerability of school buildings and the social importance of their quick re-opening after a damaging earthquake. In the present paper, the activities carried out on 1514 school building structures in the aftermath of the 2016 Central Italy earthquake sequence are reported and analysed. According to survey data collected by post-earthquake usability inspections, the paper analyses the school buildings characteristics, damage level and extent to structural and non-structural components as well as the correlation between seismic intensity and observed damage. [ABSTRACT FROM AUTHOR]

The paper illustrates the construction of abacuses for the semi-quantitative assessment of stratigraphic seismic amplification phenomena, applicable in the eastern Abruzzo region (central Italy). The abacuses provide three expected Amplification Factors (Fas): Fa0.1-0.5, Fa0.4-0.8, Fa0.7-1.1, performed as the ratio between the integral of output and input, in the mentioned time intervals, considering the acceleration response spectra. The choice derives from the fact that these parameters are better correlated to the response of the buildings, characterised by their own different periods. To prepare the abacuses, a procedure was adopted that took into consideration the geological analysis of the area, the collection of all the available geophysical and geotechnical data, the choice of the seismic inputs representative of the seismic hazard, the identification of the main seismic stratigraphic sequences and the numerical analysis aimed at evaluating the Fa. The abacus consists of a series of tables prepared in order to take account of the stratigraphic variability in the area, as a function of the basic seismic hazard level and the vibration period interval to calculate the Fa. By knowing the stratigraphic and mechanical characteristics of the site and using the abacuses, the values of the Fa are obtained. [ABSTRACT FROM AUTHOR]

Seismic events that struck Italy in the last years had a dramatic impact on historical and cultural heritage. Damage occurred on existing masonry buildings, in particular on churches, stressed out the need to better understand the seismic behaviour of this type of constructions as well as to define more appropriate mitigation strategies to be applied at large scale. This study deals with a predictive methodology for vulnerability assessment of churches in large territorial areas. Focusing the attention on three naves churches of Abruzzi, the paper proposes modifications and integrations of an existing methodology taken by literature. These modifications are defined through a calibration procedure based on damage observation of 64 three naves churches located at different distances from the epicentre of the 2009 earthquake. The proposed model is employed to predict damage level distribution for different earthquake intensities, allowing fragility curves to be plotted and therefore potential damage scenarios to be represented. [ABSTRACT FROM AUTHOR]

Abstract: A procedure for assessing the seismic vulnerability of residential buildings is presented along with the results of its application in an Italian town in Abruzzo (Celano Aq). This procedure is part of a methodological proposal which includes specific studies on expected seismic inputs and site effects analyses. The procedure is based on a simplified collection of data, such as typological features and factors concerning the seismic behaviour of buildings, and provides an estimate of seismic vulnerability and an expected damage forecast using fragility curves. The instruments and methods used for the Celano project are an updated and improved version of those applied to previous vulnerability investigations. This paper demonstrates how this procedure can meet the objectives of the integrated methodology proposed. In fact, the information that can be obtained using this procedure—state of vulnerability, risk analyses and GIS presentations of damage scenarios—could be used in urban planning to reduce seismical risk. [Copyright &y& Elsevier]

SUMMARY On 2009 April 6 a Mw = 6.3 earthquake struck the Abruzzi region (Central Italy) and caused severe destruction in L'Aquila and the surrounding area. In this work we present a Finite Element analysis of the event based on a realistic complex 3-D model, accounting for topographic relief and rheological heterogeneities deduced from local tomography. Finite Element computed Green's functions were implemented in a linear inversion of GPS coseismic displacements, to retrieve the slip distribution on the rupture plane. The inverted slip models basically agree with previous studies carried out on homogeneous domains, but reveal the presence of a single high slip patch, whereas half-space or 1-D approaches obtain a more complex slip pattern. Our results point out that the introduction of 3-D features significantly influences the obtained source model, suggesting a trade-off between domain complexities and source details. [ABSTRACT FROM AUTHOR]