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A prominent challenge in performance-based earthquake engineering is to select a suitable set of ground motions records with which to perform probabilistic seismic assessment of structures. The mos...

A challenging task in earthquake engineering is investigation of engineering demand parameters under regional records of large earthquakes due to inherently low frequency of these events. Use of si...

This paper presents an overview of the ROSSINI project, illustrating its general objectives and how it places itself within the overall field of seismic risk-aware navigation systems. In particular, it describes the use of a sensor array for the integrated risk-aware navigation in industrial plants at risk of NaTech accidents. The integration of structural and environmental risks estimated and measured in different ways is presented as part of an integrated risk identification and evaluation (RIE) module. This module will be used along with a series of logic to combine and map the possible risks spatially within an industrial plant’s layout. It is seen how this information can then be used to not only compute the safest path to safety for a worker located within such a plant but also how mobile communications can be used to aid and guide them in different scenarios. All of this stems from the use of a sensor array network in a relatively novel way within this particular context. The paper discusses the progress to date and presents the ongoing results of a pilot case study application of the system to an industrial plant facility in Italy.

The literature on energy-based seismic design and assessment methodologies of structural systems mostly relies on real ground motion datasets. However, certain bias exists due to lack of homogeneity in available ground motion datasets. In this study, a large set of ground motions is simulated. Next, the effects of various parameters on seismic behavior of SDOF systems in terms of energy are studied using nonlinear time history analyses. The stochastic finite-fault simulations are performed on the western parts of North Anatolian Fault zone in Turkey. Input, damping and hysteretic energies are the considered parameters. Results reveal that seismic energy is a more suitable parameter when compared to the other physical parameters such as seismic displacement and force. However, it is important to dissipate the estimated input energy through damping and inelastic action. Finally, parametric seismic analyses using simulated ground motions yield realistic results since these records provide variability in seismic demand.

The collapse of a relevant portion of the Polcevera river viaduct, located in Genoa (Italy) and also known as Morandi Bridge, is herein object of a numerical investigation. The bridge was designed in the early 1960s by Riccardo Morandi, a well-known Italian engineer, and opened to the public in 1967. The collapsed part of the bridge essentially comprised an individual self-standing structure spanning 171 m and two simply-supported connecting Gerber beam systems, each spanning 36 m from the self-standing structure to the adjacent portions of the bridge. A previous investigation, by Calvi et al. (Calvi et al. in Struct Eng Int 29:198–217, 2019), indicated that the collapse of the bridge could have potentially been triggered by a sudden loss of effectiveness of one stay (e.g. due to the failure of either the deck-stay or the antenna-stay connections), which in turn would have induced a flexural–torsional-shear failure of the bridge deck. In the current work, therefore, the attention is turned into a more detailed study of the latter, through the employment of detailed Finite Element Analysis modelling, with a view to corroborate, or not, the results of the aforementioned previous study. As in the latter, the development of such model was based entirely on publicly available material that has so far been rendered online accessible. It is shown that should the support provided by one of the bridge stays be removed, the ensuing flexural–torsional-shear demand on the deck would be such that the latter would be led to the type of collapse observed in the field.

Liquid storage tanks are widely used in the industry and can contain not only harmless substances but also various ones that can be explosive and toxic or pollutant, thus implying that both the structure and the content must remain safe and operational under different types of loading. The same applies to any tank-connected plant system/item. Yet, past earthquakes repeatedly demonstrated that even if structural damage is prevented in the shell, severe occurrences may still be observed due to sloshing phenomena, which drive the tank-fluid system response with high impacts in case of accidental release of chemicals. Therefore, this paper studies an energy dissipation system consisting of floating roof and external dampers that are utilized to control liquid vibration by augmenting the level of damping. In order to evaluate its effectiveness at the design-level earthquakes, a series of explicit nonlinear dynamic analyses have been performed, and comparisons are provided between floating roofed steel cylindrical tanks equipped with supplemental devices and counterparts without them. Changes in seismic performance because of geometrical variations in the tank (i.e. aspect ratio) and seismic input (i.e. far and near field earthquakes) have been quantified by means of experimentally validated numerical models that account for material and geometrical nonlinearities, as well as for fluid-structure interaction in an explicit manner. Shake-table tests available in the literature have been simulated, and the proposed modelling criteria show a good fit with experimental data on two tank specimens. Analysis data sets involving three tank geometries reveal that even if the dissipation system targets mainly large-capacity tanks, it can be effectively used to enhance the performance of any system, reducing the sloshing wave height which can be excessive especially when the tank is subjected to severe near field ground motions.

For the last two decades, there has been a growing and remarkable attention on the energy-based design and assessment approaches for structural systems. These approaches have also been implemented to some of the national seismic design codes as alternative methods in addition to the traditional force-based design methodology. The underlying research has been often carried out by using actual ground motion records taken from many different earthquakes all over the world. However, such an attempt impairs the validity of the obtained results since it is generally not possible to construct a homogeneous ground motion record database with well-distributed source and ground motion parameters. In this study, in order to overcome the aforementioned disadvantage, a large set of simulated ground motion records are used in a parametric study to examine the influence of different intensity measures on the energy-based response of simple structural systems, i.e. single-degree-of-freedom (SDOF) systems. A set of ground motions is formed from simulation of potential events with a certain moment magnitude range, source-to-site distances and soil conditions. The simulations are performed on active faults around Erzincan city center located on the Eastern sections of North Anatolian Fault zone in Turkey. The output parameters are input energy, hysteretic energy and damping energy. The results show that the energy is a relatively stable parameter when compared to other response parameters. Hence energy seems to be a good candidate to be used in seismic design and assessment approaches.