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A method for the estimation of expected annual losses under seismic action, using a component-level approach, is proposed. The method follows the general steps of current Performance-Based Earthquake Engineering approaches and two distinct alternatives are evaluated depending on how the collapse cases are identified. Results are compared with a commonly implemented structure level approach, showing that the latter presents an upper bound in loss estimation. The accuracy of simplified structural analysis alternatives, such as nonlinear static procedures, is also evaluated. The method is found to be suitable for economic loss assessment under seismic hazards, producing performance measures easy to understand for different decision makers. [ABSTRACT FROM AUTHOR]

Monotonic and shaking table tests are performed using strip footings placed near a model slope. Test results indicate that footing restraint conditions affect the seismic response of near-slope footings, in terms of amplification factor and critical peak ground acceleration (PGA). The theoretical seismic bearing capacity correction factor (ηγe) vs. seismic coefficient (kh) relationships based on pseudo-static methods are in good agreement with the experimental values of ηγe provided that correction factors for load inclination, load eccentricity, footing set-back are accounted for. Furthermore, a correct empirical relationship between kh and PGA is vital in applying theoretical ηγe in earthquake engineering practices. [ABSTRACT FROM AUTHOR]

Prior to modern seismic codes, several road bridges were not designed for earthquakes in many moderate seismic regions. The seismic performance of these bridges is questionable. A portfolio of 30 non-seismically designed bridges is compiled for seismic reliability assessment. Fragility analysis is conducted, and the reliability of each structure is determined considering typical moderate seismic areas. The study shows that slab and multi-girder bridges with elastomeric bearings perform worse, whereas girder bridges with conventional bearings and multi-girder bridges with monolithic joints have better behavior. It is also shown that seismic design per Eurocode 8 leads to a reliability index of ~2. [ABSTRACT FROM AUTHOR]

This study investigates the seismic response of reinforced concrete buildings designed according to the current Italian building code. Number of stories, site hazard, presence and distribution of masonry infill panels, and type of lateral resisting system are the key investigated parameters. The main issues related to design and modeling are discussed. Two Limit States are considered, namely Global Collapse and Usability-Preventing Damage. The main aim of the study is a comparison between the seismic response of the buildings, investigated through nonlinear static and dynamic analyses. Irregularity in the distribution of infill panels and site hazard emerge as the most influential parameters. [ABSTRACT FROM AUTHOR]

This paper reports on results of nonlinear analyses performed within the RINTC project on an RC building isolated with different systems (High Damping Rubber Bearings, High Damping Rubber Bearings and Flat Sliding Bearings, Friction Pendulum System) and designed according to the Italian design code. The seismic response has been evaluated under different seismic input levels of two sites with different hazard and by considering two Limit States: Global Collapse and Usability-Preventing Damage. The influence of seismic stoppers and modelling uncertainties is also evaluated. Results permit to compute the implicit collapse risk and to identify critical aspects of current design procedures. [ABSTRACT FROM AUTHOR]

In this study, industrial single-story RC precast buildings are investigated. Twenty-four case studies have been considered, in which the column height, the beam spans and the seismic hazard level are varied. The seismic design of the selected case studies is performed according to the Italian building code and additional technical documentation. Three-dimensional nonlinear models are defined to perform static and dynamic analyses for the seismic assessment of the selected case studies. Demand/capacity ratios in terms of the selected engineering demand parameters are computed for ten increasing values of the seismic input return period. [ABSTRACT FROM AUTHOR]

This article describes the structural design, nonlinear modeling, and seismic analysis of prototype single-storey non-residential steel buildings made of moment-resisting portal frames in the transverse direction and concentric braces in the longitudinal direction. Various design parameters (building geometry, seismic hazard, foundation soil category) and different modeling assumptions (bare frame model, model including cladding elements, ground motions including vertical accelerations, and modeling uncertainties) were considered to investigate their effects on the simulated seismic performance. [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]