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Il danneggiamento sismico di componenti non-strutturali in caso di evento sismico può com-portare l’interruzione di funzionalità degli edifici interessati e perdite economiche notevoli. Tra i componenti non-strutturali, i sistemi costituiti da partizioni e controsoffitti rappresentano un investimento significativo nel settore delle costruzioni. Tuttavia, la questione dell’adeguata progettazione sismica di tali sistemi riveste ancora un ruolo di secondaria importanza nell’ambito della progettazione strutturale, riflettendosi in notevoli carenze normative. Poiché il comportamento di tali sistemi non può essere facilmente simulato tramite i tradizionali me-todi di analisi, la caratterizzazione sperimentale può rappresentare l’unica procedura efficace. In questo scenario si inquadra la collaborazione tra la KnaufGips KG e l’Università di Napoli “Federico II”, finalizzata alla conoscenza della risposta sismica di sistemi non-strutturali light-weight steel, ossia di partizioni e controsoffitti continui realizzati con profili cold-formed e rivestiti con pannelli in cartongesso. La presente memoria illustra e discute nello specifico le prove monotone quasi-statiche e le prove di identificazione dinamica fuori piano condotte su pareti di partizione, illustrandone i principali risultati ottenuti.

Past earthquakes have shown that the damage to non-structural elements can severely limit the functionality of most affected buildings and cause substantial economic losses compared to structural damage. Among the non-structural components, the ceiling-partition systems represent a significant investment in construction sector. Nevertheless, their seismic performance is poorly understood, because information and specific guidance are very limited. Since the behaviour of these systems cannot be easily simulated with traditional structural analysis, seismic design by testing is an effective procedure. For these reasons, an experimental campaign has been planned at the University of Naples Federico II with the main aim to characterize the seismic response of different Knauf partition walls and suspended continuous plasterboard ceilings. This paper presents and discusses an experimental campaign involving out-of-plane quasi-static monotonic tests and step-relaxation tests on partition walls, mainly devoted to develop out-of-plane seismic design by testing of Knauf drywall partitions.

The European project named "Energy Efficient LIghtweight-Sustainable-SAfe-Steel Construction" (Project acronym: ELISSA) is devoted to the development and demonstration of cold-formed steel (CFS) modular systems. In particular, these systems are nano-enhanced prefabricated lightweight steel skeleton/dry wall construction with improved thermal, vibration/seismic and fire performance, resulting from the inherent thermal, damping and fire spread prevention properties. From a structural point of view, these systems are represented by a sheathed-braced CFS solution, in which the seismic resistant elements are made of “Cocoon” CFS stud shear walls laterally braced by “Knauf” gypsum-based panels. The project plans the research activities on the basis of three levels: micro-scale, meso-scale and macro-scale. Concerning the research activity for the seismic performance evaluation, these three levels correspond to different test typologies. In particular, the micro-scale level consists of tests on materials/products/components forming the seismic resistant elements (shear walls), the meso-scale level corresponds to tests on single walls, the macro-scale level consists of shaking table tests on full scale two stories house prototype. This paper presents and discusses the planning of the research given information about test programs, specimens/prototypes, instrumentations and loading protocols.

The Cold-Formed Steel (CFS) structures are able to ensure a good structural response in seismic areas. Among them, the stick-built constructions raise a considerable interest in recent studies. In these structures, the lateral load bearing systems are CFS stud walls, that are generally realized with a frame in CFS profiles that can be braced by light gauge steel straps installed in an X configuration. In this case, the "all steel" design methodology can be adopted and the lateral resisting system is assured by the CFS strap-braced stud walls.

The search for innovative building methods to ensure high structural, technological and environmental performance is promoting the development of light gauge steel structural systems. Among them, stick-built constructions realized with Cold-Formed Steel (CFS) profiles are attracting considerable interest in the construction sector and in the recent research studies. Nevertheless, the main European structural code for seismic design, the Eurocode 8 part 1 (EN 1998-1) [1], does not provide any prescription for the seismic design of CFS structures. Presently, the "North American Standard for Cold Formed Steel Framing - Lateral Design" AISI S213-07 [2] represents the only reference for the design of this structural typology under seismic actions. This document is developed by the American Iron and Steel Institute Committee on Framing Standards and it codifies the design of different seismic resistant CFS systems for Canada, Mexico and United States. As an effort to define the seismic design criteria for such structures, an extended theoretical and experimental study aimed to investigate the seismic behaviour of strap-braced stud shear walls has been carried out within RELUIS –DPC 2010-2013 research project. The research included a wide experimental campaign as well as theoretical analyses to define criteria for the seismic design of strap braced CFS structures. Among the different steel seismic-resistant systems regulated by the EN 1998-1, traditional concentrically braced frame (X diagonal) represents the closest system to the investigated one. In this paper a critical analysis of the current standards is illustrated, with particular reference to the analysis and comparison of the existing provisions for the two similar structural typologies (traditional concentrically braced frames and strap braced CFS system). Based on the results of that critical analysis, the design hypotheses for the definition of a case study have been defined. In addition, on the basis of the adopted design assumptions and the experimental results [3], guidelines for the seismic design of strap braced CFS structures are proposed.

Past earthquakes have shown that the damage to non-structural elements can severely limit the functionality of most affected buildings and cause substantial economic losses. Among the non-structural building components, the ceiling-partition systems represent a large economic investment in construction sector. Nevertheless, their seismic performance is poorly understood, because information and specific guidance are very limited. In the last years, international studies have been conducted on the seismic behaviour of light gage steel stud partition walls (Lee et al. [1], Restrepo and Bersofsky [2], Tasligedik et al. [3], Retamales et al. [4], Magliulo at al. [5]), suspended ceilings (Badillo et al. [6], Magliulo et al. [7], Gilani et al. [8], Soroushian et al. [9],) and partition walls - ceiling systems (Filiatrault et al. [10], McCormick at al. [11]). Since the behaviour of these systems cannot be easily simulated with traditional structural analysis, experimentation is the main way to assess the seismic response. For these reasons, an experimental campaign has been planned at the University of Naples Federico II with the main aim to characterize the seismic response of different Cold-Formed Steel (CFS) partition drywalls and suspended continuous plasterboard ceilings. The current paper presents the research project, in terms of experimental program, prototypes and specifically designed set-up.

Retrofit of unreinforced masonry (URM) structures is incessantly attracting interests of masonry professionals. Because there are enormous URM structure stocks in different parts of the world that have shown vulnerability to damage against out-of-plane actions due to having limited flexural strength and deformation capacity [1]. As such, there is a global trend of promoting the development of sustainable retrofit techniques for URM structures. The authors' previous study [2] has introduced the application of oriented strand board type 3 (OSB/3) as a prospective sustainable retrofit material for URM wall with evidence of improving the flexural performances. This paper presents, for the first time,experimental works on 1115 x 1115 x 215 mm double wythe single leaf URM walls. Specifically, quasi-static out-of-plane loading tests were carried out on two plain specimens, two single-sided retrofitted walls and two double-sided retrofitted walls. The flexural and displacement capacities were evaluated in both plain and retrofitted specimens, and the results substantiated that OSB/3 application improves the flexural capacity of masonry wall. Therefore, the application of OSB/3 for retrofitting URM buildings can be considered as an inexpensive, efficient and sustainable retrofit technique.

Background. Cardiac masses (CM) represent a heterogeneous clinical scenario, and sex-related differences of these patients remain to be established. Purpose: To evaluate sex-related disparities in CMs regarding clinical presentation and outcomes. Material and Methods. The study cohort included 321 consecutive patients with CM enrolled in our Centre between 2004 and 2022. A definitive diagnosis was achieved by histological examination or, in the case of cardiac thrombi, with radiological evidence of thrombus resolution after anticoagulant treatment. All-cause mortality at follow-up was evaluated. Multivariable regression analysis assessed the potential prognostic disparities between men and women. Results. Out of 321 patients with CM, 172 (54%) were female. Women were more frequently younger (p = 0.02) than men. Regarding CM histotypes, females were affected by benign masses more frequently (with cardiac myxoma above all), while metastatic tumours were more common in men (p < 0.001). At presentation, peripheral embolism occurred predominantly in women (p = 0.03). Echocardiographic features such as greater dimension, irregular margin, infiltration, sessile mass and immobility were far more common in men. Despite a better overall survival in women, no sex-related differences were observed in the prognosis of benign or malignant masses. In fact, in multivariate analyses, sex was not independently associated with all-cause death. Conversely, age, smoking habit, malignant tumours and peripheral embolism were independent predictors of mortality. Conclusions. In a large cohort of cardiac masses, a significant sex-related difference in histotype prevalence was found: Benign CMs affected female patients more frequently, while malignant tumours affected predominantly men. Despite better overall survival in women, sex did not influence prognosis in benign and malignant masses.

Lightweight steel (LWS) buildings, made of cold-formed steel (CFS) systems, have many advantages and are often employed in seismic areas as low- and medium rise buildings. However, in Europe the codification does not provide specific rules for seismic design of those structures. In light of this, the University of Naples “Federico II” has recently completed a research project in cooperation with Lamieredil S.p.A. Italian Company, aimed to investigate the seismic behaviour of non-dissipative strap-braced structures. The partnership between academia and industry also led to development of a patented system. This paper discusses the selection and design process of the case study buildings and the overall experimental activity, going from small-scale tests of components, to static tests of full-scale walls, up to shake-table tests of two reduced scale mock-ups, which differ only for the adopted floor typology. The influence of floor typology on the seismic response of CFS strap-braced structures is also provided. Tests results confirmed that, although no specific seismic rules were employed, strap-braced structures had a good seismic response achieving high inter-storey drifts without showing severe damages.