20 results on '"Petracca, Massimo"'
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2. Local infill-frame interaction under seismic loads: Investigation through refined micro-modeling
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Di Trapani, Fabio, Di Benedetto, Marilisa, Petracca, Massimo, and Camata, Guido
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- 2024
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3. Micro-modelling of stone masonry template buildings as a strategy for seismic risk assessment in developing countries
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Cross, Theodore, De Luca, Flavia, De Risi, Raffaele, Camata, Guido, and Petracca, Massimo
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- 2023
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4. Evaluation of the additional shear demand due to frame-infill interaction: a new capacity model
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Trapani, Fabio Di, Bogatkina, Valentina, Petracca, Massimo, and Camata, Guido
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- 2023
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5. Modelling the nonlinear static response of a 2-storey URM benchmark case study: comparison among different modelling strategies using two- and three-dimensional elements
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Cannizzaro, Francesco, Castellazzi, Giovanni, Grillanda, Nicola, Pantò, Bartolomeo, and Petracca, Massimo
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- 2022
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6. Nonlinear modelling of the seismic response of masonry structures: Calibration strategies
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D’Altri, Antonio Maria, Cannizzaro, Francesco, Petracca, Massimo, and Talledo, Diego Alejandro
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- 2022
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7. Validation of non-linear equivalent-frame models for irregular masonry walls
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Camata, Guido, Marano, Corrado, Sepe, Vincenzo, Spacone, Enrico, Siano, Rossella, Petracca, Massimo, Roca, Pere, and Pelà, Luca
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- 2022
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8. Adaptive and off-line techniques for non-linear multiscale analysis
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Zaghi, Stefano, Martinez, Xavier, Rossi, Riccardo, and Petracca, Massimo
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- 2018
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9. Numerical investigation of non-linear equivalent-frame models for regular masonry walls
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Siano, Rossella, Roca, Pere, Camata, Guido, Pelà, Luca, Sepe, Vincenzo, Spacone, Enrico, and Petracca, Massimo
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- 2018
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10. Multiscale computational first order homogenization of thick shells for the analysis of out-of-plane loaded masonry walls
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Petracca, Massimo, Pelà, Luca, Rossi, Riccardo, Oller, Sergio, Camata, Guido, and Spacone, Enrico
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- 2017
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11. Unsupervised Deep Learning for Structural Health Monitoring.
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Boccagna, Roberto, Bottini, Maurizio, Petracca, Massimo, Amelio, Alessia, and Camata, Guido
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STRUCTURAL health monitoring ,DEEP learning ,MACHINE learning ,CIVIL engineering ,SENSOR placement - Abstract
In the last few decades, structural health monitoring has gained relevance in the context of civil engineering, and much effort has been made to automate the process of data acquisition and analysis through the use of data-driven methods. Currently, the main issues arising in automated monitoring processing regard the establishment of a robust approach that covers all intermediate steps from data acquisition to output production and interpretation. To overcome this limitation, we introduce a dedicated artificial-intelligence-based monitoring approach for the assessment of the health conditions of structures in near-real time. The proposed approach is based on the construction of an unsupervised deep learning algorithm, with the aim of establishing a reliable method of anomaly detection for data acquired from sensors positioned on buildings. After preprocessing, the data are fed into various types of artificial neural network autoencoders, which are trained to produce outputs as close as possible to the inputs. We tested the proposed approach on data generated from an OpenSees numerical model of a railway bridge and data acquired from physical sensors positioned on the Historical Tower of Ravenna (Italy). The results show that the approach actually flags the data produced when damage scenarios are activated in the OpenSees model as coming from a damaged structure. The proposed method is also able to reliably detect anomalous structural behaviors of the tower, preventing critical scenarios. Compared to other state-of-the-art methods for anomaly detection, the proposed approach shows very promising results. [ABSTRACT FROM AUTHOR]
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- 2023
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12. Regularization of first order computational homogenization for multiscale analysis of masonry structures
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Petracca, Massimo, Pelà, Luca, Rossi, Riccardo, Oller, Sergio, Camata, Guido, and Spacone, Enrico
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- 2016
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13. Micro-scale continuous and discrete numerical models for nonlinear analysis of masonry shear walls
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Petracca, Massimo, Pela, Luca, Rossi, Riccardo, Zaghi, Stefano, Camata, Guido, and Spacone, Enrico
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Masonry -- Analysis ,Shear walls -- Methods ,Computer simulation -- Analysis -- Usage ,Business ,Construction and materials industries - Abstract
ABSTRACT A novel damage mechanics-based continuous micro-model for the analysis of masonry-walls is presented and compared with other two well-known discrete micro-models. The discrete micro-models discretize masonry micro-structure with nonlinear [...]
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- 2017
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14. Digital Twin: a Hybrid Approach for Structural Health Monitoring
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Amelio, Alessia, Boccagna, Roberto, Bottini, Maurizio, Camata, Guido, Germano, Nicola, Petracca, Massimo, and Amelio, Alessia
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[INFO.INFO-AI] Computer Science [cs]/Artificial Intelligence [cs.AI] ,[SPI.GCIV] Engineering Sciences [physics]/Civil Engineering ,[STAT] Statistics [stat] - Abstract
The scope of this work is to illustrate the advantages that can be obtained in the context of structural health monitoring (SHM) when data-driven and model-based approaches are combined through the construction of a numerical twin of the structure. While the strategy isn't entirely novel per se, the use of wholly integrated technologies and software developed by the same company for all parts of the workflow, preventing data loss and ensuring interoperability, is where the originality lies. ASDEA S.r.l. provides products designed to perform each part in the SHM cycle, spanning from data acquisition to alert emission and damage management. The paper describes how the pieces are put together inside the coherent environment provided by the STKO software, initially designed as a powerful interface to the OpenSees solver for finite element methods (FEM). Data is acquired through a network of MonStr sensors (produced by ASDEA Hardware), managed using artificial intelligence (AI). The data is then exposed to near-real-time analysis to obtain an accurate picture of the structural conditions, and the numerical model is updated continuously to reflect present conditions. When anomalies are detected by the AI-based classifier, they are compared to the output provided by the FEM analysis to ensure reliability.
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- 2022
15. Advanced tools for fast micro-modelling of masonry structures
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Petracca, Massimo, Marano, Corrado, Camata, Guido, Pelà, Luca|||0000-0001-7760-8290, Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental, and Universitat Politècnica de Catalunya. ATEM - Anàlisi i Tecnologia d'Estructures i Materials
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Continuum damage ,Construccions de maó ,IMPLEX ,Enginyeria civil::Materials i estructures [Àrees temàtiques de la UPC] ,Masonry--Mathematical models ,Masonry ,Micro-modelling - Abstract
Among all the approaches commonly used to study masonry structures, micro-modelling is the most accurate. Masonry can be seen as a composite material made of bricks and mortar joints. Their different mechanical properties, their geometry and their arrangement inside the micro-structure, lead to very complex behaviours that are often difficult to represent using equivalent homogenous constitutive models commonly available in commercial and research FEM solvers. Micro-modelling can capture the complex non-linear behaviours of masonry by explicitly modelling the micro-structure inside the computational model. Micro-modelling leads to models with a large number of finite elements, thus increasing prohibitively the computational time. This is also due to the problem of solving complex nonlinear solutions involving damage and strain localization, leading to very small time-steps required to achieve convergence. Another issue with micro-modelling is the increased complexity in generating the finite element mesh with all the details of the micro-structure. This work presents some advanced tools that can decrease the high computational time required by micro-modelling. A 2-parameter tension-compression plastic-damage constitutive model is presented as an extension of an existing model previously formulated by some of the authors [1,2,3]. The model is implemented in the open-source FEM code OpenSEES [12] with the IMPL-EX method [5], a mixed implicit-explicit integration method that renders the response of this constitutive model step-wise linear, thus removing the convergence issues typically encountered when dealing with softening responses. This research also presents a tool implemented in the STKO (Scientific ToolKit for OpenSees) pre- and post-processor [4] able to automatically convert a homogeneous CAD geometry of a building into a micro-model. Objectius de Desenvolupament Sostenible::13 - Acció per al Clima Objectius de Desenvolupament Sostenible::13 - Acció per al Clima::13.1 - Enfortir la resiliència i la capacitat d’adaptació als riscos relacionats amb el clima i els desastres naturals a tots els països Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles::11.4 - Redoblar els esforços per a protegir i salvaguardar el patrimoni cultural i natural del món
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- 2021
16. Nonlinear modelling of the seismic response of masonry structures: Calibration strategies.
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D'Altri, Antonio Maria, Cannizzaro, Francesco, Petracca, Massimo, and Talledo, Diego Alejandro
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SEISMIC response ,MASONRY ,CALIBRATION ,AXIAL loads ,MECHANICAL models ,NONLINEAR analysis - Abstract
In this paper, a simple and practitioners-friendly calibration strategy to consistently link target panel-scale mechanical properties (that can be found in national standards) to model material-scale mechanical properties is presented. Simple masonry panel geometries, with various boundary conditions, are utilized to test numerical models and calibrate their mechanical properties. The calibration is successfully conducted through five different numerical models (most of them available in commercial software packages) suitable for nonlinear modelling of masonry structures, using nonlinear static analyses. Firstly, the panel stiffness calibration is performed, focusing the attention to the shear stiffness. Secondly, the panel strength calibration is conducted for several axial load ratios by attempts using as reference the target panel strength deduced by well-known analytical strength criteria. The results in terms of panel strength for the five different models show that this calibration strategy appears effective in obtaining model properties coherent with Italian National Standard and Eurocode. Open issues remain for the calibration of the post-peak response of masonry panels, which still appears highly conventional in the standards. [ABSTRACT FROM AUTHOR]
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- 2022
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17. Tension-Compression Damage Model with IMPL-EX Algorithm for Micromodeling of Masonry Structures
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Berto, Luisa, Camata, Guido, Petracca, Massimo, Saetta, Anna, and Talledo, Diego
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Continuum damage model ,IMPL-EX ,Masonry ,Micro-modelling ,STKO - Published
- 2019
18. Automatic Calibration of Constitutive Models in STKO Pre-Processor
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Berto, Luisa, Camata, Guido, Petracca, Massimo, Saetta, Anna, and Talledo, Diego
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Automatic calibration ,Concrete constitutive models ,STKO ,Confinement ,Damage model ,Pre-processing - Published
- 2019
19. Seismic Interaction of Adjacent Structures on Liquefiable Soils: Insight from Centrifuge and Numerical Modeling.
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Hwang, Yu-Wei, Ramirez, Jenny, Dashti, Shideh, Kirkwood, Peter, Liel, Abbie, Camata, Guido, and Petracca, Massimo
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CENTRIFUGES ,SOIL structure ,STRUCTURED financial settlements ,SETTLEMENT of structures ,NONLINEAR analysis - Abstract
In urban environments, structures are often built in close proximity to each other. Seismic coupling and structure-soil-structure interaction (SSSI) are known to affect system accelerations, settlement, and tilt with consequential impact on structural damage. Yet, the extent and nature of these interactions are poorly understood, particularly on ground susceptible to liquefaction. In this paper, we use dynamic centrifuge and numerical modeling of isolated and neighboring, similar and dissimilar, shallow-founded structures on layered, level, saturated, and liquefiable soils to provide insight into (1) the mechanisms of SSSI; and (2) the relative influence of key parameters on system performance. Fully-coupled, nonlinear finite-element analyses of the centrifuge experiments indicated that in addition to a comprehensive calibration of the soil constitutive model parameters, use of higher-order elements and a sufficiently large domain size in three dimensions (3D) were critical ingredients to predicting the general trends in system response compared to centrifuge recordings. A limited numerical sensitivity analysis was performed subsequently. The results identified the key parameters affecting SSSI as spacing between the two foundations (S) in relation to their width (W) as well as the contact stress and geometry of the neighboring foundation-structure system. SSSI slightly decreased the permanent settlement of structures at the expense of a notable increase in their permanent tilt, particularly when S≤W. The foundation's spectral accelerations were observed to amplify at shorter periods when near a taller and heavier building at S≤W/3 , which was attributed to the added confinement. Increasing the uniform thickness of the critical liquefiable layer increased both adjacent structures' permanent settlement, while not affecting their residual tilt or SSSI. Importantly, the impact of SSSI on foundation tilt and accelerations remained significant for building spacings exceeding 2.5W. The results point to the importance of considering the impact of SSSI on structure's key engineering demand parameters and the urgent need for improved guidelines when assessing and treating liquefaction in urban settings. [ABSTRACT FROM AUTHOR]
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- 2021
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20. Computational multiscale analysis of masonry structures
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Petracca, Massimo, Universitat Politècnica de Catalunya. Departament d'Enginyeria Civil i Ambiental, Università degli Studi G.D'Annunzio, Pelà, Luca, Camata, Guido, and Rossi, Riccardo
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Enginyeria civil [Àrees temàtiques de la UPC] ,Construcció en maó ,Resistència de materials - Abstract
Masonry is an ancient building material that has been used throughout the history, and it is still used nowadays. Masonry constitutes the main building technique adopted in historical constructions, and a deep understanding of its behavior is of primary importance for the preservation of our cultural heritage. Despite its extensive usage, masonry has always been used following a trial and error approach and rules-of-thumb, due to a poor understanding of the complex mechanical behavior of such a composite material. Advanced numerical methods are therefore attractive tools to understand and predict the behavior of masonry up to and including its complete failure, allowing to estimate the residual strength and safety of structures. Several numerical methods have been proposed in recent years, either based on a full micro-modeling of masonry constituents, or on phenomenological macro models. In-between these two approaches, computational homogenization techniques have recently emerged as a promising tool joining their advantages. The problem is split into two scales: the structural scale is treated as an equivalent homogeneous medium, while the complex behavior of the heterogeneous micro-structure is taken into account solving a micro-scale problem on a representative sample of the micro-structure. The aim of this research is the development of a computational multiscale homogenization technique for the analysis of masonry structure, subjected to quasi-static in-plane and out-of-plane loadings. Classical Cauchy continuum theory is used at both scales, thus using the so-called first order computational homogenization. Due to the brittle nature of masonry constituents, particular attention is given to the problem of strain localization. In this context, the present research proposes an extension of the fracture-energy-based regularization to the two-scale homogenization problem, allowing the use of first order computational homogenization in problems involving strain localization. The method is first stated for the standard continuum case, and it is applied to the two-dimensional analysis of in-plane loaded shear walls made of periodic brick masonry. Then, the aforementioned method is extended to the case of shell structures for the analysis of out-of-plane loaded masonry walls. For this purpose, a novel homogenization technique based on thick shell theory is developed. Both in the in-plane and in the out-of-plane loading conditions, the accuracy of the proposed method is validated comparing it with experimental evidences and with micro-model analyses. The regularization properties are also assessed. The obtained results show how computational homogenization is an ideal tool for an accurate evaluation of the structural response of masonry structures, accounting for the complex behavior of its micro-structure., La obra de fábrica es un material de construcción tradicional que ha sido utilizado a lo largo de la historia y que sigue siendo utilizado hoy en día. La obra de fábrica constituye la principal técnica de construcción adoptada en estructuras históricas, y una comprensión profunda de su comportamiento es de vital importancia para la conservación de nuestro patrimonio cultural. A pesar de su amplio uso, la obra de fábrica ha sido utilizada frecuentemente adoptando un enfoque empírico, debido a un escaso conocimiento del comportamiento mecánico complejo de este tipo de material compuesto. Los métodos numéricos avanzados son herramientas atractivas para entender y predecir el comportamiento de la obra de fábrica hasta su fallo, permitiendo estimar la resistencia residual y la seguridad de las estructuras. Durante los últimos años, han sido propuestos diferentes modelos computacionales, basados bien en una micro-modelización completa de los constituyentes del material (ladrillos y juntas de mortero), o bien en macro-modelos fenomenológicos. A partir de estos dos enfoques, los métodos de homogenización computacional han emergido recientemente como una herramienta prometedora que puede combinar las ventajas de la micro- y macro-modelización. El problema se divide en dos pasos: la escala estructural se trata como un medio homogéneo equivalente, mientras el comportamiento complejo de la microestructura heterogénea se tiene en cuenta mediante la resolución de un problema micro-mecánico reconducible a una muestra representativa de la microestructura. El objetivo de esta investigación es el desarrollo de una técnica de homogenización computacional multi-escala para el análisis de estructuras de obra de fábrica sometidas a cargas horizontales cuasi-estáticas que actúan en el plano y fuera del plano. Se adopta la teoría clásica del medio continuo de Cauchy en ambas las escalas, utilizando así la homogeneización computacional del primer orden. Debido a la naturaleza frágil de los componentes de la obra de fábrica, el estudio contempla también el problema de la localización de la deformación en el marco del enfoque numérico de fisura distribuida. En este contexto, la presente investigación propone una extensión de la regularización basada en la energía de fractura para el problema de homogenización en dos escalas, permitiendo el uso de la homogenización computacional del primer orden en problemas que implican la localización de la deformación. El método se plantea en primer lugar para el caso continuo general, y a continuación se aplica al análisis de muros de corte cargados en su plano y hechos de fábrica de ladrillos con aparejo periódico. Posteriormente, el método se extiende al caso de estructuras tipo placa para el análisis de muros de obra de fábrica cargados fuera de su plano. Para este propósito, se desarrolla una nueva técnica de homogenización basada en la teoría de placas gruesas. En ambos los casos de carga en el plano y fuera del plano, la precisión del método propuesto se valida mediante la comparación con ensayos experimentales y análisis de micro-modelización. También se validan las propiedades de regularización. Los resultados obtenidos muestran cómo la homogeneización computacional pueda resultar una herramienta válida para una evaluación precisa de la respuesta estructural de las estructuras de obra de fábrica, teniendo en cuenta el comportamiento complejo de la micro-estructura., La muratura è un antico materiale da costruzione che è stato utilizzato in special modo nel corso della storia, ma che è ancora oggi piuttosto diffuso. La muratura è la tecnica principale di costruzione adottata in edifici storici, e una profonda comprensione del suo comportamento è di vitale importanza per la conservazione del nostro patrimonio culturale. Nonostante il suo ampio utilizzo, la muratura è sempre stata utilizzata seguendo un approccio empirico, a causa di una scarsa comprensione del complesso comportamento meccanico di tale materiale composito. I metodi numerici avanzati sono, quindi, strumenti attraenti per studiare e comprendere il comportamento della muratura fino al suo collasso, permettendo di stimare la resistenza residua e la sicurezza delle strutture. Diversi metodi numerici sono stati proposti negli ultimi anni, basati o sulla completa micro-modellazione dei componenti della muratura (mattoni e giunti di malta), o su macro-modelli fenomenologici. A metà strada tra questi due approcci, le tecniche di omogeneizzazione computazionale sono emerse recentemente come uno strumento promettente che unisce i vantaggi della micro- e macromodellazione. Il problema viene diviso in due scale: la scala strutturale viene trattata come un mezzo omogeneo equivalente, mentre il complesso comportamento della microstruttura eterogenea viene preso in considerazione risolvendo un problema di micro-scala su un volume rappresentativo della microstruttura. Lo scopo di questa ricerca è lo sviluppo di una tecnica di omogeneizzazione computazionale multiscala per l’analisi di strutture in muratura, sottoposte a carichi orizzontali quasi-statici agenti nel piano e fuori dal piano. La teoria classica del continuo di Cauchy è adottata in entrambe le scale, utilizzando quindi la cosiddetta omogeneizzazione computazionale del primo ordine. A causa della natura fragile dei costituenti della muratura, particolare attenzione viene dedicata al problema della local-izzazione delle deformazioni nel modello numerico a danneggiamento distribuito. In questo contesto, la presente ricerca propone un’estensione della regolarizzazione basata sull’energia di frattura al problema di omogeneizzazione a due scale, permettendo l’uso dell’omogeneizzazione computazionale di primo ordine in problemi che coinvolgono localizzazione delle deformazioni. Il metodo viene prima impostato per il caso continuo generale, e viene in seguito applicato all’analisi bidimensionale di pareti a taglio, caricate nel piano, fatte di muratura di mattoni a disposizione periodica. Poi, il suddetto metodo viene esteso al caso di strutture tipo piastra per l’analisi di pareti in muratura caricate fuori dal piano. A questo scopo, si sviluppa una nuova tecnica di omogeneizzazione basata sulla teoria delle piastre spesse. In entrambi i casi di carico nel piano e fuori dal piano, l’accuratezza del metodo proposto è validata mediante il confronto con evidenze sperimentali e con analisi di micro-modellazione. Allo stesso modo, le proprietà di regolarizzazione vengono validate. I risultati ottenuti evidenziano come l’omogeneizzazione computazionale sia uno strumento valido per una valutazione accurata della risposta strutturale delle strutture in muratura, tenendo conto del comportamento complesso della sua microstruttura.
- Published
- 2016
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