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The paper presents and discusses seismic fragility functions of code-conforming buildings in Italy. The structures under consideration are taken from those considered by a large Italian research project (RINTC), aiming at evaluating the seismic reliability of new-design buildings. Design refers to a variety of structural typologies (i.e. un-reinforced masonry, reinforced concrete, steel, and precast concrete buildings) and configurations (e.g. number of stories, floor plan, and the presence of infills), as well as to sites with different hazard levels and local site conditions. The seismic fragility of the structures is evaluated via multiple-stripe nonlinear dynamic analysis using the equivalent-single-degree-of-freedom (ESDoF) systems calibrated based on pushover analysis of the three-dimensional structural models. The seismic response of the ESDoF models is also validated in terms of demand-capacity ratio and risk of failure compared to those of the three-dimensional structural models. Along with providing fragility curves for the buildings located at high-hazard sites, the study discusses the issues that significantly affect the fragility assessment for those located at low-to-mid hazard sites. [ABSTRACT FROM AUTHOR]

GPS measurements recorded at active sites in central Italy during the seismic events of greatest magnitude (24 August, 26 and 30 October 2016) were processed in kinematic mode according to the Precise Point Positioning (PPP) technique. The resulting data were the displacements and, by derivation with respect to time, the velocities and instantaneous horizontal accelerations. Elastic response spectra along the orthogonal walls of the site (if the GPS antenna was fixed to a building) or along the geographical directions (if the antenna was fixed to the ground) were obtained from the derived accelerations. The maximum amplitudes, i.e. "peak vibrations", were then extracted from the response spectra. These peaks, unlike the co-seismic movements, represent the maximum instantaneous vibrations recorded following the "shock" produced by the seismic waves and thus are representative of both the discomfort perceived by the populations and the structural damage. This study shows that GPS is becoming an increasingly important tool to measure and monitor the dynamic responses of a structure. The results also provide a complete picture of the displacements induced by the seismic sequences in the earthquake-affected areas, leaving unresolved some questions concerning the localization of the phenomena and the causes of the structural deformations. [ABSTRACT FROM AUTHOR]