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The shell structures are commonly used in many civil and industrial and long-span logistic applications. In this research we simply start by applying a degenerated finite element continuum approach. Then we propose a new alternative formulation by splitting the shear energy into two main components, the first one exactly integrated, whereas the second reduced integrated in a proper way. In this numerical and analytical research we present this advanced new approach (herein named penalty partial reduced selective integration) by adding weight coefficients to the splitting energy terms. As a consequence of this formulation, the unwanted locking events are definitively eliminated. A wide range of real and analytical examples, from scientific literature and practical engineering shell design situations, are analyzed and deeply investigated to better understand the level of accuracy and effectiveness of the formulation proposed. Furthermore, comparisons withwell defined and established shell finite elements are made just to yield insight into the predictive capability of the penalty partial reduced selective integration, herein proposed and studied. Hence many examples are used to test this new formulation in order to analyze the numerical behavior of the approximate solution in dependence of the splitting parameters. A simple kind of methodological rules for choosing these numerical non-dimensional parameters are also given.

The prevalence of elevated reinforced concrete tanks is widespread across Italian water distribution networks, particularly in flat or low-relief areas. Primarily constructed by the late 1970s, these tanks often suffer from outdated hydraulic efficiency, unable to cope with the increasing urban water demands. With rising construction costs, the economic advantage has shifted toward underground tanks, leading to the decommissioning of many elevated tanks. Despite being obsolete, elevated tanks from the 1960s and 1970s still stand in densely urbanized regions. However, demolishing them may prove less cost-effective than retrofitting to restore their original structural capacity. The widespread presence of these structures, coupled with their susceptibility to decay from weathering and poor maintenance, necessitates a comprehensive assessment of their resilience against gravitational and lateral forces, including seismic activity. Consequently, there is a pressing need to develop an analysis and verification methodology, particularly focused on seismic resilience, tailored to existing elevated tanks. These structures, distinct from conventional reinforced concrete frames, are primarily designed to withstand vertical forces, emphasizing the importance of optimizing material usage in their retrofitting efforts. [ABSTRACT FROM AUTHOR]

The current investigation delved into the seismic analysis, design intricacies, and assessment of the response of elevated steel containment tanks when supported by concentrically braced frames. The primary focus was placed on comprehending the behavior of the supporting structure, recognizing its heightened vulnerability to damage under horizontal excitation—insights gleaned from reconnaissance teams studying earthquake aftermaths worldwide. A specific case study unfolded featuring a steel concentrically braced frame as the supporting structure, aligning with prevalent industry norms. Throughout the entire process, spanning design phases, seismic vulnerability assessments, and response evaluations, special emphasis was placed on the internal fluid sloshing phenomena. This nuanced consideration plays a pivotal role in shaping the dynamic response of the system. The study introduces two distinct design methods: the first method aligns with relevant international codes, while the second method innovatively incorporates the compressive strength of the braces into its approach. To evaluate the dynamic response of the elevated tank, both linear and nonlinear advanced analyses were employed. The comparative analysis of various strategies underscores the impact of the chosen design methodology on the overall system response. This multifaceted exploration aims to contribute valuable insights to the seismic resilience and design optimization of elevated steel containment tanks, furthering the understanding of their performance under seismic forces. [ABSTRACT FROM AUTHOR]

Following recent earthquakes, precast buildings exhibited a strong seismic vulnerability related to the presence of closure external panels. The aim of this work is to simulate the seismic response of existing single-storey precast buildings in the case of explicit modelling of external panels. The considered case studies are precast buildings representative of the Italian building stock in the 1970s and 1990s, characterised by two different cladding systems, namely, masonry infills and reinforced concrete precast panels, respectively. The explicit modelling of infills and panels, typically introduced solely as participating masses, provided insights into their actual contribution on the global structural behavior. [ABSTRACT FROM AUTHOR]

This paper presents a general seismic classification procedure for acceleration‐sensitive non‐structural elements (NSEs) based on seismic qualification shake table testing and provides an application example for electrical cabinets in Italy. The proposed seismic classification procedure requires the definition of a set of required response spectra (RRS) for qualification shake table testing defined at different seismic hazard levels and the definition of a formal procedure to generate a test input motion. Each required response spectrum at a given seismic hazard level is then linked to different class levels and the requirements that an NSE should present to achieve each class level are defined. Using this framework, a seismic classification procedure for NSEs is developed for Italy, in which, the RRS are defined according to a peak floor spectral acceleration seismic hazard map of the territory so as to predefine regions in which an NSE belonging to a given class can be installed or not according to either a life safety performance objective or a continuous operation performance objective. Also, the limitations of the proposed seismic classification procedure are outlined. Finally, a nominal application example is presented in which four electrical cabinet specimens were tested on a shake table and their class levels were defined. The results of the application example are used to nominally show how the proposed classification procedure could be applied to discriminate between different types of the same NSE depending on the specific desired application. [ABSTRACT FROM AUTHOR]

The assessment of seismic risk for critical and strategic structures like schools and hospitals remains crucial, even in regions with low seismic activity. Presently, operational school buildings in Sri Lanka are primarily designed to handle gravitational loads without considering capacity-based design principles. Consequently, these structures may lack the necessary lateral resistance to mitigate potential damage or collapse during future earthquakes in Sri Lanka. Hence, conducting seismic risk assessments for such school buildings is imperative to ensure the safety of their occupants. In this research paper, we utilize a recently developed probabilistic seismic hazard map for Sri Lanka to evaluate seismic risk. We employ two nonlinear 3-D finite element models of school buildings created in OpenSees. Incremental Dynamic Analysis is conducted using a well-established set of ground motions, continuing until the structure approaches the point of collapse, to determine the probability of collapse prevention. Subsequently, we develop fragility functions for two limit states, immediate occupancy, and collapse prevention. These fragility curves are then used to compute the probability of exceeding these limit states, aiding in the assessment of the structural safety of the school buildings. A key outcome of this analysis reveals a general trend of increased damage probabilities as the number of stories in the buildings increases despite the distinct structural characteristics of each building. It is also important to note that the disparities between the immediate occupancy and more severe damage cases, such as collapse prevention, are notably pronounced in both two- and three-story school buildings. [ABSTRACT FROM AUTHOR]

Monitoring of non-structural elements is not usually implemented, despite the seismic vulnerability of these components and the significant cost associated with their replacement in case of damage. By exploiting the limited cost of commercial sensors, accelerometers were installed in an existing building to compare accelerations applied to non-structural elements in case of an earthquake with critical acceleration thresholds. The exceedance of these thresholds would indicate a possible danger for the occupants and the need for a more detailed inspection of the element, guiding prioritisation strategies in the aftermath of the earthquake. Furthermore, the real-time probabilistic assessment of potential damage to non-structural elements can serve to identify escape routes and facilitate rescue operations. Critical acceleration thresholds were defined from probabilistic considerations on the expected seismic performance of each typology of non-structural element, described by appropriately selected fragility curves. The feasibility of the proposed procedure was tested by comparing the identified acceleration thresholds with the design values of floor acceleration provided by the Italian Building Code. As a further application, critical acceleration values of the different non-structural elements were compared with a set of real floor acceleration values recorded at the top level of reinforced concrete buildings, highlighting critical non-structural element typologies. [ABSTRACT FROM AUTHOR]

Building Information Modelling is receiving increasing attention as an emerging technology for enhancing the life‐cycle performance of facilities. The cooperation between all professionals involved in the construction chain allows to reproduce digital twins of the structures including information related to different disciplines, such as structural and architectural aspects. In this context, the use of Building Information Modelling, combined with an automatic tool to predict risk indices, could be particularly useful when dealing with existing bridges due to the significant structural deficiencies recently demonstrated by numerous bridge collapses worldwide. This paper explores the development of a BIM‐based procedure to bring greater value in the design, construction, maintenance, and inspection stages. The procedure is applied to existing bridges and it allows to estimate a structural risk prioritization class of bridges according to maintained activities, periodical inspections, structural detailing and modelling uncertainties. The automatic BIM‐based tool uses a workflow developed in Dynamo, and is able to automatically update the structural risk class and to provide warning if the structural safety index exceed defined thresholds. [ABSTRACT FROM AUTHOR]

An adequate seismic protection of steel storage tanks of industrial, chemical and petrochemical plants is essential since potential consequences of failures, besides the economic losses, can be catastrophic for the environment and for people living nearby. Among the most common damages suffered by steel tanks in recent earthquakes, there are the elephant‐foot‐buckling of the perimeter wall and the tanks' uplift or overturning. Due to the uncertainties related to the estimation of the mechanical properties of filled tanks and related seismic loads (i.e. dynamic overpressures generated by the content), conventional design approaches may lead to unsafe or, on the contrary, oversized solutions. Among effective alternatives, base isolation through Curved Surface Slider isolators (CSSs) offers some valuable advantages like high load bearing and displacement capacity with compact dimensions, independence of the oscillation period on the supported mass, and minimisation of torsional effects. Despite being neglected by most common commercial FEM codes, as a drawback, recent studies pointed out that the initial peak of friction force at CSSs' motion breakaway can lead to significantly increased lateral deformations and accelerations of the superstructure. Within this framework in this study, a refined numerical model is developed in OpenSees FEM code, and an exhaustive parametric study is carried out to investigate the effect of the breakaway on isolated tanks providing some useful insights for the selection of the most suitable isolators. [ABSTRACT FROM AUTHOR]

There are many applications in buildings in which precast pre-stressed hollow-core (HC) slabs are subjected to shear, torsion, or combined shear and torsion. Nonetheless, extruded HC units contain no transverse reinforcement, being inherently vulnerable to brittle failure modes due to shear and torsional actions. In previous work by the authors, a finite element (FE) modelling approach for HC units failing in shear was developed and validated against experimental test data. This paper aims to extend the applicability of the proposed FE approach to help improve the understanding of the torsional behavior of HC units. For this purpose, the developed model is further validated against experimental data available in the literature and then used to predict the torsional capacity of New Zealand-specific 200 mm deep HC units. Results suggest that the FE model is capable of predicting the capacity of HC slabs with and without eccentricity of the applied vertical load. Finally, the numerical results are used to evaluate the performance of available simplified analysis approaches for assessing the torsional capacity of HC units, which are found to be nonconservative if used with expected material properties. [ABSTRACT FROM AUTHOR]

Old precast buildings are often characterized by poor detailing that may hamper the structural performance, particularly in the case of earthquakes. This is essentially related to: (i) a limited past knowledge of seismic design and behaviour, also reflected in past building codes; (ii) the evolution of seismic zonation of the Italian territory. The aim of this work is to assess the probabilistic seismic vulnerability with respect to the usability preventing damage and global collapse performance levels of four existing single-story precast buildings designed in accordance with past Italian building codes from 1960s to 1990s in three sites with increasing seismic hazard. [ABSTRACT FROM AUTHOR]

The structural safety of the infrastructure stock is an important issue in modern seismic performance assessments. Following recent seismic events, reports have highlighted the increased vulnerability of physical infrastructural assets, particularly for many bridges across the Italian road and motorway network. Italy possesses one of the most complex and intricate road systems in Europe which was constructed across irregular territories in terms of plan and elevation and of varying dimensions. As such, a comparative case study is presented herein. This case study aims to characterise the seismic vulnerability of the Vizzana-Zampogna viaduct which is part of the A15 Parma-La Spezia motorway, near the locality of Selva Bocchetto. The viaduct is considered representative of the 1970s construction period. It is approximately 342 m in length and is characterized by a flat curvilinear prestressed concrete deck consisting of 15 spans simply supported on reinforced concrete piers. To better understand the seismic structural response of the individual piers of the viaduct, a "multi-modal" nonlinear static analysis was developed, which allows the effects of sectional stresses relative to the variable load profiles of the single modes to be combined through the quadratic modal combination, and to be compared with the relevant limit state. The research aims to qualitatively identify the piers most vulnerable to seismic action and to study the effects that are induced by introducing variable loads and intensity scenarios of different earthquakes. [ABSTRACT FROM AUTHOR]

Nonstructural elements (NEs) are generally defined as elements typically housed within buildings/facilities that are not part of the structural system. Nonstructural elements are often classified as architectural elements, mechanical/electrical/hydraulic systems, and building contents. Nonstructural elements are often associated with critical seismic risk, due to their high vulnerability and exposure to seismic actions, especially for critical facilities such as hospitals and nuclear plant facilities. Accordingly, the combination of major exposure and vulnerability makes NEs extremely critical in terms of seismic risk even for low to moderate seismicity. The paper reviews and evaluates the main international testing approaches and protocols for the seismic assessment of NEs by means of experimental methods, which are referred to for seismic qualification. Existing test protocols are technically analyzed considering quasi-static, single-floor dynamic, and multi-floor dynamic procedures, supplying technical and operative guidance for their implementation, according to the latest advances in the field. The study proposes novel perspectives and a unified approach for the seismic assessment and qualification of NEs. The technical recommendations lay the groundwork for a more robust and standardized testing and qualification framework. In particular, the provided data might represent the first step for developing code and regulation criteria for the experimental seismic assessment and qualification of NEs. [ABSTRACT FROM AUTHOR]

Robustness of reinforced concrete (RC) structures is an ongoing challenging research topic in the engineering community. During an extreme event, the loss of vertical load-bearing elements can activate large-deformation resisting mechanisms such as membrane and catenary actions in beams and floor slabs of cast-in-situ RC buildings to resist gravity loads. However, few studies have been conducted for precast concrete (PC) buildings, especially focused on the capacity of such structures to withstand column loss scenarios, which mainly relies on connection strength. Additional resistance resource and alternate load paths could be reached via tying systems. In this paper, the progressive collapse resistance of a PC frame building is analyzed by means of nonlinear dynamic finite element analyses focusing on the fundamental roles played by beam-to-column connection strength and tying reinforcement. A simplified modelling approach is illustrated in order to investigate the response of such a structural typology to a number of sudden column-removal scenarios. The relative simplicity of the modelling technique is considered useful for engineering practice, providing new input for further research in this field. [ABSTRACT FROM AUTHOR]

Felt material is sometimes employed in precast wall‐slab‐wall structures featuring no mechanical devices for the wall‐slab connection. This implies that the frictional properties of these felts should be high enough to permit horizontal lateral forces on a building to be carried through them, preventing the sliding of slabs on precast walls and eventually their unseating. In light of this, friction testing of fabric felt material has been undertaken, combining triplet‐monotonic and cyclic‐symmetric tests, with a view to characterize this material, allowing not only an estimate of the shear force transferred, in actual buildings, between the slabs and the precast walls underneath them, but also a likely force‐displacement relationship that may be employed in numerical modeling efforts. Comparisons with data from a recent full‐scale building test corroborate the results obtained by the two‐step experimental investigation presented in this paper, thus adding further weight to the modeling recommendations herein provided. [ABSTRACT FROM AUTHOR]

Wall‐slab‐wall buildings, in precast configuration or not, are relatively widespread in many European and non‐European countries, independently of the level and nature of seismic hazard to which the country is prone. Thus, this building archetype, featuring no columns or beams, but only slabs and walls, can be equally found both in areas characterized by potentially high‐damaging tectonic earthquakes and regions where small‐to‐medium‐size natural/anthropogenic seismic events would instead be expected. Notwithstanding the above, relatively little information has been offered so far on the seismic response/performance of these structures and their key components, which in case of a precast system/layout will inevitably be the connections between the structural elements. To partly fill such knowledge gap, this paper concerns the latter configuration and deals with experimental testing of panel‐to‐panel joints, which are not only two‐way links but also three‐way connections because it is very common for such structures that contiguous panels are connected to a transverse shear wall. Not surprisingly, very recent pseudostatic and shake‐table tests on full‐scale specimens, undertaken by the authors to characterize the performance of this structural system up to incipient/near collapse, have indicated how the latter panel joints are the weakest link of the system tested, thus prompting further component testing, in cyclic/asymmetric fashion, to single out the response of the joint. Monotonic and cyclic response curves of the five specimens and the counterpart damage patterns revealed that the observed flexural failure mechanism is very stable and aligns very well with that mobilized by the full‐scale building tests. [ABSTRACT FROM AUTHOR]

Computational models, which follow numerical assessment strategies codified by current European rules for shell buckling, were developed so as to study the buckling and post-buckling response of a large set of cylindrical steel thin-shell prototypes with structural openings. Behavioural changes as a consequence of variations in the cutout configuration, that is, shape, size, location and number, were predicted and the obtained numerical estimates were related to the test data of previous experiments in order to explore critical design aspects. Damage modes and axial force–axial displacement response curves were presented and discussed, decoupling the roles played by material nonlinearity and geometrical nonlinearity, as well as the contribution of initial geometrical imperfections to the buckling mechanism of axially compressed cylindrical thin shells. [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]

Floor diaphragms play several roles in the seismic response of dual systems: support vertically spanning components, transfer lateral forces to walls and frames, provide restraint to columns and walls, tie the structure together, and enable redundant load paths for lateral forces. In many buildings after events as recent as the 2010-2011 Christchurch earthquakes, floor diaphragms were unable to perform one or more of these functions, leading to extensive damage and collapse. Research consistently highlights three underlying causes: a failure to ensure the integrity of the load path, underestimation of in-plane forces, and poorly understood interactions with walls, supporting beams and RC moment frames. Most recent and ongoing research has focused on modifying the prescriptive code provisions, and indeed many codes–but not all- have been consequently updated. Such prescriptive rules, however, are not helpful for assessing existing buildings, comparing alternate means and methods, or in displacement-based design (DBD) for which a performance-based design (PBD) framework is necessary. This paper proposes a new performance-based framework for the seismic design of reinforced-concrete (RC) floor diaphragms with or without precast elements. The floor diaphragm performance limit states (LS) are re-defined in terms of the observed failure modes (FM). Results from prior research on these failure modes are used to select damage measures (DM, e.g. ‘crack width’) for pairs of FM and LS. Expressions for DMs in terms of engineering demand parameters (EDP, e.g. , ‘strain’) are derived from experimental results or from first principles. EDPs are the basic output from numerical analysis in PBD; this paper comments on the suitability of different analytical approaches. [ABSTRACT FROM AUTHOR]

This study provides a framework for investigating the seismic response of an elevated steel water tank within a reinforced concrete chimney, to assist optimal tank placement and analyse different tank geometries. Elevated tank design procedures in different guidelines and codes are adequate for specific cases, none of which meets the exact requirements of this case study, in which the supporting structure mass is large relative to the storage tank. The tank is located at an elevation 63 m below the mid-height of the 200 m chimney, resulting in a different behavior than a simple cantilever. Furthermore, for certain H/R ratios, coupling effects may exist between the fundamental period of the chimney and that of the sloshing wave. An equivalent model is examined that is simple enough yet able to accurately produce the design acceleration, dynamic amplification, damping and torsional effects at the chosen tank location, and to capture site effects. An analysis of the tank at ground level is conducted according to AWWA D100-11. Then, the tank at elevation 63 m is analysed within the framework of three existing methods using code spectra and site-specific spectra. A novel fourth method is then proposed which, contrary to the existing methods, can accurately capture the conditions of this case study by combining the benefits of all methods. The workflow described here can be readily applied to other cases of elevated tanks for which the standard procedures are inadequate. [ABSTRACT FROM AUTHOR]

The following paper presents the design and verification steps of tall steel frame structures with braced core, belt and outrigger trusses. The two case study structures refer to sky scrapers of 180m and 300m respectively, located in Istanbul, Turkey. The main objectives of this study are two: firstly designing the buildings through multilevel structural analysis, secondly to compare the results, in terms of seismic response, between response spectrum analysis (RSA) and nonlinear time history analysis (NLTHA). Such comparison has been made with the intention of investigating the relationship between the structure height and the accuracy of RSA predictions, considering that the latter approach tends to underestimate the influence of higher mode effects. In conclusion the capacity curves of the two structures, developed using incremental nonlinear dynamic analysis, are presented as an ulterior way to assess the seismic capacity of such type of high-rise structural systems. [ABSTRACT FROM AUTHOR]

In the last decades, particular attention has been paid to the seismic vulnerability of existing reinforced concrete buildings designed for gravity loads only. Such buildings, designed before the introduction of capacity design in modern seismic codes, are very common, particularly in seismic prone countries of the Mediterranean area. Due to poor detailing and lacking of capacity design principles, high vulnerability has been highlighted in several past studies. In this article, inadequate seismic response and peculiar damage pattern are investigated by means of shake table tests performed on a 1:2 scaled 3-story infilled prototype. Particular attention is given to the role of beam-column joints and frame-panel interaction. The effectiveness of the EC8-based assessment approach is then evaluated; both linear and nonlinear numerical models, with different levels of sophistication, have been implemented in order to explore their behavioral aspects. [ABSTRACT FROM PUBLISHER]

Field observations following the May 2012 Emilia, Italy, earthquakes have revealed the seismic vulnerability of storage steel tanks typical of the past Italian design practice, highlighting structural deficiencies observed during previous events in other areas and mostly related to lack of structural seismic design and detailing, lack of redundancy, and inadequate anchorage design and execution. Damage was disproportionately high, considering the moderate size of the events (MW = 6.11 and MW = 5.96 on 20th and 29th May, respectively). Failure modes observed are reported and classified. Comparison is provided with the results of high-definition finite element (FE) dynamic simulations, performed on tanks representative of those inspected. Numerical analyses, accounting for material and geometrical nonlinearities, at the element level, as well as for fluid-structure interaction through highly nonlinear methods, were able to capture the stress/strain concentrations that caused them to collapse. Elephant's foot and diamond buckling induced by hydrodynamic pressures as a result of inertial forces imparted during the earthquakes were reproduced, as well as shear-buckling failure of leg-supported tanks or sliding of unanchored systems. [ABSTRACT FROM AUTHOR]

Shaking-table experiments of relatively large-scale specimens play a fundamental role in deepening our understanding of seismic response of existing structures and verification of numerical models. However, and in apparent contradiction, the preparation of such a dynamic laboratory experiment requires a-priori advanced numerical simulations, necessary to both fine-tune the test specimen properties and calibrate the input motion, as a function of the objectives of the test and capabilities and characteristics of the shaking table. This research thus concerns the development of a fibre-based finite elements model of a halfscale 3D reinforced concrete frame tested under dynamic conditions at the European Centre for Training and Research in Earthquake Engineering (EUCENTRE, Pavia, Italy). Since this reduced-scale specimen is very much based on a full-scale counterpart previously tested under pseudo-dynamic conditions at the European Laboratory for Structural Assessment (ELSA) of the Joint Research Centre (JRC, Ispra, Italy), the first part of the work consisted in verifying that the software tool employed in the numerical simulations was capable of duplicating the pseudo-dynamic real test results. Having successfully met the latter objective, the second part of the work consisted in the attempted numerical simulation of the shaking table tests, with a view to ascertain that the response of the model will be within the envisaged response targets and that the necessary input motion is compatible with the shaking-table characteristics. [ABSTRACT FROM AUTHOR]

The seismic events in Northern Italy, May 2012, have revealed the seismic vulnerability of typical Italian precast industrial buildings. The aim of this paper is to present a seismic fragility model for Italian RC precast buildings, to be used in earthquake loss estimation and seismic risk assessment by comparing two building typologies and three different codes: D.M. 3- 03-1975, D.M. 16-01-1996 and current Italian building code that has been released in 2008. Based on geometric characteristics and design procedure applied, ten different building classes were identified. A Monte Carlo simulation was performed for each building class in order to generate the building stock used for the development of fragility curves trough analytical method. The probabilistic distributions of geometry were mainly obtained from data collected from 650 field surveys, while the material properties were deduced from the code in place at the time of construction or from expert opinion. The structures were modelled in 2D frameworks; since the past seismic events have identified the beam-column connection as the weakest element of precast buildings, two different modelling solutions were adopted to develop fragility curves: a simple model with post processing required to detect connection collapse and an innovative modelling solution able to reproduce the real behaviour of the connection during the analysis. Fragility curves were derived using both nonlinear static and dynamic analysis. [ABSTRACT FROM AUTHOR]

Current codes incorporate simplified methods for the prediction of acceleration demands on secondary structural and non-structural elements at different levels of a building. While the use of simple analysis methods should be advocated, damage to both secondary structural and non-structural elements in recent earthquakes have highlighted the need for improved design procedures for such elements. In order to take a step towards the formation of accurate but simplified methods of predicting floor spectra, this work examines the floor spectra on elastic and inelastic single-degree of freedom systems subject to accelerograms of varying seismic intensity. After identifying the factors that appear to affect the shape and intensity of acceleration demands on secondary structural and non-structural elements, a new series of calibrated equations are proposed to predict floor spectra on single degree of freedom supporting structures. The approach uses concepts of dynamics and inelasticity to define the shape and intensity of the floor spectra at different levels of damping. The results of non-linear time-history analyses of a series of single-degree of freedom supporting structures indicate that the new methodology is very promising. Future research will aim to extend the methodology to multi-degree of freedom supporting structures and run additional verification studies. [ABSTRACT FROM AUTHOR]

The seismic sequence which hit the Northern Italian territory in 2012 produced extensive damage to reinforced concrete (RC) precast buildings typically adopted as industrial facilities. The considered damaged buildings are constituted by one-storey precast structures with RC columns connected to the ground by means of isolated socket foundations. The roof structural layout is composed of pre-stressed RC beams supporting pre-stressed RC floor elements, both designed as simply supported beams. The observed damage pattern, already highlighted in previous earthquakes, is mainly related to insufficient connection strength and ductility or to the absence of mechanical devices, being the connections designed neglecting seismic loads or neglecting displacement and rotation compatibility between adjacent elements. Following the vulnerabilities emerged in past seismic events, the paper investigates the seismic performance of industrial facilities typical of the Italian territory. The European building code seismic assessment methodologies are presented and discussed, as well as the retrofit interventions required to achieve an appropriate level of seismic capacity. The assessment procedure and retrofit solutions are applied to a selected case study. [ABSTRACT FROM AUTHOR]

The need for affordable housing in developing countries requires the development and use of new structural systems that allow easy, fast, and cheap construction while providing a sufficient seismic performance to protect the life and belongings of the population. In this regard, structural wall systems based on ferrocement have proved to be a feasible option to meet these criteria. Ferrocement is a construction system composed of mortar (i.e., cement, sand, and water) and thin and closely spaced steel reinforcement (i.e., small rebars, welded mesh, hexagonal wire mesh, metal fibers, etc.). This dataset corresponds to the hysteretic response of a ferrocement wall subjected to an increasing in-plane fully-reversed cyclic load test, following the loading protocol given by the ASTM Standard E2126-11. The dataset is composed of the forces and displacements read at the top section of the wall specimen. Finally, a nonlinear finite element model of the ferrocement wall, developed using SeismoStruct software, is also included along with the equivalent numerical simulation of the experimental test. This dataset can be potentially used for the calibration of hysteretic models with high pinching levels and the structural identification of ferrocement walls., (© 2024 The Authors.)