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In this paper, an experimental investigation addressed at the characterization of compressive strength of a weak units-strong mortar masonry is presented. This masonry, made with natural units of calcarenite improperly named “tufo”, is massively recurrent in the historic center of Matera, an UNESCO site since 1993. The tufo masonry was used for building ordinary and historical constructions, such as ancient churches and palaces, and nowadays it is extensively applied for restoration interventions in order to preserve the historic site and its surrounding area. At first, the research focuses on the evaluation of compressive strength of masonry components, by examining tufo cubic units and lime mortar prisms, and to propose relationships between non-destructive (sonic) and destructive (compression) tests statistically validated. Then, some formulations for estimating the masonry compressive strength by combining those of the basic masonry components are examined. Comparisons with results obtained with prism specimens (doublets and triplets) confirm that in this type of masonry compressive behavior (failure mode and compressive strength) is strictly dependent on tufo units. Finally, a probabilistic study of strength distribution highlights the importance of taking into account the compressive strength dispersion of each component, especially the one related to tufo units.

The electronic properties of hydrogenated, spherical, Si/Ge and Ge/Si core-shell nanocrystals with a diameter ranging from 1.8 to 4.0 nm are studied within Density Functional Theory. Effects induced by quantum confinement and strain on the near-band-edge states localization, as well as the band-offset properties between Si and Ge regions, are investigated in detail. On the one hand, we prove that Si(core)/Ge(shell) nanocrystals always show a type II band-offset alignment, with the HOMO mainly localized on the Ge shell region and the LUMO mainly localized on the Si core region. On the other hand, our results point out that a type II offset cannot be observed in small (diameter less than 3 nm) Ge(core)/Si(shell) nanocrystals. In these systems, quantum confinement and strain drive the near-band-edge states to be mainly localized on Ge atoms inducing a type I alignment. In larger Ge(core)/Si(shell) nanocrystals, instead, the formation of a type II offset can be engineered by playing with both core and shell thickness. The conditions that favor the transition from a type I to a type II alignment for Ge(core)/Si(shell) nanocrystals are discussed in detail., 12 pages, 7 figures

Folded regions are commonly encountered in a number of hexagonal boron nitride (h-BN) based bulk and nanostructured materials. Two types of structural modifications occur in folded h-BN layers: local curvature at the folded edges and interlayer shear of the layers which changes the stacking of the overlapping flat regions. In this work we discuss, via density functional theory simulations, the impact of these structural modifications on the ground state electronic structure of the pristine monolayer. We show that, depending on the fold orientation, the overlapping region might present different stacking configurations with subsequent variations of the fundamental band gap; further gap changes occur at the folded regions. The overall electronic structure of a BN folded monolayer can finally be described as a type-II junction between two wide gap semiconductors located at the curved and flat overlapping zones.

The objectives of this study were to examine the relation between clinical outcomes 1 year postoperatively, in a cohort of mechanically aligned total knee arthroplasties (TKA), and (1) the degrees of alignment change of the tibial, femoral and the hip–knee–ankle (HKA) angle; (2) the change of phenotype; (3) the postoperative knee joint line orientation to the floor. Pre-operative and postoperative long-leg X-rays of 90 patients were used to determine the coronal alignment. The absolute difference between the pre-operative and postoperative measurements was determined and the outcomes were categorized in whether or not a change in phenotype had occurred. Finally, the orientation of the knee joint line relative to the floor (tibial joint line angle—TJLA) was measured. Clinical outcomes were determined with the KOOS and KSS at 1-year follow-up. The clinical outcomes (1) did not correlate with the absolute difference of the alignment measured; (2) did not show a difference between patients with or without a change in phenotype; and (3) were higher (KOOS ADL, Sport and QoL) in patients with a medial open TJLA. This study showed no correlation between clinical outcomes and joint line restoration of the femur, tibia or HKA in patients after TKA. Leaving the prosthesis with some degrees of under correction on the coronal plane maintaining the phenotype, was not associated to better clinical results compared to TKA overcorrection. Nevertheless, the results showed that patients with a medial open TJLA had better clinical outcomes than patients with a lateral open TJLA. III.

In this study a seismic risk analysis of masonry buildings based on damage data of L’Aquila 2009 earthquake is presented. Typological loss curves and Expected Annualized Losses (EAL) values are pre...

In the scientific community there is an increasing attention to existing bridges. They usually suffer a marked structural deterioration due to a lack of maintenance although they belong to infrastructures serving an important amount of traffic. Therefore, there is the need of quickly evaluating the current state of these structures with the aim of promptly expressing a judgment about their usability. In this paper, the results of a fast appraisal method applied to a territorial case study are illustrated and commented in order to define a list of priority and the related additional investigations, including in situ tests and numerical analyses with more refined models. The paper concludes highlighting the importance of applying this decision tool in order to manage huge and important road infrastructures in conjunction with the interested traffic, and to plan more refined investigations within a multi-level evaluation framework.

Recovering and preserving ancient churches is necessary to ensure the transmission of this cultural heritage to the future generations. To this scope, it is necessary to evaluate their performance in seismic prone areas, to design interventions capable of reducing their vulnerability ensuring also their safety use for the faithful. In this paper, investigations on seismic performance of masonry churches are illustrated by applying two different numerical methods on a case study, an existing brick masonry church. The seismic assessment is conducted by applying two simplified methods proposed by the current Italian Directive containing the Guidelines for assessment and reduction of cultural heritage seismic risk. Moreover, linear kinematic analysis is used also for investigating the influence of main parameters governing to the main façade simple overturning and narthex longitudinal response. The investigations performed highlight that the activation multiplier of macro-element response mechanism may significantly vary according to the assumptions made and that also, as narthex longitudinal response, a minimization procedure of the activation multiplier is required.

We combine density functional theory and many body perturbation theory to investigate the electronic properties of Si(100) and Ge(100) surfaces terminated with halogen atoms (-I, -Br, -Cl, -F) and other chemical functionalizations (-H, -OH, -CH3) addressing the absolute values of their work function, electronic affinity and ionization potential. Our results point out that electronic properties of functionalized surfaces strongly depend on the chemisorbed species and much less on the surface crystal orientation. The presence of halogens at the surface always leads to an increment of the work function, ionization potential and electronic affinity with respect to fully hydrogenated surfaces. On the contrary, the presence of polar -OH and -CH3 groups at the surface leads to a reduction of the aforementioned quantities with respect to the H-terminated system. Starting from the work functions calculated for the Si and Ge passivated surfaces, we apply a simple model to estimate the properties of functionalized SiGe surfaces. The possibility of modulating the work function by changing the chemisorbed species and composition is predicted. The effects induced by different terminations on the band energy line-up profile of SiGe surfaces are then analyzed. Interestingly, our calculations predict a type-II band offset for the H-terminated systems and a type-I band offset for the other cases.

Background In total knee arthroplasty with patellar resurfacing, patellar bone preparation, component positioning and motion assessments are still not navigated. Only femoral/tibial component positioning is supported by computer-assistance. The aim of this study was to verify, in-vivo, whether knee surgical navigation extended to patellar resurfacing, by original instrumentation and procedures for patellar-based tracking, could achieve accurate patella preparation in terms of original thickness restoration, bone cut orientation, and normal knee motion. Methods An additional navigation system for patellar data acquisition was used together with a standard navigation system for total knee arthroplasty in 20 patients. This supported the surgeon for patellar resurfacing via measurement of removed bone thickness, three-dimensional patellar cut orientations, and patello-femoral motion. Radiological and clinical examinations at 6 and 24-month follow-up were also performed. Findings The medio-lateral patellar-bone cut orientation was respectively 0.5° (standard deviation: 3.0°) and 1.4° (1.7°) lateral tilt, as measured via navigation and post-operatively on the Merchant x-ray view. The cranio-caudal orientation was 3.8° (7.2°) of flexion. The thickness variation between patellar pre- and post-implantation was 0.2 (1.3) mm. Immediately after implantation, patello-femoral as well as tibio-femoral kinematics was within the normality. Good radiological and clinical examinations at 6 and 24-month follow-up were also observed. Interpretation For the first time, the effect of patellar navigation for its resurfacing was assessed in-vivo during surgery, with very good results for thickness restoration, proper cut orientation, and normal knee motion. These results support the introduction of patella-related navigation-based surgical procedures for computer-assisted total knee arthroplasty.

The article presents a preliminary assessment of seismic damage shown by 60 Mexican churches after the two earthquakes arisen in September 2017. The first earthquake occurred on September 7th and h...

Silicon germanium nanostructures (SiGe NSs) have acquired today a prominent role in several cutting-edge research topics in nanoscience, thanks to the most recent advances in synthesis, processing and characterization [1-4]. The physical properties of such nanosystems are strictly related not solely to the size of the system (as in pure Si and Ge NSs), but also to the relative composition of Si and Ge atoms as well as to the geometry of Si/Ge interface. The investigation of these materials with experimental techniques is, however, complicated by several factors not always well controlled which can hide the right comprehension of the fundamental properties. In this context first principles theoretical modeling is extraordinarily important as it can complement or augment experimental observations. Here, I will present an overview of the ab initio computational modeling of various types of SiGe nanosystems (nanowires [5], nanodots [6] and slabs [7-8]). I will outline how by bringing together two similar elements –Si and Ge, neighbors in the periodic table–, a broad variety of new chemical and physical properties emerge, stimulating both fundamental and application-driven research in nanoscience. Indeed, I will show that substituting some of the atoms of a pure Si NS with Ge in configurations of distinct compositions and dimensionalities, can strongly affect some fundamental properties such as band gap, band offsets, work function and impurity doping levels. Bibliography [1] M. Amato, M. Palummo, R. Rurali, S. Ossicini, Chem. Rev. 114, 1371 (2014) [2] I. Berbezier, A. Ronda, Surf. Sci. Rep., 64, 47 (2009) [3] J.-N Aqua, I. Berbezier, L. Favre, T. Frisch, A. Ronda, Phys. Rep., 522, 52 (2013) [4] D. J. Paul, Semicond. Sci. Technol. 19, R75–R108 (2004) [5] M. Amato, S. Ossicini and R. Rurali, Nano Lett. 11, 2, 594-598 (2011) [6] I. Marri, M. Amato, S. Ossicini, S. Grillo, O. Pulci, Interplay of quantum confinement and strain effects in type I to type II transition in Ge/Si core-shell nanocrystals (submitted, 2022) [7] I. Marri, M. Amato, M. Bertocchi, A. Ferretti, D. Varsano, S. Ossicini, Phys. Chem. Chem. Phys. 22, 25593-25605 (2020) [8] S. Pouch, M. Amato, M. Bertocchi, S. Ossicini, N. Chevalier, T. Mélin, J.M. Hartmann, O. Renault, V. Delaye, D. Mariolle, L. Borowik, J. Phys. Chem. C 119, 26776-26782 (2015)

In this paper two simplified methods are presented in order to assess the seismic performance of a set of Italian ancient churches. The methods applied are characterized by an increasing refinement level, requiring only some qualitative information in order to evaluate representative indexes of global seismic response. The methods considered may be applied for screening and identifying the current priorities at a territorial level and for planning, where necessary, more refined analysis for evaluating seismic response and required interventions (if necessary). Finally, applications to case studies are illustrated and compared with the aim of highlighting the limitations of the methods considered.

Eight historical mosques of Kermanshah constructed in 18th or 19th century CE are investigated with ambient vibration tests on their sites and buildings. Conventional peak picking technique is used for determination of structures’ fundamental frequencies and spectral ratio of horizontal to vertical components along with ellipticity inversion of Rayleigh waves are considered to identify the natural frequency of ground and shear wave velocity profile to define the site conditions according to the national codes of Iran and Italy. The recorded motions on the buildings are used to calculate the fundamental frequencies of the structure. Afterward, buildings are modeled by macro-element method and material properties are tuned in the way that the fundamental frequencies from the modal analyses match with the measured values from AVTs. Finally, more modal analyses are performed by the calibrated models to present an empirical relation between the natural period of the mosques, the geometrical characteristics of the buildings, and the mechanical properties of the construction materials. The results show that the natural periods of the masonry buildings of the mosques are different from the values of empirical relations in the national codes. Meanwhile, the proposed empirical relation presents the natural periods of the buildings of this study reasonably well and can be used for other masonry buildings of similar architecture and materials.

Background: In this research a rapid vulnerability and risk assessment at a territorial level is performed. Methods: The methodology used, initially proposed for ancient masonry churches, is extended and applied to ten historic masonry mosques in Kermanshah city. The method could be considered as preliminary risk assessment approach of historic structures, refers to LV0 method, since the used methodology requires simple qualitative information. It involves the application of three distinct tools; the exposure, the seismic hazard, and the seismic vulnerability. Results: The comparisons among the obtained results, by considering also the damages suffered during the last earthquakes and war blasts, validate the methodology proposed, capable of providing a seismic risk scoring at a territorial level also for ancient masonry mosques. As known, through this kind of approach, important information is obtained in order to manage and to mitigate the seismic risk of a certain territorial asset. The results show that all ten mosques has medium earthquake vulnerability condition. Emad e Doleh mosque is the most vulnerable case with vulnerability of 34. Navab mosque is located on the most hazardous place. Furthermore, the seismic vulnerability map and seismic risk indices are presented for all the investigated mosques. Conclusion: The obtained results are useful for ranking the priorities and for preliminary defining an interventions plan to be examined in detail with additional quantitative investigations carried out with more refined approaches.

Elastomeric bearings used as seismic isolation devices are key elements in the protection of constructions against earthquakes. They enable structures to exhibit very high performances when subject to extreme events, preventing damage both to structural and non-structural components. Their characteristics, however, are prone to change with time due to long term effects such as aging. Regular inspection and monitoring of their state are thus fundamental activities needed to ensure the required performances. The present work reviews the most common strategies adopted for such purpose, including visual inspections, Operational Modal Analysis (OMA), and quick release tests. An innovative characterisation method is also presented. Such method, with the use of a nanoindenter, enables testing of a small rubber sample (3 mm in diameter) cored from a device. Its suitability is confirmed through a comparison of the same device tested in a traditional setup.

Control and inspection of the conditions of elastomeric bearings used for seismic isolation purpose is a fundamental activity in ensuring and preserving the performance of a structure. The methods currently used, such as visual inspections, Operational Modal Analysis (OMA), release tests, very often present strong limitations due to their qualitative nature or else to the costs associated with their implementation and functioning. An innovative procedure based on the use of nanoindentation tests is proposed and validated through an experimental campaign. Its main benefits consist in the possibility of quantitatively estimating the current characteristics of elastomeric bearings, in conjunction with low implementation costs and influence on the isolating devices. The innovative procedure consists of coring a very small sample of rubber from a bearing and testing it with a nano-indenter in order to estimate the actual characteristics in terms of shear stress-strain relationships. The experimental tests showed good agreement between the properties calculated with the proposed method and the ones obtained directly through a traditional shear test, making such procedure a promising tool.

The objectives of this study were to examine the relation between clinical outcomes 1 year postoperatively, in a cohort of mechanically aligned total knee arthroplasties (TKA), and (1) the degrees of alignment change of the tibial, femoral and the hip-knee-ankle (HKA) angle; (2) the change of phenotype; (3) the postoperative knee joint line orientation to the floor.Pre-operative and postoperative long-leg X-rays of 90 patients were used to determine the coronal alignment. The absolute difference between the pre-operative and postoperative measurements was determined and the outcomes were categorized in whether or not a change in phenotype had occurred. Finally, the orientation of the knee joint line relative to the floor (tibial joint line angle-TJLA) was measured. Clinical outcomes were determined with the KOOS and KSS at 1-year follow-up.The clinical outcomes (1) did not correlate with the absolute difference of the alignment measured; (2) did not show a difference between patients with or without a change in phenotype; and (3) were higher (KOOS ADL, Sport and QoL) in patients with a medial open TJLA.This study showed no correlation between clinical outcomes and joint line restoration of the femur, tibia or HKA in patients after TKA. Leaving the prosthesis with some degrees of under correction on the coronal plane maintaining the phenotype, was not associated to better clinical results compared to TKA overcorrection. Nevertheless, the results showed that patients with a medial open TJLA had better clinical outcomes than patients with a lateral open TJLA.III.

Nowadays, Sonic Pulse Velocity tests (SPV tests) are widely applied for detecting the morphology, hidden defects, and voids within structural elements. This technique, largely applied because non i...

Nowadays, safety assessment under seismic loading of historical masonry buildings, such as ancient churches, is an actual and important topic due to the potential human and economic losses ...

Computer-assisted systems (CAS) for total knee arthroplasty (TKA) were expected to result in more accurate prosthesis implantation, better patient outcomes, and longer implant survival when compared to conventional instrumentation (CI). The aim of this study was to compare two groups of patients operated using CAS or CI at ten years follow-up. One hundred twenty TKA patients, 60 using CAS and 60 using CI, were contacted after a decade for follow-up. Eligible patients received radiological examination to assess the lower-limb mechanical axis. They were also clinically assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Knee Society Score for Knee (KSS-K) and Function (KSS-F) Scoring. Kaplan-Meier survival analysis was performed to assess revisions, not for post-traumatic reasons. In CAS and CI groups, the lower-limb mechanical axis was 1.7° ± 2.4° and 1.5° ± 2.8°, respectively; corresponding KOOS values were 82.3 ± 14.3 and 78.6 ± 14.4; KSS-K values were 85.9 ± 11.1 and 85.0 ± 9.7; KSS-F values were 82.2 ± 19.3 and 83.8 ± 18. For these assessments, the differences between the two groups were not statistically significant (p > 0.05). Two CAS (3.8%) and three CI patients (5.7%) were revised. The Kaplan-Meier analysis showed no significant differences between the two groups. No significant differences were found at long-term follow-up in terms of radiographical-clinical outcomes and of implant survival between TKA operated using CAS or CI.

Semiconducting nanowires (NWs) offer the unprecedented opportunity to host different crystal phases in a nanostructure, which enables the formation of polytypic heterostructures where the material composition is unchanged. This characteristic boosts the potential of polytypic heterostructured NWs for optoelectronic and phononic applications. In this work, we investigate cubic Ge NWs where small (∼20 nm) hexagonal domains are formed due to a strain-induced phase transformation. By combining a nondestructive optical technique (Raman spectroscopy) with density-functional theory (DFT) calculations, we assess the phonon properties of hexagonal Ge, determine the crystal phase variations along the NW axis, and, quite remarkably, reconstruct the relative orientation of the two polytypes. Moreover, we provide information on the electronic band alignment of the heterostructure at points of the Brillouin zone different from the one (Γ) where the direct band gap recombination in hexagonal Ge takes place. We demonstrate the versatility of Raman spectroscopy and show that it can be used to determine the main crystalline, phononic, and electronic properties of the most challenging type of heterostructure (a polytypic, nanoscale heterostructure with constant material composition). The general procedure that we establish can be applied to several types of heterostructures., I.Z. acknowledges financial support from the Swiss National Science Foundation research grant (Project Grant No. 200021_165784). C.F. acknowledges financial support from Sapienza University scholarship “Borsa di Perfezionamento all’Estero 2017–2018”. R.R. acknowledges financial support by the Ministerio de Economia, Industria y Competitividad (MINECO) under grant FEDER-MAT2017-90024-P and the Severo Ochoa Centres of Excellence Program under Grant SEV-2015-0496 and by the Generalitat de Catalunya under grants no. 2017 SGR 1506. L.V. acknowledges financial support from the IDEX Paris-Saclay (ANR-11-IDEX-0003-02). This work was partly supported by the ANR HEXSIGE project (ANR-17-CE030-0014-01) of the French Agence Nationale de la Recherche. R.R. and M.A. thank Giacomo Giorgi and Thanayut Kaewmaraya for useful discussions.

Introduction: Existing old masonry arch bridges represent an architectural and cultural heritage of inestimable value because most of them were built in the last century and are still in service. They represent a very important part of roads and railways networks, having also an important strategic role. They are actually serving roads characterized by transit loads definitively heavier and more frequent than the ones of the past. Moreover, very often maintenance absence and material worn away, increased by the way by the environmental conditions, accelerate more and more the elements deterioration with a consequent loss of integrity and reduction of their carrying capacity. Methods: In this paper the seismic assessment of an old multi span masonry arch bridge still in service is evaluated. The bridge, located in Southern Italy, was built before the Second World War and crosses the “Cavone” River, from which it takes the name. Results and Conclusion: A series of numerical analyses are performed in order to evaluate its seismic performance and the model sensitivity with respect to the assumed masonry mechanical properties.

This prospective study was undertaken to evaluate the diagnostic accuracy of the Synovasure™ α-defensin lateral flow assay to detect or exclude infection and to compare it to the sensitivity and specificity of other diagnostic criteria according to the International Consensus Group on Periprosthetic Joint Infection (PJI). All patients who have undergone revision total knee arthroplasty (TKA) from September 2015 to July 2016 were included: 16 chronic (more than 3 months after performing arthroplasty) infections and 35 aseptic joints were identified. The diagnostic performance of single test was assessed by receiver operating characteristic (ROC) curve analyses. The sensitivity and specificity were calculated for each of the cut-off values and the area under the curve (AUC) was also calculated. The median synovial fluid (SF) leukocyte count, as well as the neutrophil percentage, was significantly higher in patients with PJI than in those with aseptic failure (p

In this paper, an analytical model of confined concrete proposed for square sections is extended to the case of rectangular ones. The new and generalized formulation, based on the elasticity theory, is developed under the key assumption that the confinement arises in plane-strain conditions. The proposed model provides, through the analogy among the section core and internal cylinders, the confining pressure in polar coordinates to be applied for computing the actual concrete curve subjected to passive confinement. In this procedure, as for the square confined sections, any active confinement model derived from triaxial tests on cylindrical specimens may be involved. The extended model is also suitable for evaluating the confining pressure offered by additional external strengthenings in any material, such as for example FRP wraps and/or steel jackets. Comparisons among numerical simulations and experimental data demonstrate the accuracy of the new generalized analytical model in predicting the confined stress-strain relationship of concrete in the case of either newly designed or old existing concrete elements, also when multiple transverse reinforcements are applied.

Estimating the saftey of an ancient masonry arch bridge is a legitimate, but very interesting, structural engineering challenge. This is due to the fact that most of these bridges are still in service and suffer from higher and more frequent cyclic loads, a problem not encountered in the past. Therefore, for these structures it is important to know the actual fatigue strength rather than the ultimate carrying capacity in order to provide useful indications on the remaining service life with also possible traffic load limitations.In this article, different models are applied according to the stress-life curve method for estimating the fatigue strength of a case study: an ancient multi-span masonry arch bridge still in service. The obtained results highlight that, unlike steel elements, current design codes do not provide any relevant indication as to the fatigue strength assessment of existing masonry membratures. Moreover, appropriate stress-life curves are needed for evaluating the actual capacit...

Recent advances in the fabrication of group IV homojunctions made by cubic-diamond (3C) and hexagonal-diamond (2H) phases call for a detailed understanding of the physics underlying their electronic structure. In this work, we employ hybrid density functional theory (hybrid-DFT) calculations to study the structural and electronic properties of Si and Ge polytype junctions. Starting from high-resolution transmission electron microscopy (HRTEM) micrographs of 2H/3C Si nanowires, we build a computational model that takes into account both crystal-phase effects and the length of the junction. We obtain accurate estimations of the magnitudes of the band offsets: In particular, we show that 2H/3C Si interfaces induce a type-II band alignment, whereas the Ge structures exhibit a type-I band offset. Furthermore, both Si and Ge homojunctions have direct gaps that are smaller than those of the bulk 3C phase. Finally, we demonstrate that, in all of the considered systems, varying the thickness of the hexagonal phase...

We report the observation of an intense anomalous peak at 1608 cm$^{-1}$ in the Raman spectrum of graphene associated to the presence of chromium nanoparticles in contact with graphene. Bombardment with an electron beam demonstrates that this peak is distinct from the well studied D$'$ peak appearing as defects are created in graphene; the new peak is found non dispersive. We argue that the bonding of chromium atoms with carbon atoms softens the out-of-plane optical (ZO) phonon mode, in such a way that the frequency of its overtone decreases to $2\omega_{\rm ZO}\sim\omega_{\rm G}$, where $\omega_{\rm G}$=1585~cm$^{-1}$ is the frequency of the Raman-active E$_{\rm 2g}$ mode. Thus, the observed new peak is attributed to the 2ZO mode which becomes Raman-active following a mechanism known as Fermi resonance. First-principles calculations on vibrational and anharmonic properties of the graphene/Cr interface support this scenario., Comment: 12 pages, 10 figures

Nowadays, seismic retrofit through isolation strategy represents a consolidated technique of protection against design earthquakes. This technique is also applied on existing structures extensively, due to the fact that it usually does not require any interruption of the building use and occupants evacuation. If applicable, it rapidly allows the seismically retrofitting of a building installed with seismic devices with low horizontal stiffness between the structure and the foundation decoupling, in fact, this allows the motion of the superstructure from the ground one. In this paper an application on an existing RC building of the seismic isolation is presented. The chosen building was built in the ‘90s only for vertical loads and realized without any detailing rule for structural ductility. The seismic retrofitting requirement stems from the fact that only recently, after the National seismic hazard maps update in 2003, the considered area has been upgraded to a medium-low seismic intensity zone, while at construction time no seismic classification was in existence by law. The case study peculiarity is that the seismic retrofitting has required an addition to seismic devices at the base, with related interventions such as the application of a bracing system consisting of two elastic steel frames. This intervention is required for stiffening the superstructure and, therefore, minimizing the higher vibration modes effects. The paper presents the main results obtained with a FEM model, implemented for simulating the initial and the design state when the interventions are considered. Finally, some results of non-linear dynamic time-history analyses are illustrated and commented for verifying superstructure elements and seismic devices.