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The Central Italy earthquake sequence nominally began on 24 August 2016 with a M6.1 event on a normal fault that produced devastating effects in the town of Amatrice and several nearby villages and hamlets. A major international response was undertaken to record the effects of this disaster, including surface faulting, ground motions, landslides, and damage patterns to structures. This work targeted the development of high-value case histories useful to future research. Subsequent events in October 2016 exacerbated the damage in previously affected areas and caused damage to new areas in the north, particularly the relatively large town of Norcia. Additional reconnaissance after a M6.5 event on 30 October 2016 documented and mapped several large landslide features and increased damage states for structures in villages and hamlets throughout the region. This paper provides an overview of the reconnaissance activities undertaken to document and map these and other effects, and highlights valuable lessons learned regarding faulting and ground motions, engineering effects, and emergency response to this disaster.

Background: Several studies showed important differences in the interpretation of spirometry based on different reference values, in particular by comparing European Respiratory Society (ERS) 1993 and Global Lung Function Initiative (GLI) 2012. The validation of new reference values in local populations is essential before they can be used in an appropriate manner. This study aimed to investigate the fit of GLI reference values in a healthy Italian working population. Methods: Spirometry data were collected in 1355 workers during their health surveillance medical examination conducted for exposure to chemical and biological risk factors. A single portable spirometer that met the ATS/ERS recommendations for occupational testing was used and calibrated daily. Results: Average z-score were −0.13 (with a median of −0.17), −0.25 (with a median of −0.24), and 0.18 (with a median of 0.17) for FEV1, FVC, and FEV1/FVC ratio, respectively. Considering only the normal-weighted workers, the average z-scores were −0.07 (with a median of −0.16), −0.15 (with a median of −0.16), and 0.07 (with a median of 0.02) for FEV1, FVC, and FEV1/FVC ratio, respectively. Conclusions: GLI 2012 reference values fit the Italian data satisfactorily, resulting as more accurate than ERS 1993, especially in women, normal-weighted subjects, aged 30−50 years, and for height < 165 cm.

To assess the seismic performance of slopes, the simplified displacement-based methods represent a good-working balance between simplicity and reliability. The so-called uncoupled methods permit to account for the effects of deformability and ductility by computing separately the dynamic site response and the sliding block displacements. In this paper the procedure proposed by Bray and Rathje (1998) was revised and adapted to Italian seismicity on a set of subsoil models, representative of the different soil classes specified by the Italian and European Codes. The relationship expressing the decrease of the equivalent acceleration with earthquake/soil frequency ratio was then obtained by means of dynamic 1D seismic response analyses. Statistical correlations between calculated Newmark displacements, significant ground motion parameters and the critical acceleration ratio were also derived. To estimate the reference ground motion parameters necessary for the full implementation of the proposed procedure, literature predictive equations, calibrated on strong motion records of international databases, were revised for the Italian seismicity. These ground motion prediction equations, together with simplified displacements relationships, allowed for developing an original quick procedure to evaluate the seismic slope performance by specifying the probability of exceedance of a threshold displacement, based only on few seismic input motion parameters.

The Central Italy earthquake sequence initiated on 24 August 2016 with a moment magnitude M6.1 event, followed by two earthquakes (M5.9 and M6.5) on 26 and 30 October, caused significant damage and loss of life in the town of Amatrice and other nearby villages and hamlets. The significance of this sequence led to a major international reconnaissance effort to thoroughly examine the effects of this disaster. Specifically, this paper presents evidences of strong local site effects (i.e., amplification of seismic waves because of stratigraphic and topographic effects that leads to damage concentration in certain areas). It also examines the damage patterns observed along the entire sequence of events in association with the spatial distribution of ground motion intensity with emphasis on the clearly distinct performance of reinforced concrete and masonry structures under multiple excitations. The paper concludes with a critical assessment of past retrofit measures efficiency and a series of lessons learned as per the behavior of structures to a sequence of strong earthquake events.