INGEGNERIA STRUTTURALE E GEOTECNICA

Seminari

In questa pagina è riportata la programmazione e il dettaglio di tutti i CORSI e SEMINARI organizzati nell'ambito del Dottorato

2024

CORSO - Recenti sviluppi nella progettazione di opere in sotterraneo
2 dicembre 2024, 14:00-18:30 - 3, 4 dicembre 2024, 14:00-17:30 - 5 dicembre 2024, 16:00-18:00 - 6 dicembre 2024, 15:00-18:00 - 9 dicembre 2024, 14:00-18:30 - 10, 11 dicembre 2024, 15:00-17:00 - 12 dicembre 2024, 11:00-13:00
Il corso propone un approfondimento di alcuni temi di notevole interesse per l’analisi del comportamento delle opere in sotterraneo e della loro interazione con l’ambiente, sia durante le fasi costruttive sia durante l’esercizio. Il sempre più intenso sviluppo delle reti infrastrutturali, anche in contesti complessi dal punto di vista geologico, idrogeologico e geotecnico, e l’innalzamento degli standard progettuali richiedono infatti la messa in campo di competenze specialistiche non ancora diffuse nella pratica tecnica e spesso ancora oggetto di studi e ricerche. Le prime lezioni sono dedicate a richiamare le conoscenze di base del settore, dalla caratterizzazione geotecnica per la progettazione di gallerie alle principali soluzioni analitiche per la valutazione dello stato tensio-deformativo nell’intorno del cavo e per l’analisi dell’interazione con le opere di rinforzo e sostegno. Vengono quindi approfonditi gli approcci sia convenzionali sia più avanzati per il progetto di gallerie, nell’ambito sia dello scavo in tradizionale sia dello scavo mediante macchine TBM. Infine, sono trattati, sotto forma di seminari dedicati, i seguenti argomenti: le gallerie sotto falda, la tecnica del congelamento artificiale dei terreni come sostegno provvisorio degli scavi, gli effetti indotti dallo scavo di gallerie superficiali, le verifiche sismiche e le verifiche a fuoco del rivestimento.

CORSO - Corso intitolato a Franco Bontempi: Modellazione e Ottimizzazione Strutturale
25 novembre 2024 - 15:00-18:00, 26-27 novembre 2024 - 10:00-13:00, 15:00-18:00 e 28 novembre 2024 - 10:00-13:00, 14:00-18:00
L’ingegneria strutturale può avvalersi al giorno d’oggi di strumenti computazionali notevolissimi. Questa disponibilità può spingere ad affermare che l’intero processo di progettazione e verifica della qualità di un’opera possa essere automatizzato. Paradossalmente, è vero il contrario: strumenti potenti richiedono profonde riflessioni su quelle che sono le basi della progettazione strutturale al fine di affrontare in modo cosciente e consapevole le procedure di rappresentazione e di ottimizzazione oggi disponibili. In questo modo, l’ottimizzazione può rappresentare una effettiva fondamentale componente della progettazione strutturale, al fine di cercare di massimizzare le prestazioni delle opere e la loro sostenibilità. Per poter ottenere una corretta ottimizzazione, è, quindi, necessario un esame delle radici della progettazione, per comprenderne i significati e valutare i limiti delle diverse implementazioni numeriche. Le lezioni del corso svilupperanno i concetti alla base della ottimizzazione strutturale presentando contemporaneamente puntuali applicazioni significative.

SEMINARIO - World’s tallest full-scale shake table test: NHERI TallWood project
5 novembre 2024, 11:00-12:00
Wood has thousands of years of history as a building material but has also been restricted by building codes and regulations following the industrial revolution. Wood building is viewed as a cost-effective, but less engineered system mainly for low-rise options. Mass timber construction is a relatively new way of utilizing wood material for modern, high performance buildings at both large and small scales. It gives rise to the currently trending conception of wooden sky-scrapers. This presentation will provide an overview of a multi-year research project towards seismically resilient tall wood buildings. Specially, the planning, execution, and results will be discussed from the NSF-funded NHERI TallWood Project which aims at developing a resilience-based seismic design methodology for tall wood buildings. In collaboration with many industry partners, the project team tested a full-scale 10-story mass timber building in 2023 in order to validate a tall mass timber building system that is essentially earthquake proof. This is the world’s tallest full-scale building ever tested on a shake table to date.

CORSO - Mechanics of heterogeneous materials: From homogenization theory to strain localization phenomena
24 ottobre 2024, ore 14:00-17:30 e 25 ottobre 2024, ore 9:00-12:30
The heterogeneous nature of materials like fiber reinforced composites and grains in metallic polycrystals can be used as an asset in the design of optimized microstructures. Averaging methods will be described for stress, strain and energy in order to predict the effective properties. The proposed illustrations deal with elasticity of composites and plasticity of crystals. The concept of representative volume element for random microstructures will be presented. Computational homogenization can be used to predict the failure of materials by strain localization in the form of shear bands. Concepts of loss of uniqueness and loss of ellipticity will be applied to predict shear banding in elastic-plastic dense and porous materials. Finite element simulations of strain localization are characterized by a spurious mesh-dependence of the results. The regularization of these problems requires the introduction of internal lengths in the constitutive model. The strain gradient plasticity theory will be presented and used for this purpose.

CORSO - Seismic Safety and Sustainability: Next Generation of Low-Damage Concrete and Timber Buildings
10, 15 e 23 ottobre 2024 ore 10:00-13:00
The 2010-2011 Canterbury (New Zealand) earthquake sequence has highlighted the severe mismatch between societal expectations over the reality of seismic performance of modern buildings. Life Safety is not enough for modern societies; a paradigm shift in performance-based design criteria and objective towards Damage Control, or low-damage, design philosophy and technologies is urgently required. The ‘bar’ has been raised significantly with the request to fast track the development of what the general public would refer to as the “ultimate” earthquake resisting (towards an “earthquake proof”) building system, capable of sustaining the shaking of a severe earthquake basically unscathed. This short course will provide an overview of recent advances through extensive research, development and implementation, carried out in the past twenty-five years, of an integrated low-damage building system including the skeleton of the superstructure and the non-structural components. Examples of real on site-applications of such low-damage technology in New Zealand and worldwide, using concrete, timber (engineered wood), steel or a combination of these materials, and featuring some of the latest innovative technical solutions developed in the laboratory will be presented as comforting example of successful transfer of performance-based seismic design approach and advanced technology from theory to practice in line with the broader objective of Building Resilience.

SEMINARIO - 3D Concrete Printing: Recent Advancements and Future Trends
9 settembre 2024, 11:00-12:30
3D concrete Printing (3DcP) is a digital construction technology to transform the construction industry by replacing the currently used casting-in-the-mould methods with digitally controlled layer-by-layer additive-construction technology. 3DcP removes the need for formwork (temporary moulds used for casting concrete), thus eliminating a very significant source of waste from construction. Further, the use of standard formworks limits the creativity of architects and options to build varied geometries unless expensive bespoke formworks are produced. This presentation covers the recent advancements in 3DcP technology and the printing process. It also provides information about the printable material requirements and formulations. Further, experimental and numerical techniques to model the pumping and extrusion process of printable concrete will be discussed.

SEMINARIO - The Mission to Apophis
16 luglio 2024, 16:30-17:45
We will present the case for our one great shot to meet asteroid Apophis in 2029. In 2004, an asteroid the size of 5 football fields was discovered and thought to be on a path to impact Earth. It was named Apophis, after the god of Chaos, for its potential to cause widespread global devastation. Subsequent observations have shown that Apophis will barely miss hitting Earth, but on April 13, 2029, it will come so close to Earth’s surface that more than a billion people will see it shinning as brightly as a star moving rapidly across the sky with the naked eye. The event will make the closest Earth flyby of an asteroid in recorded history. While some billion will witness this once-in-a-millennium event, our mission has set sight on harnessing the opportunity to conduct a rare science expedition that would map the surface and interior of Apophis to return data critical to the Earth’s planetary defense. This type of science experiment is only possible once in a lifetime when (1) the subject of observation has been identified early enough for response, (2) is an object of great interest due to its size and trajectory in relation to Earth, and (3) most importantly, coming close enough for our constellation of spacecraft to launch in time to rendezvous with it. Our mission will return data on Apophis’s interior structure, changes in its surface formation, and a photo of the asteroid with Earth in the background. The mitigation of a future threat is a global issue that requires immense advanced coordination and activation. A rendezvous with Apophis will be a defining moment in our collective history as a small team of scientists, technologists, explorers, and risk takers prepare humanity to meet Chaos on our own terms by demonstrating that we are equipped to defend our planet against future asteroids that threaten our existence. With the world watching, are we prepared to meet the moment?

CORSO - Ultrasonic bulk and guided wave propagation in classical and non-classical continua
17 luglio - 10:00-13:00; 18 luglio - 16:00-19:00; 19 luglio - 10:00-13:00, 14:00-17:00
PART I: ULTRASONIC BULK AND GUIDED WAVE PROPAGATION (A. Pau). Being able to handle wave propagation is essential to the understanding of nondestructive evaluation techniques, which enable location and measurement of defects in structures, evaluation of constitutive material constants, and identification of the state of stress. This short course covers selected problems of wave propagation in structures, that is, waves in strings, bulk waves in 3D solids, guided waves, acoustoelasticity, and their application to the solution of materials characterization and image reconstruction problems. PART II: NON-LOCAL CONTINUOUS FORMULATIONS FOR MATERIALS WITH MICROSTRUCTURE AND WAVE PROPAGATION (P. Trovalusci). Focus will be on non local continua with internal lengths and dispersion properties in wave propagation. Non-local continuous formulations for materials with microstructure, including topics such as: discrete-to-scale dependent continuum models, deformations, strain measures, stress measures, balance laws, constitutive equations, thermodynamic restrictions, with applications to composites and masonry, will be covered.

SEMINARIO - Real-time Hybrid Simulation and Application Towards Enhancing Multi-Natural Hazard Civil Infrastructural Resiliency
12 luglio 2024 - 15:00-16:30
Stakeholders are demanding that the performance of the built civil infrastructure be more resilient to natural hazards in order to reduce their impact on society. Performance-based engineering is a means to attempt to meet performance objectives associated with prescribed levels of hazards. A viable technique to meet validation requirements for performance-engineered structural systems is to use real-time hybrid simulation to perform cyber-physical experiments. The complete system is involved in these simulations, where selected components of the system are modeled physically while others are modeled numerically using computational models. The modeling of the former in the physical domain is required because accurate computational models do not exist for these components. In such studies the response modification devices can be coupled to a system that is subjected to a prescribed hazard with a specific return period, enabling system performance under prescribed levels of realistic hazard demands to be established. The talk will present results from recent efforts that the presenter and his research team have completed to advance large-scale multi-directional real-time hybrid simulation. Topics of the talk include an overview of the development of model-based unconditionally stable dissipative explicit direct integration algorithms, explicit state-determination force-based fiber elements, and adaptive servo-hydraulic actuator control algorithms. The real-time integrated control IT architecture used to implement these develops will also be presented. The talk will conclude with applications of these developments to perform real-time hybrid simulations of nonlinear structural systems subjected to earthquake and wind hazards, including extensions to offshore wind turbines, aeroelastic response of tall buildings, and simulations with soil-structure interaction involving machine learning.

SEMINARIO - Structural Reliability under Multiple Loads and Disaster Actions
9 luglio 2024 - 10:00-11:30
The reliability analysis of engineering structures under multiple loads and disaster actions is an unsolved problem in the development of the reliability research. Starting from the mathematical description of the principle of load coincidence, this lecture discusses in detail the analysis method of the structural response under multiple loads and disaster actions. By introducing the physical synthesis method of reliability analysis, a new approach to the structural reliability under multiple loads and disaster actions is suggested. Some specific research examples and engineering applications are presented. The development showed in the lecture make known that the third generation of structural design theory has become a realistic option in the engineering practice.

2023

CORSO - Soft Mechanics and Instabilities
5, 7, 12, 14 dicembre 2023 - 15:00-18:00
Mechanics of soft materials and structures present many interesting aspects from both the point of view of the modeling and the applications. One aspect which will be stressed in the course is related to the large changes in shape which can be expected due to a class of the external stimuli which include mechano-chemical actions. Changes in shape can be smooth or not, with respect to some key control parameter, which depends on the specific problem; when they occur instantaneously, an instability process has taken place. The aim of the short course is to deal with a few problems characterized by instability patterns in soft structures. The course will include: introduction to fundamentals of continuum mechanics, analysis of stress-diffusion problems, introduction of some prototypes of stability loss, analysis of elastic instabilities in soft polymer-based structures driven by chemical and/or mechanical control.

SEMINARIO - New Approaches to Resilience: Policy and Practice
10 novembre 2023, 11:30 - 12:30
The concept of resilience has become part of the lexicon for disaster researchers in universities and government agencies. The concept has evolved significantly over the past 5 years, in part because of experience with the Covid pandemic, and climate change, and in part because recent disasters have overwhelmed humanitarian aid and recovery programs. There are simply not sufficient resources to meet recovery needs (particularly housing) in a timely fashion. While there are many important lessons from successful recoveries in many countries, it has become clear that countries with high disaster risk must develop more extensive government capacity in their critical services such as schools and health care, business, infrastructure, and housing sectors – before a disaster strikes. It is important to discuss what goes wrong and what works with case studies from multiple disasters, but equally important to consider policies and programs that are designed to improve capacity as an ex-ante recovery measure. One example is investment in the creation of housing programs, community planning, housing standards, and training for construction programs to improve government capacity to meet baseline, more equitable housing needs in the immediate term, but also help hazard-exposed countries reduce housing losses in future disasters. There are similar opportunities for resilience through investment in infrastructure, schools, health care, and other services.

SEMINARIO - Tall Timber Buildings: Past, Present and Future
20 settembre 2023, ore 12:00-13:00
A rapid growth of urban populations and associated environmental concerns are challenging city planners and developers to consider sustainable building systems. In response, with new CLT and glulam timber technology, mid- and high-rise timber buildings are becoming attractive solution. Current objective-based design approaches in the NBCC 2020, however need additional provisions to cover the unique design challenges posed by such tall timber-based hybrid buildings. These challenges span from: a lack of seismic force modification factors calibrated with the notion of collapse risk, to a lack of wind design guidelines to satisfy the serviceability and strength criteria. In the first part of the talk, the current state-of-the-art in timber-based hybrid systems (e.g., timber-steel and timber-concrete) together with ongoing design and research challenges will be presented. The second part of the talk will focus on findings of a recently completed project sponsored by the Forestry Innovation Investment's (FII) Wood First Program. In the project, new force modification factors to supplement the NBCC 2015 are developed using the FEMA P-695 collapse risk approach. These factors will be presented together with the associated collapse risks obtained through nonlinear dynamic analysis. It will highlight the rigorously selected ground motions for Vancouver related seismicity in congruence with the 2015 NBCC code. Finally, current state of the art and future direction in tall timber design are highlighted.

CORSO - Ultrasonic bulk and guided wave propagation in classical and non-classical continua
6 settembre 2023, 10:00-12:00 e 15:00-17:00, 7 settembre 2023, 15:30-18:30, 8 settembre 2023, 10:00-13:00 e 15:00-17:00
Being able to handle wave propagation is essential to the understanding of nondestructive evaluation techniques, which enable location and measurement of defects in structures, evaluation of constitutive material constants, and identification of the state of stress. This short course covers selected problems of wave propagation in structures, that is, waves in strings, bulk waves in 3D solids, guided waves, acoustoelasticity, and their application to the solution of materials characterization and image reconstruction problems. Focus will be also on non-local continua with internal lengths and dispersion properties in wave propagation.

SEMINARIO - The relaxed micromorphic model- a generalization of the Cosserat model
18 luglio 2023, 17:00-18:00
One of the best known generalized continuum models is the Cosserat -micropolar Model which features classical displacements and additional Microrotations as independent degrees of freedom. In this talk I consider the linear Cosserat model and I present an alternative way of writing its curvature term based on Nyes dislocation tensor. This allows to see that the model admits a straight forward generalization into the relaxed micromorphic model. This model has the full micromorphic degrees of freedom but a curvature measure akin to the Cosserat Model. Basic features of the new model (existence, analytical solutions, regularity, FEM) are presented and it is shown that it offers decisive advantages compared to the Cosserat model while it retains a simple structure than the classical micromorphic model.

SEMINARIO - Corrosion and its control in prestressed concrete structures
10 luglio, 2023, ore 12:00
Many prestressed concrete (PSC) structures have been built with an anticipated service life of 100+ years. However, many of them have experienced premature corrosion of strands and eventual tendon/girder/bridge failures within a few decades. Hence, reviewing earlier assumptions on corrosion properties used for durability-design purposes and developing methods to build PSC structures with “corrosion-free” service lives of 100+ years is important. For conventional and pretensioned concrete structures, the chloride threshold is a key service life parameter. It is the minimum amount of chlorides required to initiate corrosion of steel-cementitious (S-C) systems and no suitable test methods are available to determine this. This prevents engineers from choosing durable material-combinations to achieve the target service life of 100+ years. In this presentation, the development of a test method and determination of chloride threshold for various S-C systems with various binders, corrosion inhibitors and prestressing steel (i.e., 50% less than conventional steel!) will be presented. Also, nomograms (that consider the cover depth, chloride threshold, binder types, chloride diffusion coefficient, and concrete resistivity) for durability-design of pretensioned concrete structures will be presented. In case of post tensioned (PT) concrete structures, the presence of air voids (due to the inadequate grouting) has been cited as the major reason for corrosion of prestressed strands. Refilling of such voided tendons with new grout can lead to galvanic corrosion and is not recommended. Also, the replacement of corroded tendons is very expensive and cumbersome. Hence, a new non-invasive method to control the corrosion of strands in PT systems with voids has been developed using chemical treatments and cathodic protection techniques. These techniques that can save huge inventory of PT bridge tendons will also be presented.

CORSO - Hands on Continuum Mechanics with COMSOL
19, 21, 23, 26 giugno 2023 – 9:00-13:00
The goal of this course is to understand the fundamentals of continuum mechanics through worked examples. Participants will tackle some typical problems of continuum mechanics, and will learn to implement a given problem using the weak formulation into the COMSOL software and to discuss the solution.

CORSO - Interazione Terreno-Struttura
12,13,15,16 giugno 2023, 10:30-12:30 / 14:00-16:00
Nell’ingegneria civile il comportamento meccanico del terreno e degli elementi strutturali viene descritto attraverso il comune strumento della meccanica dei solidi. Sembrerebbe perciò logico studiare il problema dell'interazione terreno-struttura attraverso una trattazione unificata, nella quale i due materiali a contatto siano semplicemente dotati di proprietà meccaniche diverse. Invece, per le specificità del comportamento dei terreni e delle strutture, per le tradizioni applicative delle discipline dell'ingegneria geotecnica e strutturale e per le difficoltà concettuali e pratiche di un approccio unificato, nella pratica ciascun problema applicativo viene affrontato introducendo forti semplificazioni, legate e commisurate allo scopo per il quale si esegue l'analisi. Per effetto delle azioni statiche, lo studio dell'interazione terreno struttura è principalmente rivolto alla determinazione delle sollecitazioni negli elementi strutturali e degli spostamenti dei sistemi geotecnici (fondazioni, scavi, gallerie) che a loro volta possono indurre effetti significativi nelle costruzioni esistenti. Le azioni sismiche producono specifici aggiuntivi, poiché le caratteristiche del terreno e degli elementi strutturali determinano la risposta dinamica del sistema, e lo studio dell'interazione terreno-struttura deve rivolgersi principalmente a questo aspetto. In questo contesto, il corso esamina i casi nei quali la soluzione di un problema applicativo è legata all'interazione fra terreno ed elementi strutturali, illustrando le principali tecniche di analisi, mostrandone l'applicabilità e i limiti in relazione agli obiettivi dell'analisi e considerando sia gli effetti delle azioni statiche, sia quelli indotti dalle azioni sismiche.

CORSO - An innovative approach to static and dynamic topology optimization with practical applications
10 maggio 2023 ore 14:00-18:00, 11 maggio 2023 ore 9:00-13:00
An innovative approach to topology optimization is presented that is based on the minimization of a proper norm of the input/output transfer matrix G. The singular value decomposition (SVD) of G is shown to be the key ingredient of the proposed optimization strategy that applies to static and dynamic topology optimization, with nearly no modifications. Alongside the theoretical derivations, the class is introduced to the coding of the proposed approach in the Matlab environment as far as the static regime is concerned, whereas hints are given for the extension to dynamic response. The optimization of exoskeletal systems that minimize the response of 3D framed structures to horizontal environmental actions is one of the results of practical interest that are achieved.

SEMINARIO - Minimal surface tensegrity networks
28 aprile 2023, 10:00-12:00
The exploration of new configurations of tensegrity structures is expected to contribute to the expansion of the applications of the tensegrity concept in building design. Minimal surface tensegrity networks are double layer tensegrity structures, composed of tensegrity units of square base, with the two layers being minimal surfaces. Design algorithms that integrate methods for tessellating minimal surfaces with square tiles, while considering the geometric and stability constraints of double layer tensegrity networks, are used to generate tensegrity structures of catenoid, helicoid, and enneper shapes. The developed algorithms and computational processes were applied and tested during the design and actual construction of three minimal surface tensegrity structures-installations, which were displayed in international exhibitions and will also be presented and discussed.

2022

CORSO - Recenti sviluppi nella progettazione di opere in sotterraneo
5, 6, 7,12,13,14,15,16, 20 dicembre 2022
Il corso propone un approfondimento di alcuni temi di notevole interesse per l’analisi del comportamento delle opere in sotterraneo e della loro interazione con l’ambiente, sia durante le fasi costruttive sia durante l’esercizio. Il sempre più intenso sviluppo delle reti infrastrutturali, anche in contesti complessi dal punto di vista geologico, idrogeologico e geotecnico, e l’innalzamento degli standard progettuali richiedono infatti la messa in campo di competenze specialistiche non ancora diffuse nella pratica tecnica e spesso ancora oggetto di studi e ricerche. Le prime lezioni sono dedicate a richiamare le conoscenze di base del settore, dalla caratterizzazione geotecnica per la progettazione di gallerie alle principali soluzioni analitiche per la valutazione dello stato tensio-deformativo nell’intorno del cavo e per l’analisi dell’interazione con le opere di rinforzo e sostegno. Vengono quindi approfonditi gli approcci tradizionali e più avanzati per il progetto di gallerie nell’ambito dello scavo in tradizionale e meccanizzato mediante macchine TBM. Infine, sono trattati, sotto forma di seminari dedicati, i seguenti argomenti: verifiche sismiche, interazione pendii-gallerie, verifiche a fuoco, effetti indotti dallo scavo di gallerie superficiali e gallerie sotto falda

CORSO - An introduction to the mechanics of soils
22 novembre 2022, 09:30-11:30, 12:30-13:30, 14:30-16:00; 23-24 novembre 2022, 10:00-12:30, 14:00-16:00
This 3 days course is aimed at introducing, at the post-graduate level, the basic principles of the mechanics of soils by discussing some of their experimental features and constitutive modelling strategies, with particular emphasis to clayey materials. The fundamental field equations for a two-phase medium are first derived, followed by an overview of typical experimental results and their interpretation in the frame of Critical State Soil Mechanics. The key ingredients of plasticity theory are then introduced, first under 1D conditions and then generalised to 3D ones, aiming at providing the general theoretical setting then adopted to illustrate a wide class of plasticity-based models for soils, ranging from standard perfectly plastic ones to more advanced mixed-hardening multi-surface formulations. Finally, an alternative constitutive approach based on thermodynamics with internal variables is introduced and its merits are illustrated with reference to different forms of elasto-plastic coupling of soils.

CORSO - Seismic Safety and Sustainability:Next Generation of Low-Damage Concrete and Timber Buildings
15-17-18 novembre 2022 - 10:00-13:00
The severe socio-economic impact of recent earthquake events have further highlighted, on one hand, the severe mismatch between societal expectations over the reality of seismic performance of modern buildings, while confirming, on the other hand, the crucial need for a coordinated seismic risk reduction plans at a national level. Life Safety is not enough for modern societies; a paradigm shift in performance-based design criteria and objective towards Damage Control, or low-damage, design philosophy and technologies is urgently required. The increased awareness by the general public/tenants, building owners, territorial authorities as well as insurers/reinsurers, of the severe economic impacts of moderate-strong earthquakes in terms of damage/dollars/downtime has indeed stimulated and facilitated the wider acceptance and implementation of cost-efficient damage-control, or low-damage, technologies. The ‘bar’ has been raised significantly with the request to fast track the development of what the general public would refer to as the “ultimate” earthquake resisting (towards an earthquake proof?) building system, capable of sustaining the shaking of a severe earthquake basically unscathed,. This short course will provide an overview of recent advances through extensive research, development and implementation, carried out in the past twenty years, of an integrated low-damage building system including: the skeleton of the superstructure, the non-structural components and the interaction with the soil/foundation system. Examples of real on site-applications of such technology in New Zealand, using concrete, timber (engineered wood), steel or a combination of these materials, and featuring some of the latest innovative technical solutions developed in the laboratory will be presented as comforting example of successful transfer of performance-based seismic design approach and advanced technology from theory to practice in line with the broader objective of Building Resilience.

CORSO - Introduction to Nano-mechanics: Continuum Modeling and Atomistic Simulation
9-10-11 novembre 2022 - 10:00-13:00
Nanotechnology deals with design, characterization and production of structures at the nano-scale. It has a broad application in different scientific sectors encompassing engineering, the automotive industry, renewable energy generation, tissue engineering and information technology. Nano-mechanics is one of the essential sub-fields of nanotechnology, focusing on the mechanical evaluation of nano-structures and nano-systems. In nano-mechanics, besides the experimental efforts, which may be formidable and expensive, there are three main approaches: (1) continuum modelling, (2) atomistic modelling, generally admitted as numerical experiments and (3) multi-scale modelling, which hybridizes the accuracy of atomistic simulation and efficiency of continuum description. In this course, first, a general overview of nano-mechanics and modelling approaches at nano-scale will be provided. The second part will present an introduction to the molecular dynamics (MD) simulations as an atomistic modelling technique. In the third part, the attendees will be acquainted with the implementation of MD in Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) open-source software.

CORSO - Soft Mechanics and Instabilities
25, 26, 27 e 28 ottobre 2022 - 12:00-13:00, 14:00-16:00
Mechanics of soft materials and structures present many interesting aspects from both the point of view of the modeling and the applications. One aspect which will be stressed in the course is related to the large changes in shape which can be expected due to a class of the external stimuli which include mechano-chemical actions. Changes in shape can be smooth or not, with respect to some key control parameter, which depends on the specific problem; when they occur instantaneously, an instability process has taken place. The aim of the short course is to deal with a few problems characterized by instability patterns in soft structures. The course will include: introduction to fundamentals of continuum mechanics, analysis of stress-diffusion problems, introduction of some prototypes of stability loss, analysis of elastic instabilities in soft polymer-based structures driven by chemical and/or mechanical control.

SEMINARIO - Thrust Network Analysis of Masonry Vaults
14 ottobre 2022 - ore 16:00-16:45
We address the Thrust Network Analysis (TNA), i.e. the methodology for modeling masonry vaults as a discrete network of forces in equilibrium with gravitational loads, first contributed by O’Dwyer and fully developed by Block and coworkers. Reducing the bias by the quoted authors in favor of a graphical interpretation of the method, we reformulate the original version of the TNA in order to significantly enhance the computational performances. The proposed reformulation of the TNA is also extended in a twofold manner, i.e. by including horizontal forces in the analysis and holes or free edges in the vault. Furthermore, the coefficient matrices entering the solution scheme are obtained by assembling the separate contribution of each branch, thus avoiding ad hoc node numbering and branch orientation required by alternative implementations. Numerical examples, some of which referred to vaults having a particularly complex geometry, show the effectiveness and robustness of the proposed approach in assessing the safety conditions of existing masonry vaults or in designing new ones.

SEMINARIO - Recent Advancements in the Modeling of Hysteretic Phenomena for Mechanical Systems and Materials
14 ottobre 2022 - ore 17:15-18:00
The number and nature of hysteretic responses typically exhibited by mechanical systems and materials are so huge that their modeling and identification are usually carried out on an ad-hoc basis. Thus, with the aim of proposing a unified approach to the modeling of rate-independent hysteretic behavior, we first perform a detailed classification of complex generalized force–displacement hysteresis loops, ranging from the asymmetric, pinched, S-shaped, flag-shaped ones to those obtained by their arbitrary combination, since they typically span the vast majority of loops obtained experimentally. Subsequently, we formulate a novel rate-independent hysteretic model, having an exponential nature, that offers a series of advantages over other hysteretic models available in the literature. Indeed, it adopts closed form expressions for evaluating the output variable, with important benefits in terms of computational efficiency and implementation ease, and it allows for an uncoupled modeling of the generic loading and unloading phases by means of two different sets of eight parameters. In addition, it requires the use of a simple identification procedure thanks to the clear theoretical and/or experimental interpretation of the adopted parameters. The accuracy of the proposed model is experimentally and numerically validated and its computational efficiency is demonstrated. In particular, the experimental validation is carried out by reproducing four different types of complex experimental hysteresis loops retrieved from the literature, whereas the numerical validation is performed by running some nonlinear time history analyses on a single degree of freedom mechanical system and comparing the results with those obtained by using a modified version of the celebrated Graesser–Cozzarelli model.

SEMINARIO - Out-of-plane instability of ductile reinforced concrete structural walls: Failure mechanism and key design recommendations
26 settembre 2022 dalle 17:00 alle 18:00
Following observations of out-of-plane instability in slender ductile structural walls in some recent earthquakes, this mode of wall failure has been and is being investigated by several research groups. Analytical, numerical and experimental investigations have been conducted to study this failure mechanism as well as its controlling parameters. Both singly reinforced and doubly reinforced concrete walls have been studied under uni-directional and bi-directional loading. A simplified approach making use of concrete columns representing boundary zones of rectangular walls has also been used to reduce the computational and experimental costs of the research programs. This presentation provides a state-of-the-art on the research conducted on this failure mechanism and elaborates on the sequence of events resulting in its development in structural walls, including the effect of governing parameters such as wall section thickness, length, axial load, and longitudinal reinforcement ratio. Suitability of the existing requirements in the New Zealand Concrete Design Standard (NZS 3101:2006-A3) for prevention of this failure mechanism is also evaluated and several key design recommendations are discussed in light of the numerical and experimental studies conducted at the University of Canterbury.

CORSO - Pile foundations under seismic loading
18, 20 e 21 luglio 2022 - 14:30-17:30, 10:00-13:00, 11:00-13:00
Pile foundations are the most common deep foundations used around the world to transfer super-structure loads into competent soil strata, particularly when poor soil strata exist at the ground surface. Many buildings in the seismic regions of the world are supported on pile foundations and therefore experience strong seismic loading particularly if the ground suffers liquefaction. It is often very difficult to investigate the performance of pile foundations under such conditions. In this course, we will cover the use of dynamic centrifuge modelling to investigate the seismic behaviour of pile foundations, particularly when soil liquefaction occurs. By using the experimental data from centrifuge tests, we will discover the failure mechanisms that can occur in single piles and in pile groups. We will look at the load the load transfer mechanisms that can occur once liquefaction of soil sets in and also the settlement of piles following soil liquefaction. We will estimate the amount of settlement that pile foundations can suffer. Overall, this course should give you an overview of the design of pile foundations in liquefiable soils.

CORSO - Ultrasonic wave propagation in classical and non-classical continua. Applications to material characterization, damage imaging and stress monitoring
12-14-15 luglio 2022 - 15:00-17:00
Being able to handle wave propagation is essential to the understanding of nondestructive evaluation techniques, which enable location and measurement of defects in structures, evaluation of constitutive material constants, and identification of the state of stress. This short course covers selected problems of wave propagation in structures, that is, waves in strings, bulk waves in 3D solids, guided waves, acoustoelasticity, and their application to the solution of materials characterization and image reconstruction problems.

2021

CORSO - Seismic Safety and Sustainability:Next Generation of Low-Damage Concrete and Timber Buildings
22-24-26 novembre 2021 - 10:00 - 13:00
The severe socio-economic impact of recent earthquake events have further highlighted, on one hand, the severe mismatch between societal expectations over the reality of seismic performance of modern buildings, while confirming, on the other hand, the crucial need for a coordinated seismic risk reduction plans at a national level. Life Safety is not enough for modern societies; a paradigm shift in performance-based design criteria and objective towards Damage Control, or low-damage, design philosophy and technologies is urgently required. The increased awareness by the general public/tenants, building owners, territorial authorities as well as insurers/reinsurers, of the severe economic impacts of moderate-strong earthquakes in terms of damage/dollars/downtime has indeed stimulated and facilitated the wider acceptance and implementation of cost-efficient damage-control, or low-damage, technologies. The ‘bar’ has been raised significantly with the request to fast track the development of what the general public would refer to as the “ultimate” earthquake resisting (towards an earthquake proof?) building system, capable of sustaining the shaking of a severe earthquake basically unscathed,. This short course will provide an overview of recent advances through extensive research, development and implementation, carried out in the past twenty years, of an integrated low-damage building system including: the skeleton of the superstructure, the non-structural components and the interaction with the soil/foundation system. Examples of real on site-applications of such technology in New Zealand, using concrete, timber (engineered wood), steel or a combination of these materials, and featuring some of the latest innovative technical solutions developed in the laboratory will be presented as comforting example of successful transfer of performance-based seismic design approach and advanced technology from theory to practice in line with the broader objective of Building Resilience.

CORSO - Ottimizzazione Strutturale
25, 26, 29 ottobre, 2021 ore 10-13, 15-18
L’ingegneria strutturale può avvalersi al giorno d’oggi di strumenti computazionali notevolissimi. Questa disponibilità può spingere ad affermare che l’intero processo di progettazione e verifica della qualità di un’opera possa essere automatizzato. Paradossalmente, è vero il contrario: strumenti potenti richiedono profonde riflessioni su quelle che sono le basi della progettazione strutturale al fine di affrontare in modo cosciente e consapevole le procedure di rappresentazione e di ottimizzazione oggi disponibili. In questo modo, l’ottimizzazione può rappresentare una effettiva fondamentale componente della progettazione strutturale, al fine di cercare di massimizzare le prestazioni delle opere e la loro sostenibilità. Per poter ottenere una corretta ottimizzazione, è, quindi, necessario un esame delle radici della progettazione, per comprenderne i significati e valutare i limiti delle diverse implementazioni numeriche. Le lezioni del corso svilupperanno i concetti alla base della ottimizzazione strutturale presentando contemporaneamente puntuali applicazioni significative.

CORSO - Dinamica delle Strutture
27-28-30 settembre 2021
Programma sintetico: A. Problema dinamico. Modellazione, mitigazione e monitoraggio strutturale (3 ore) B. Caso studio di laboratorio: modello fisico in scala (3 ore) C. Caso studio in situ: la torre civica del Comune di Rieti (3 ore)

CORSO - Multiscale Modelling in Composites
20-21-22 settembre 2021 - 9:30-18:00
In recent years many fields of engineering and architecture have seen a significant increase in the production and application of composite materials, ranging from ceramic and metal matrix composites, fibre reinforced, but also masonry, rocks, geo and bio materials. This doctoral course presents series of lessons and seminars by researchers specialized in multiscale and multifield modelling and simulation of composite materials described as is materials with internal structure at the nano, micro or meso-levels and complex behaviour, such as damage, plasticity, etc. These lectures deals with materials science, theoretical mechanics, experimental and computational techniques at different scales, providing a sound base and a framework for many applications, which are hitherto treated in a phenomenological sense. The basic principles are formulated of multiscale modelling strategies towards modern complex multiphase materials subjected to various types of mechanical, thermal and environmental effects. Various homogenization/multiscale strategies will be presented and discussed. Attention is also focused on the historical origins of multiscale modeling and foundations of continuum mechanics currently adopted to model non-classical continua with substructure, for which internal length scales play a crucial role.

CORSO - Ultrasonic wave propagation in solid media with applications to stress monitoring, imaging and materials characterization
21-22-23 luglio 2021, ore 15:00-17:00
Being able to handle wave propagation is essential to the understanding of nondestructive evaluation techniques, which enable location and measurement of defects in structures, evaluation of constitutive material constants, and identification of the state of stress. This short course covers selected problems of wave propagation in structures, that is, waves in strings, bulk waves in 3D solids, guided waves, acoustoelasticity, and their application to the solution of materials characterization and image reconstruction problems.

CORSO- Direct and Inverse Dynamic Problems in Random Vibrations
7-8 giugno, 2021 ore 10-13
The course will introduce the theory and the methods of random vibrations and probabilistic engineering mechanics. A wide range of engineering applications require simulation and estimation of loads and excitations that are random in nature as they are often associated with hazards such as earthquakes, winds, waves, etc. The module will provide both fundamentals and application examples. A practical tutorial is also planned.

CORSO - Costruzioni Esistenti in Muratura “Marcello Ciampoli” - Edizione 2021
dal 24 maggio al 3 giugno 2021
Il corso intende fornire un quadro generale delle problematiche relative al comportamento strutturale delle costruzioni murarie esistenti, con riferimento alla sicurezza nei confronti dell'azioni sismiche. Il punto di partenza riguarda sia la definizione dei termini scientifici e tecnici implicati, sia anche le necessarie considerazioni di valore storico e artistico. Particolare attenzione sarà rivolta alla modellazione meccanica delle costruzioni in muratura, che costituiscono larga parte del patrimonio storico architettonico italiano e all'acquisizione di una specifica strumentazione di calcolo per le analisi strutturali necessarie a verificarne e garantirne il corretto funzionamento meccanico, problematica che non può ritenersi estranea a quella che investe le tematiche proprie della storia e del restauro architettonico.

CORSO - Elementi Finiti
3-6 maggio, 2021 ore 11-14, 4-7 maggio, 2021 ore 15-18
Il corso fornisce le basi del metodo degli Elementi Finiti (EF) per la soluzione approssimata di problemi di meccanica, con particolare riferimento alla meccanica strutturale. Si illustrano la formulazione classica agli spostamenti, sulla quale si basano la maggior parte dei programmi di calcolo in uso, e le formulazioni miste a due e tre campi. Si introducono le principali famiglie di EF utilizzate per la soluzione di problemi 1D, aste e travi, 2D, lastre e piastre, e 3D, solidi e gusci. Si approfondiscono, infine, alcuni aspetti legati a note patologie numeriche e alle relative strategie di soluzione.

CORSO - Interazione Terreno-Struttura
13-16-20-21-23 aprile 2021, 9:30-12:45
Dato che il comportamento del terreno e degli elementi strutturali viene descritto attraverso il comune strumento della meccanica dei solidi, in linea di principio sembrerebbe logico studiare il problema dell'interazione terreno-struttura attraverso una trattazione unificata, nella quale i due materiali a contatto siano semplicemente dotati di proprietà meccaniche diverse. La realtà è piuttosto diversa: per le specificità del comportamento dei terreni e delle strutture, per le tradizioni applicative delle discipline dell'ingegneria geotecnica e strutturale e per le difficoltà concettuali e pratiche di un approccio unificato, nella pratica ciascun problema applicativo viene affrontato introducendo forti semplificazioni, legate e commisurate allo scopo per il quale si esegue l'analisi. Per effetto delle azioni statiche, lo studio dell'interazione terreno struttura è principalmente rivolto alla determinazione delle sollecitazioni negli elementi strutturali e degli spostamenti dei sistemi geotecnici (fondazioni, scavi, gallerie) che a loro volta possono indurre effetti significativi nelle costruzioni esistenti. Le azioni sismiche producono specifici effetti aggiuntivi, poiché le caratteristiche del terreno e degli elementi strutturali determinano la risposta dinamica del sistema, e lo studio dell'interazione terreno-struttura deve rivolgersi principalmente a questo aspetto. In questo contesto, il corso esamina i casi più frequenti nei quali la soluzione di un problema applicativo è legata all'interazione fra terreno ed elementi strutturali, illustrando le principali tecniche di analisi, mostrandone l'applicabilità e i limiti in relazione agli obiettivi dell'analisi ed esaminando separatamente gli effetti delle azioni statiche da quelli relativi alle azioni sismiche.

CORSO - Metodi Variazionali nella Meccanica dei Materiali
7-8-9 aprile 2021 ore 10:00-13:00
Il corso intende dare una panoramica moderna sulla riformulazione variazionale di alcuni problemi classici di plasticità e frattura. Saranno esaminati i principi di minimo che permettono di ottenere la plasticità alla von Mises e à la Drucker-Prager. Infine sarà presentato un modello accoppiato di plasticità e danno che si è dimostrato molto efficace nella descrizione dei fenomeni di frattura coesiva.

2020

CORSO - Una introduzione alla meccanica dei terreni
9-10-11 dicembre 2020 - ore 11-13 e 14-16

SEMINARIO - L'attraversamento della valle del Polcevera, il vecchio e il nuovo ponte
27 novembre 2020, ore 11:00
Dopo una breve esposizione delle caratteristiche e conformazione del vecchio ponte Morandi, vengono discussi aspetti di concezione architettonica e strutturale del nuovo ponte S. Giorgio a Genova, per approfondire poi le fasi costruttive dell’opera con la loro analisi numerica, sottolineando gli aspetti di interazione fra modellazione, sviluppo della progettazione e attività di cantiere.

SEMINARIO - Comportamento Strutturale di Profili in FRP: Sperimentazione e Applicazioni
19 novembre 2020, ore 15:00
L’impiego in ambito strutturale dei materiali FRP (Fiber Reinforced Polymer), sia per nuove costruzioni sia nel settore del rinforzo del patrimonio esistente, storico e moderno, costituisce ormai pratica consolidata, peraltro supportata da un consistente quadro normativo di riferimento e numerose pubblicazioni scientifiche. Molto noti e con ampio utilizzo sono i materiali FRP impiegati a mezzo di incollaggio, con lamine o con tessuti, mentre minore sviluppo applicativo hanno avuto le barre di rinforzo e i profili strutturali. In quest’ultimo caso, detti profili sono di particolare interesse ed hanno potenzialità ancora non completamente sviluppate. Il tal senso il seminario si propone di evidenziare quali siano i metodi di analisi e di calcolo disponibili, le sperimentazioni effettuate e in corso, e le applicazioni di maggior rilievo in ambito strutturale. In dettaglio, si tratta di elementi prodotti perlopiù a mezzo di processo di pultrusione, caratterizzati da un comportamento anisotropo trasversalmente isotropo, di notevole leggerezza, e con resistenze comparabili ai profili di carpenteria metallica. In relazione al loro comportamento nel tempo e ai temi di durabilità, risultano particolarmente performanti rispetto ai tradizionali materiali strutturali. Possono essere realizzati con distinti tipi di fibra di rinforzo e matrice, in funzione del tipo di impiego strutturale. Allo stato attuale esistono numerose applicazioni, in Italia e all’estero, nel campo del miglioramento sismico, nel rinforzo puntuale, nell’accoppiamento con altri materiali strutturali in sezioni composte, nel settore delle realizzazioni permanenti ed emergenziali o temporanee. Il seminario si sofferma inoltre sui temi più specificatamente accademico-scientifici, e di ricerca, relativi alle connessioni, bullonate o incollate, e ai problemi legati agli effetti del secondo ordine. A conferma dell’importanza teorica e applicativa del tema, sono proposti anche alcuni cenni all’ Eurocodice, in corso di ultimazione, interamente dedicato all’impiego dei profili strutturali in FRP.

SEMINARIO - Hydro-mechanical instabilities in partially saturated geomaterials: fingering and fracturing
30 Ottobre 2020
Fluid fingering and strain localization are manifestations of possibly coupled instability in geomaterials. In order to capture these two phenomena and their possible interaction a phase field approach to partially saturated porous media is adopted, considering the mixture of a liquid and a gas as a Cahn-Hilliard non-uniform fluid; the behavior of the solid skeleton is described extending the variational phase-field approach to fracture to partially saturated porous media within the framework of poromechanics. The proposed model is capable to capture the effects of the fluid fingering on the strain and stress distributions under hydraulic loading (drainage and imbibition) and vice-versa the effects of fracturing and strain localization on the heterogeneous fluid flow through the porous medium. A parallel experimental campaign is also in progress in order to identify fluid fingering nucleation and propagation and to measure the induced localized strains via a new biaxial apparatus specially designed for this project.

CORSO - Seismic Safety and Sustainability: New Generation of Low Damage Systems in Prefabricated Concrete or Laminated Wood
19-21-23 Ottobre 2020
The severe socio-economic impact of recent earthquake events have further highlighted, on one hand, the severe mismatch between societal expectations over the reality of seismic performance of modern buildings, while confirming, on the other hand, the crucial need for a coordinated seismic risk reduction plans at a national level. Life Safety is not enough for modern societies; a paradigm shift in performance-based design criteria and objective towards Damage Control, or low-damage, design philosophy and technologies is urgently required. The increased awareness by the general public/tenants, building owners, territorial authorities as well as insurers/reinsurers, of the severe economic impacts of moderate-strong earthquakes in terms of damage/dollars/downtime has indeed stimulated and facilitated the wider acceptance and implementation of cost-efficient damage-control, or low-damage, technologies. The ‘bar’ has been raised significantly with the request to fast track the development of what the general public would refer to as the “ultimate” earthquake resisting (towards an earthquake proof?) building system, capable of sustaining the shaking of a severe earthquake basically unscathed,. This course will provide an overview of recent advances through extensive research, development and implementation, carried out in the past twenty years, of an integrated low-damage building system including: the skeleton of the superstructure, the non-structural components and the interaction with the soil/foundation system. Examples of real on site-applications of such technology in New Zealand, using concrete, timber (engineered wood), steel or a combination of these materials, and featuring some of the latest innovative technical solutions developed in the laboratory will be presented as comforting example of successful transfer of performance-based seismic design approach and advanced technology from theory to practice in line with the broader objective of Building Resilience.

CORSO - Dinamica delle Strutture
14-16-18 settembre 2020

CORSO - Automated Computational Modelling in Mechanics (Università Roma Tre)
7-8-14-15 settembre 2020
The course is organized by the Doctoral School in Civil Engineering of the University Roma Tre. No fees are requested, but reservation is needed. Those wishing to attend the course should contact the Department of Engineering at the following address.

CORSO - Direct and Inverse Dynamic Problems in Random Vibrations
3, 6, 8, 10 luglio
Introduction to the theory and methods of random vibrations and probabilistic engineering mechanics. A wide range of engineering applications require simulation and estimation of loads and excitations that are random in nature as they are often associated with hazards such as earthquakes, winds, waves, etc. The module will provide both fundamentals and application examples. A practical tutorial is also planned.

SEMINARIO - MIDAS FEA NX
23 giugno ore 15:00
Il software Midas FEA NX è uno strumento di modellazione solida FEM per risolvere problemi di ingegneria civile e meccanica rappresentando al meglio la geometria solida che si vuole simulare. Per esempio dettagli di nodi in acciaio o in c.a., dispositivi e provini di laboratorio, dettagli strutturali, ma anche strutture intere come basiliche, ponti in muratura, strutture voltate in generale. Presenta l'Ing. Carlo Tuzza

Appendice al corso Murature Esistenti 'Marcello Ciampoli'. Un caso di studio: la cupola del Duomo di Pisa. Indagini storiche, analisi sperimentali e strutturali.
4 giugno 2020 ore 16:00
Un caso di studio: la cupola del Duomo di Pisa. Indagini storiche, rilievo con laser scanner, rappresentazione analitica superfici, prove sperimentali in situ e in laboratorio, analisi strutturali. Dr. Francesco Barsi, University of Pisa

2019

Wind-induced Vibrations on Long – Span Bridges: Importance of Wind Load Uncertainty Propagation - Luca Caracoglia Department of Civil and Environmental Engineering, Northeastern University, Boston, Massachusetts, USA
11 Dicembre 2019

Sicurezza in caso di incendio su edifici storici. Modellazione ed esodo.
24 Maggio 2019
L’articolato campo della prevenzione incendi abbraccia molti settori, dall’edilizia civile a quella industriale senza tralasciare anche il settore storico-monumentale. D’altronde è risaputo che il rischio incendi investe spesso edifici a carattere storico (biblioteche, archivi, teatri, ecc.), ove tali manufatti edilizi impongono un oculato adeguamento che a volte, si discosta dalle classiche regole per gli innumerevoli vincoli architettonici ed estetici. Alla luce dei concetti introdotti dal nuovo codice di prevenzione incendi del 3 agosto 2015 l’obiettivo dei seminari è quello di divulgare precise indicazioni, anche mediante l’uso di modellazione computerizzate, relative al sistema di esodo con l’intento di assicurare che gli occupanti possano raggiungere o permanere in un luogo sicuro, a prescindere dall’intervento dei Vigili del fuoco.

AN INVITATION TO ERGODIC THEORY WITH A VIEW TOWARDS MATHEMATICAL BILLIARDS _ II
7 Febbraio 2019
.A mathematical billiard is the mechanical system of a point particle traveling in a planar domain subject only to elastic collisions with the boundary of the domain (assumed to be infinitely massive). Systems of this kind have wide application in the physical sciences. I will start by giving a light but mathematically rigorous description of a billiard system, trying to show what features of this description lead to the observed properties of the dynamics (e.g., regular, chaotic, etc.). Ergodic theory is the branch of mathematics that studies the properties of a “dynamical system” from a stochastic/probabilistic point of view. It is the main and perhaps only mathematical tool to study systems, such as chaotic billiards, that admit no exact prediction. I will introduce the most basic notions of ergodic theory, together with some elementary examples of dynamical systems, with a view towards the paradigm of the chaotic billiard.

Promoting societal well-being by designing sustainable and resilient infrastructure: Engineering tools and broader interdisciplinary considerations.
18 Marzo 2019
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AN INVITATION TO ERGODIC THEORY WITH A VIEW TOWARDS MATHEMATICAL BILLIARDS _ I
4 Febbraio 2019
A mathematical billiard is the mechanical system of a point particle traveling in a planar domain subject only to elastic collisions with the boundary of the domain (assumed to be infinitely massive). Systems of this kind have wide application in the physical sciences. I will start by giving a light but mathematically rigorous description of a billiard system, trying to show what features of this description lead to the observed properties of the dynamics (e.g., regular, chaotic, etc.). Ergodic theory is the branch of mathematics that studies the properties of a “dynamical system” from a stochastic/probabilistic point of view. It is the main and perhaps only mathematical tool to study systems, such as chaotic billiards, that admit no exact prediction. I will introduce the most basic notions of ergodic theory, together with some elementary examples of dynamical systems, with a view towards the paradigm of the chaotic billiard.

MECCANICA MACROSCOPICA CON PRESCRIZIONI COSTITUTIVE MICROSCOPICHE
30 Gennaio 2019
Le capacità predittive di ogni modello ingresso-stato-uscita di un sistema dinamico sono condizionate dalle informazioni costitutive relative al sistema modellato. Tipicamente, il punto debole dei modelli della meccanica dei mezzi continui (macroscopica per definizione) è costituito dalla prescrizione costitutiva della tensione. A mio giudizio, questo è dovuto a una specificazione troppo povera dello stato istantaneo del sistema, che si riduce alla coppia (deformazione, velocità di deformazione) di ogni elemento del mezzo. Una cura radicale di questa sindrome consiste nell’associare a ciascun elemento del mezzo continuo un piccolo nugolo di particelle, corredato delle dovute prescrizioni costitutive microscopiche, e di accoppiare in maniera accorta la dinamica macroscopica del mezzo — affrancata da ricette costitutive macroscopiche — con quella dei sistemi discreti di particelle ad esso associati.

COME COSTRUIRE CAMPI DI SFORZO ASSOCIATI A MOTI MOLECOLARI
15 Gennaio 2019
Esporrò una mia versione della procedura di Irving-Kirkwood-Noll per costruire la controparte macroscopica delle interazioni a distanza in un sistema particellare tipico. In particolare, mostrerò che tale controparte, per quel che ne deriva dal meccanismo diffusivo microscopico, si può interpretare come un campo di sforzo analogo a quello associato al nome di Cauchy in meccanica dei continui, mentre la parte che deriva dai moti di fluttuazione si può riguardare come un termine di sorgente nell'equazione di bilancio della quantità di moto.

2018

IL POTERE MULTISCALA DEL CONCETTO DI POTENZA SPESA
5 Dicembre 2018
Le nozioni di potenza spesa in uso in meccanica molecolare e in meccanica dei continui verranno introdotte e commentate. Nessuna delle tre procedure adoperate fin qui per trasferire informazione dalla scala microscopica a quella macroscopica (di Irving&Kirkwood, Hardy-Murdoch e Di Carlo) si è avvalsa dell'ipotesi ragionevole che la potenza spesa, uno scalare invariante, sia considerata un invariante di scala. Di questa ipotesi verranno discusse le conseguenze. Lungo la strada verranno anche presentate brevemente le nozioni collaterali indispensabili per seguire il flusso dell'argomentazione centrale.