Annual report

All the PhD students of the 36th cycle submitted a report on the educational and research activities for admission to the following year. The research topics and scientific production for each PhD student are reported:

- Audisio Lorenzo: During the first year of the PhD I attended Basic courses and Advanced courses provided by the Department of Structural and Geotechnical Engineering, as well as the seminars and conferences in which I participated as a listener, which contributed to my educational growth. I attended 7 basic courses for a total of 25 training credits, 5 advanced courses for a total of 23 training credits, 3 seminars and 6 presentations. During the academic year 2020/2021 I carried out a total of 40 hours of supplementary teaching activity and tutoring in the guided exercises for 3 different Master's Degree Courses at the Faculty of Civil and Industrial Engineering. In summary, I attended a total of 12 courses, 3 seminars, 6 presentations, and carried out 40 hours of supplementary teaching. I also collaborated in the planning and development of two research projects: The MIRRAAL research project and the GENIOSISM research project. In the MIRRAL research project I contributed to the study of the state of the art relating to modular constructions with particular emphasis on structural aspects. I participated in the drafting of the report on the study of the state of the art relating to structural and architectural schemes of Elementary Structural Units and Modular Structural Units, and on the feasibility study of Elementary Structural Units and Modular Structural Units according to the architectural-functional solutions of reference. In the GENIOSISM research project I provided support for the collection of data available at the Ministry of Defense on the building heritage under study and for the identification of the main architectural-constructive and structural characteristics of all the buildings examined, their typological classification and definition of the data model, for the purpose of building a predictive model of seismic risk on a typological basis. In this first year of my PhD I devoted myself to the study of various topics relating to the analysis of the seismic risk of buildings. I studied the topics of interest both by following the courses organized and / or proposed by the Department of Structural and Geotechnical Engineering, and by following the courses held by Prof. Rosario Gigliotti, my supervisor and providing support to the teaching activity. As for my studies, I mainly carried out scientific studies dealt with during the degree and post-thesis thesis, framing these studies in the context of subsequent developments to be carried out during the research doctorate. At the same time, I undertook new studies, as part of the research projects described. The research work begins with a numerical study of the seismic response of existing reinforced concrete buildings, varying the different modeling criteria and capacity models implemented. The study dealt with particular regard to the influence of nodal panel modeling and the phenomenon of sliding in the seismic response of reinforced concrete buildings designed for gravitational loads only. A research work that I have undertaken during this first year of PhD concerns the study of the seismic behavior of non-structural elements. Specifically, through a parametric model developed in OpenSeesPy, I am carrying out comparative analyzes between the literature methods for determining the floor spectra and the formulations recently introduced in the NTC 2018 application circular. frames in the logic of seismic risk together with the theme of modeling of structural elements.

- D'Amore Simone: The proposed theme concerns the study of seismic retrofit interventions of existing buildings in CA through the use of external global interventions with exoskeletons. First of all, the main activity, which continued throughout the year, was a study of the existing literature on these topics. The advantage of using external exoskeletons (frames or partitions) is highlighted by the fact that these can be made from the outside, thus minimally interfering with the usability of the building. Furthermore, the exoskeleton can lend itself to being the support for a second skin of the building, and therefore, the further advantage lies in the possibility of conducting an integrated seismic / energetic / aesthetic intervention. During the first year, one of the fundamental objectives was the definition of an intervention design procedure based on displacements (Displacement-Based Retrofit), specifically designed for frame exoskeletons. The proposed analytical procedure was then validated through the use of static and dynamic non-linear analyzes on models with concentrated plasticity. The effect of the construction technology on the exoskeleton was then investigated, comparing between the monolithic and the low-damage PRESSS system. In particular, the results highlight the advantage of the second, which, being based on hybrid connections, allows the structure to be re-centered following the seismic event. Finally, in the last period more traditional interventions have been studied (ie, the use of FRP, casing of the pillars, etc.) with the aim of comparing the proposed technology with these (widely used in practice), both in terms of safety (life safety index IS-V) and economic (Average Annual Losses, PAM), in order to demonstrate that the proposed technology can lead to an increase in safety and a reduction in losses, as well as having a reduced invasiveness.
Number of courses taken: 15, Number of seminars: 9, Publications in conference proceedings: 1, Conference presentations: 1

- Colatosti Marco: During the first year of my PhD, my research activity was focused on the numerical modeling of composite materials as micropolar continuum. In particular, attention was paid to particle composites characterized by thin interfaces. The work started from the realization of a micro-modeling (discrete model), taken as a benchmark of the problem, of the materials examined, through a finite element model. For the materials, different scales of its internal length were considered, to evaluate their influence on mechanical behavior. In fact, these complex materials have an internal structure (on a nano / micro scale characterized by grains, voids, fibers), whose characteristic size influences the aspects of the medium on a macroscale, such as, for example, its mechanical response. in terms of stiffness, toughness and strength and for this reason they are not easy to represent. However, a very detailed modeling has the drawback of being too expensive from a computational point of view. For this reason, subsequently, we dealt with a comparison with continuous models, both micropolar and classical, of the material itself, obtained through a homogenization technique. The analyzes were conducted both in static and in dynamic conditions, highlighting the advantages of a micropolar description, which is able to take into account the scale of the medium examined and is able to provide an accurate representation of the response of the material. Finally, the work was aimed at the constitutive identification of materials, also considering the more traditional ones, such as, for example, masonry. For this, a subsequent step, exploiting the numerical analyzes carried out, was to test the ability of a genetic algorithm to identify the micropolar elastic constants of the continuous model.
Number of courses, seminars and webinars attended: Courses - 19, Seminars - 4. Number of publications and participations in international conferences: Articles in journals - 4. Number of presentations at conferences: 3

- Fusco Daniela: Given the evident computing power achieved in recent years, scientific and technological innovation is increasingly aimed at the automation of both constructive and evaluative processes. In particular, in the branch of structural monitoring, Structural Health Monitoring (SHM), the application of Artificial Intelligence (AI) is currently being researched. The research work in question aims to respond to the need for more computationally efficient structural models through the development of a high-performance beam model to represent the non-linear behavior of reinforced concrete and prestressed reinforced concrete by including the possible decay. In particular, the work involves the implementation in the OpeenSees software framework of a finite element of beam with the constitutive link of the concrete based on damage and plasticity models. The constitutive formulation chosen for the fiber beam element based on the flexibility approach, force-based approach (FB), is a plasticity and damage model defined by two distinct scalar damage variables, in such a way as to distinguish the behavior by traction and compression of the material. Furthermore, this model allows to take into account the unilateral effect of reclosing the cracks. Regarding plasticity, a Drucker-Prager model was implemented to consider the asymmetric mechanical response of concrete. Furthermore, a simplified regularization formulated specifically for the FB elements and proposed in the literature was adopted. The next step is the modeling of the prestress in the proposed beam element and the effects related to the most frequent pathologies in existing bridges.
Number of courses attended: 9. Number of seminars attended: 5. International conferences: 1. Publications in conference proceedings: 1

- Nela Bledian: The research activity carried out during the first year of PhD studies, as a student of the 36th Cycle at Sapienza University of Rome at Department of Structural and Geotechnical Engineering, is hereby reported. The research has been carried out as part of the Masonry Research Group under the supervision of Prof. Patrizia Trovalusci. The study is focused on Historical Masonry Structures that hold a significant role in the field of Engineering and Architecture and as unique assets of the World Cultural Heritage. Historic Masonry structures are usually formed of large rigid blocks with joints of weak or no mortar. As such they behave nonlinear under even low levels of loading. Although many modeling strategies exist into tackling their simulation problem, the focus of this research is on the plastic theory of limit analysis application to achieve the necessary and sufficient information required for vulnerability assessment, namely the collapse load factor and collapse mechanism. An in-house code ALMA 2.0, within the scope of limit analysis, has been utilized to assess different masonry panels and masonry arches. After enrichment of the code, inclusion of the cohesion parameter has been used to carry a study on masonry reinforcement. By incorporating increased cohesion on the joints as a local reinforcement it was able to assess reinforced masonry arches. Additionally, an upgrading of the code to ALMA 3.0 has been under development to allow the possibility of studying 3D structures as an approach to real-life case studies. Other tools for the modeling of masonry structures have been calibrated such as the FEM software Abaqus, where a discontinuous approach was used to validate and compare results with the limit analysis. Lastly, the design for a new Tilting Table was done which has been produced and placed in the laboratory. This table will be used to test scaled masonry structure subjected to lateral loads that are able to statically simulate the earthquake action.
Curricular Courses Followed (16), Seminars (10), Summer Schools (2), Journal Papers (1), Conference Proceeding (1), Conference presentation (1)

- Salimbeni Michela: The first year of the PhD course in Structural and Geotechnical Engineering (coordinator: Prof. Patrizia Trovalusci) was mainly dedicated to research activity that is part of the seismic risk of plants with danger of major accident (PIR), as defined by Legislative Decree 105/2015. This research activity was also carried out at the INAIL Research Center of the "Department of technological innovations and safety of human plants, products and settlements", located in Rome, Via Torraccio di Torrenova, 7. In particular, bibliographic research was carried out for the definition of the state of the art regarding the evaluation of the seismic risk of industrial equipment, with attention to the case study of an atmospheric tank with a floating roof. With reference to the case study, the dynamics of interaction between fluid and floating roof were studied in depth, both through analytical approaches of literature, and through the use of detailed finite element models, following the identification of the critical elements of the component ( floating roof sealing system). A general methodology has been defined for assessing the seismic risk of industrial equipment, which involves the use of fragility functions aimed at investigating the frequency of occurrence of possible structural and non-structural damage. At the same time, the basic scientific training acquired during the previous academic career was consolidated and expanded, through the attendance of courses provided by the Doctorate and seminars.

- Tropea Giulio Augusto: In a first phase, the behavior of tall structures, in particular with the DiaGrid structure, subject to seismic actions on the basis of classical and innovative approaches, was analyzed in the non-linear field, with the aim of defining new design criteria through a performance-based energy approach. An examination of the existing literature on the subject was conducted to identify the various existing procedures for estimating the input energy and then also assessing the influence of ductility, damping, the hysteretic characteristics of the components on the energy fed into the system. To this end, various techniques have been implemented for estimating the global and partial collapse of tall buildings. A database was also composed with a wide spectrum of experimental test results with different models and seismic signals, including near-fault signals, long duration, and seismic sequences, as well as artificial signals used to calibrate the models and verify the proposed methodologies for the calculation of the hysteretic energy (thanks to the lower number of load cycles they provide simplified bonds forces deformations easier to analyze). Various analyzes were performed on the simple oscillator: pushover, dynamic analysis, IDA, cloud analysis, multi-stripe analyzes. This is in order to have a broad view of the dynamic problem adequately compared with monotonic behaviors. A new metric has been defined to evaluate the seismic capacity of the structures from an energy point of view. This metric has proved effective in representing the capacity of all structural types and different materials (steel, reinforced concrete, masonry). This work has been condensed into an article currently being published in a journal that deals with this metric in detail. Two other works nearing completion analyze the definition of limit states for reinforced concrete and masonry.
Number of courses attended: 16. Number of seminars attended: 7

- Paoloni Alessandra: The proposed research work is aimed at studying and modeling the structural response of historic masonry buildings and innovative reinforcement techniques. The structural behavior, object of the first year study, is described through an equivalent frame model, whose macro-elements consist of a central linear elastic beam with two plastic flexural hinges concentrated at the ends and a distributed shear hinge in series. The non-linear behavior of the masonry assigned to the hinges was initially introduced through an existing hysteresis model based on the formulation of the Bouc-Wen constitutive bond enriched by a scalar damage variable that evolves as a function of the dissipated energy to represent the degradation of resistance and of stiffness, equipped with a parallel device with non-linear elastic behavior to include the effect of pinching and a series device with negative linear elastic behavior due to the high initial stiffness. The existing formulation has been expanded through a second parameter to consider an additional increase in flexibility applied both to the total displacement and to the evaluation of the dissipated energy, to more faithfully reproduce the experimentally recorded behavior of the masonry. The new hinge model was first implemented in the Matlab environment, then within the equivalent frame model in the FEAP finite element program, to insert the formulation of the macro-element in a framework with a "force-based" approach. The solution algorithm has been modified with a procedure for determining the state of the element which allows to condense the deformation residues at the element level within the vector of global residues, avoiding further iterations at the element level. The validation was performed by comparing the results with experimental data found in the literature.
Number of PhD courses attended: 11. Number of other courses and seminars attended: 4. Hours of teaching activity: 35 h

All doctoral students of the 35th cycle submitted a report on the training and research activities for admission to the following year. The research topics and scientific production for each PhD student are reported:

- Damiani Marco: After having studied the problems regarding the use of pultruded cables in composite material such as CFRP (Carbon Fiber Reinforced Polymer) in anchoring systems for Civil engineering applications during the previous PhD year, starting from the first quarter in 2021 we began to study more specific theories for the numerical modeling of FRP materials, which could return more accurate results taking into account the damage of the material. More precisely, the methods studied concern lattice or spring network modeling and microplane modeling. We proceed with the implementation of the latex models of the CFRP cable, under study, in the Abaqus software. Given the particular procedure for building the model, a program has been written in the Python language that returns the calculation model within Abaqus. The constitutive link including damage was provided through Fortran subroutines for Abaqus of type UMAT (for implicit analysis) and VUMAT (for explicit dynamic analysis). Having developed the program for the realization of the latex-type calculation model, we proceed to the numerical simulations of tensile tests on a pultruded cable in CFRP in order to calibrate the mechanical parameters on the basis of the experimental test results available. Furthermore, considered useful for the accuracy of the results to enrich the constitutive link of the elements of the spring network, the shear and bending behavior is added. Analysis for the calibration of the mechanical parameters follows. Experimental tests are identified and planned to be performed on the CFRP cable under study, in order to find useful results to complete the calibration of the numerical models: an experimental setup in steel is designed to be able to perform shear and transverse compression tests on the cable. We then proceed with the implementation of the microplane model of the same CFRP cable element object of the study still in the Abaqus software. The constitutive link of the material, which includes damage, is provided through UMAT-type subroutines.
Number of courses attended: 4. Revised publications / conference proceedings: 2

- De Santis Arturo: The research of the publications and / or writings was carried out and the reconstruction of the theories and the main results of the studies concerning the theme of structural robustness and specifically of progressive collapse in modular structures was carried out. A case study was hypothesized, its functional and distributive characteristics defined and optimized. Safety checks were carried out on the structural elements. The structural analysis was conducted with the modal analysis method and the response spectrum in terms of acceleration for the evaluation of the stress-deformation state induced by dynamic loads (including seismic ones). It was carried out with the finite element method. The systems and related design criteria have been hypothesized to increase the performance of modular constructions against exceptional actions. In particular, the issue of safety against progressive collapse was addressed, increasing the structural robustness of the system starting from the identification of reference scenarios, through two approaches: 1.study of sacrificial elements to compartmentalize the damage and limit the areas of any collapses; 2.study of elements compatible with the modular system and related design criteria to increase the redundancy of the system, without compromising the characteristics of modularity, flexibility and economy, through the possibility of alternative paths of forces (e.g. loss of one or more modules) . The acquired data were analyzed, thus being able to dynamically characterize the structures and verify the effectiveness and robustness of the control system. A model updating was performed, i.e. an improvement in the response of the models to the finite elements and the main results obtained were analyzed. The interests, objectives and planning of the activities to be carried out in the next two years of the PhD have been identified.
Number of courses and seminars attended: 5

- Destro Bisol Giacomo: The second year of the doctorate was dedicated to: (a) training through courses and seminars (for a total of five); (b) training through self-study; (c) teaching support activities; (d) development of the doctoral thesis; (e) production of journal articles (one published and one currently under review). the goal of the doctoral thesis is the formulation of multi-body models capable of describing the dynamic behavior of this structural type (such as, for example, the statue-pedestal system or the vertical bending mechanism for masonry walls). In this year the work carried out was: a) formulation of the equations of motion for the model formed by two rigid blocks on a seismic isolator c) formulation of the threshold accelerations for which the triggering of the oscillatory motion occurs c) formulation of the accelerations of threshold for which there is a change of configuration d) formulation of a MatLab code capable of describing the motion of the system and of all the phenomena that it can undergo, such as impacts. The equations of motion have been formulated through a Lagrangian approach and implemented in the MatLab environment, where an event-based strategy has been formulated to capture all the possible phenomena that the system can undergo during motion.

- Ferreira Martins Juliano: The activities performed on the second year were mainly related to the development of the main feature of my PhD project. All activities that were developed through the year were in accordance with the Supervisor and the co-Supervisor. The topic of my research is the development of a piezoelectric device connecting the bracing members to the rest of the structure, for energy harvesting (EH) purposes on wind-excited steel buildings. The design of this device which is called PiD were investigated throughout this year by FEM analysis on the ANSYS software. The product is a working non-linear 3D FEM model of the piezoelectric energy harvesting device where the input is the time history displacement at its boundary as induced by a connected bracing element and extracted from a global building model. The output is the time history of the displacement of the inner piezo parts of the PiD, to be used as input in a different FEM model implementing piezo mechanical features to have the final product which is the harvested energy. To synthesize the activities of this year we can divide it on: Strengthening of basis (focused on literature review), Conceptual design of PiDs (modelling and analysis attributes), Courses and seminars followed (2 courses, and two summer school all on online mode) and the Development of the research, which was mainly concentrated on the developing of a phase where it is called: design of the PiD device. This PiD is the portion of piezoelectric, and it is addressed as the main equipment for obtaining the final result of the work. One of the product to be observed is the analysis of the harvested energy and the influence of such equipment when attached to the building model.

- Khanistan Said Jalal: This year, in addition to the literature review of the post-seismic surveys and experimental works on the out-of-plane response of infill walls, we conducted numerical studies on three different types of multi layered walls, to obtain optimum system of infill walls in terms of energy efficiency. Moreover, we developed recycled-plastic joints to increase the out-of-plane ductility of infill walls. Optimizing Out-of-plane Response of infill panels: To increase the out-of-plane ductility of infill panels, we worked on joints made of recycled plastics. To model the geometry of the proposed joints SolidWorks was used. COMSOL Multiphysics, was used to optimize the shape and typology of the joints. COMSOL Multiphysics was also used to perform buckling analyses of the joints. The optimally sized and shaped joint, then, was imported into slicing software Ultimaker Cura. Then, was printed by 3D printing technology. The recycled plastic material such as: Polypropylene (PP) and Polylactic Acid (PLA) are reasonable candidates for producing the joints. Polypropylene while being more ductile is our first choice. The infill panels will be assembled by placing the above mentioned plastic joints, within the blocks of clay, concrete or bricks. Each joint is made of two, three dimensional parts, fixed into each other to make a single joint. The plastic joints will be located, in transverse direction throughout the infill panels, in different locations. The joints are connected by two horizontal connectors to the outer and inner layers of the multi-leaf walls respectively. Thermal Analyses: To optimize thermal behavior and energy efficiency, we optimize the three types of multi leaf infill walls proposed by Monti and Vailati (2018), reported in the following table. We modeled the proposed three types of wall panels using COMSOL Multiphysics and then conducted analyses of heat transfer. By changing the thickness of the layers we obtain the optimum configuration of the walls, which can save maximum energy, while being energy efficient and resistant to fire.

- Novelli Francesco: In the first quarter, the numerical experimentation activity with the EF Abaqus / Standard code began. In particular, the implementation philosophy in the code of an advanced constitutive model for unsaturated soils (WR2-Unsat model) was studied in detail by means of the relative UMAT routine. In the second quarter, the numerical activity, conducted with the above model, had as its object a parametric study whose main purpose was to evaluate the influence of the properties of the material and of the initial state conditions on the occurrence or otherwise of hydro-mechanical instability conditions in unsaturated soils during imbibition paths. Some analytical results were achieved in the third quarter. In particular, a criterion proposed for mechanical disturbance only (compression) has been extended to the case of hydraulic perturbation (imbibition). Furthermore, a theoretical justification has been provided for this criterion, extending also in this a previous work of literature.
In the fourth quarter, the experimental activity began at the Geotechnical Laboratory of the University of Campania "Luigi Vanvitelli". During this period, some preliminary activities were carried out for the experimentation, such as the calibration of part of the instrumentation relating to the equipment used. The laboratory activity, still in progress, is carried out on the volcanic ashes collected at the sample site of Cervinara (AV) and will have the purpose of determining some properties of the material required by the particular constitutive model adopted. In this way it will be possible to calibrate the model and verify the occurrence or not, in this terrain, of the instability conditions observed numerically in the parametric study.
Courses and seminars attended: 6

- Pedone Livio: The research topic dealt with concerns the evaluation of the safety and economic losses of reinforced concrete buildings in pre- and post-earthquake scenarios. During the second year of the PhD, the research activity involved, in a first phase, an in-depth and continuous study of the scientific literature on the research topic. A study was then conducted on the possibility of carrying out an extension of the Simple Lateral Mechanism Analysis (SLaMA) procedure for buildings in post-earthquake conditions (i.e., damaged by the earthquake). To this end, we proceeded with the implementation of the SLaMA analytical procedure in Python programming language, and the possibility of implementing an extension of the procedure was investigated that would allow a more accurate estimate of the initial stiffness of the structure to be obtained. In addition, a study was conducted on the possibility of developing a simplified method for obtaining fragility curves depending on the state of damage. This research activity was carried out during a 6-month study period abroad at the Hosting Institution University College London (UCL), under the external supervision of Prof. C. Galasso. In particular, a simplified framework was proposed, based on the use of non-linear static analyzes combined with the Cloud-Capacity Spectrum Method. The achievement of a specific level of damage is simulated through suitable reduction coefficients for the structural elements in terms of stiffness / strength / ductility. The preliminary results showed that the percentage error obtained by comparing the proposed framework with a more refined analysis (i.e., non-linear dynamic analyzes) is contained in the order of 20%. The framework can be used to carry out future probabilistic analyzes of seismic risk and assessment of expected economic losses in pre- and post-earthquake scenarios.
Number of PhD courses attended: 6. Number of seminars / webinars attended: 11. Number of publications in conference proceedings: 3. Number of presentations given in conferences: 2.
Research period abroad lasting 6 months (1/05 / 2021-31 / 10/2021) at the Hosting Institution University College London (UCL), under the external supervision of Prof. Carmine Galasso

- Rosati Alessandra: The activities of the second year of the PhD were aimed at preparing the knowledge and skills base necessary for the development of a numerical study aimed at investigating the operating behavior of suction caissons used as anchoring systems for offshore floating platforms and installed in normal consolidated fine-grained soils. The activities carried out can be summarized in: (i) study of modeling techniques for typical problems of geotechnical engineering, with particular reference to underground foundations, in the Abaqus / Standard finite element code; (ii) study of advanced constitutive bonds for fine-grained soils; (iii) study of the scientific literature available on the subject of suction caissons used in Offshore Engineering applications. Subsequently, an axial symmetric finite element numerical model was developed in the Abaqus / Standard calculation code for the modeling of suction caissons immersed in a homogeneous layer of soft clay and subjected to vertical and centered tensile loads. The model was used to reproduce some literature results deriving from numerical and experimental studies. In carrying out these activities, two informal meetings with Prof. Mark Randolph and his research group from the University of Western Australia (UWA) were of great use for possible further research. Finally, during the year, the following were drafted: (i) the Project Launching University Research 2021 entitled "A macro-element model for suction anchors of floating offshore platforms", for which 1500 euros were financed; (ii) the 2021 University individual mobility project, entitled "Analysis of the Response Of Suction Anchors in soft clay for offshore floating platforms", for which 4200 were funded to be used for a stay as a visiting PhD student at UWA, Perth, Australia.
Number of courses / seminars attended a.y. 2021-2021: 7. Number of publications in conference proceedings accepted a.y. 2021-2021: 1. Number of hours of supplementary teaching activities a.y. 2021-2021: 40

All the PhD students of the 34th cycle presented a report on the training and research activities for admission to the final discussion. The research topics and scientific production for each PhD student are reported:

- Ciurlanti Jonathan: During the last year of my PhD I finalized my research work on the subject of the integrated performance of reinforced concrete buildings, including the study of architectural elements and internal contents. During the first trimester I carried out research activities focusing on parametric and probabilistic analyzes. During development, I then began to conceptualize a python algorithm that would give the possibility to flexibly parameterize buildings of different geometry and materials, and by communicating with different APIs (application programming interfaces), the possibility of carrying out numerical analyzes using technical software ( eg energyplus). The conceptualization of the workflow took place during my stay abroad at Arup where, subsequently, I returned to develop it further. Subsequently I worked on the drafting and development of research projects and various deadlines related to scientific contributions for conferences (Compdyn 2021, fib young symposium). In the first months of 2021, the work of drafting the thesis also began, starting with the introductory and state of the art chapters. In the second period in Arup I then refined my knowledge of scientific implementation through courses such as "Advanced Javascript Training" but also optimization methodologies through the "Introduction to LS-Opt" course. I also developed the python workflow and subsequently used it for the work in my thesis. During the following months I participated in two conferences as a speaker: Compdyn 2021 and 17th World Conference of Earthquake Engineering. In the final months I mainly dealt with the writing of the final dissertation (doctoral thesis, 396 including appendices).
Number of seminars and courses attended: 4. Number of conferences: 2. Number of publications: 4

- Di Giovanni Giulia: During the last year of my PhD, I completed the critical analysis of the state of the art concerning the subject of the thesis, that is the Mobile Facade (FM) systems - monolithic and multi-block - used for the reduction of vibrations induced in tall buildings by horizontal actions (wind, earthquake and exceptional actions). I continued the Research activity aimed at solving the problem of large façade displacements. For this purpose, exploring the field of nonlinear dynamics, I studied several proposals for structure-facade connection devices that use high dissipation materials. For each typology I have qualitatively identified the design parameters and the respective spatial intervals for the purpose of carrying out the nonlinear dynamic parametric analyzes. I developed the FM connection technological project through the conception and numerical modeling of friction devices integrated with a system of shock absorbers for the mitigation of the structural and facade response. The preliminary evaluation phase concerned the performance of monolithic FM with dissipative connection applied on a typical 77m building modeled at 2-degrees of freedom (g.d.l.) under harmonic excitation. Subsequently, I applied the multi-block FM system with dissipative connectors on the Isozaki tower in Milan, taken as the main case study, in order to evaluate the effectiveness of the devices proposed on an existing high building (220m) in a more realistic wind scenario. I modeled the building with FM a plus-g.d.l. subjecting it to a turbulent wind load calculated according to CNR-DT 207/2008 and simulated with the Monte Carlo method in the NatHaz Online Wind Simulator (NOWS) platform. At the same time, I dedicated myself to the drafting of the final paper, reporting in the thesis all the results achieved in the context of my research activity.
Number of seminars / courses attended in the last year: 12. Number of publications in the last year: 2 under review

- Francioli Mattia: The research activity is focused on some of the aspects that emerge for a structural problem in the Multi-Hazard context. The first issue addressed is related to the unification of the language with which the structural performance for the various hazards is evaluated and expressed, with specific reference to wind and earthquake. Since these are two natural hazards and characterized by well-defined statistics, the approach used is probabilistic; the well-known SAC-FEMA analysis methodology in the seismic field has been extended to the case of wind, in order to evaluate the performance with a unified procedure and express it using the same metrics (for the two hazards considered) and with the aim of quantifying the annual mean frequency (MAF) with which a given LS limit state occurs. The performance of the steel frames with different heights under wind and seismic hazard was then evaluated in the view of the considered ULS and SLS, in order to determine the relative importance of the different hazards in the structural response of this type of structures. In this way, a further problem relating to multi-hazard design has been implicitly addressed, the one relating to conflicting design strategies. Another aspect addressed regarding the structural problem in the Multi-Hazard context is the interaction between different hazards, specifically the so-called Hazard-chain for Low Probability-High Consequences events. These are characterized by very low probability of occurrence and thus a scenario approach has been used. The seismic event was considered as the main event and an explosion, caused by the damage due to the earthquake, as a chained event. The effects of the change in structural vulnerability following the concatenation of events are evaluated in terms of structural robustness, using the so-called "blast-scenario dependent robustness (BSR) curves", which take into account the parameters of the specific blast hazard, (blast intensity and impulsive rate).
Number of courses taken: 1. Number of conference presentations: 1. Journal publications and conference proceedings: 4.

- Gallese Domenico: The research activity carried out during the third year of the PhD has provided practical indications for the seismic sizing of integral bridges, focusing attention on a particular static scheme, with a single span, of rather frequent use in our country. The study makes use of the development of three-dimensional models of different complexity developed in the OpenSees environment, on which non-linear dynamic analyzes are carried out. The results of these analyzes are reproduced by means of simplified interpretative schemes, which suitably generalized and systematized can be used as design methods for similar works. This research was summarized in the doctoral thesis entitled: "Soil-structure interaction for the seismic design of integral abutment bridges: from advanced numerical modeling to simplified procedures" currently under review by two external professors (one Italian and one international). Parallel to the work of the doctoral thesis, I collaborated with prof. Pedro Arduino (University of Washington) regarding the development of the "embedded element" in the OpenSees environment. The study of this element represents my main activity at the University of Washington (Seattle WA) where I went from 24 September to 31 December 2021 as a "visiting PhD student" under the supervision of prof. Pedro Arduino. The research focused on the implementation and extension of this element which had previously been developed by the research group of the University of Washington. Numerous numerical analyzes were performed in order to validate different geometric and load conditions (transverse and vertical), different hypotheses of pole-ground contact and the influence of the poles in the group. From a practical point of view, the benefit of using this element substantially allows the generation of the ground mesh to be released from the presence of structural elements through appropriate mapping laws imposed on the pole-ground interface surface, with great advantage from the point. computationally. This work will be followed by publications currently being written. During this period I also attended courses at the same university aimed at deepening my knowledge on geotechnics and object-oriented programming. Finally, I held a seminar in attendance at the University of Washington entitled "Nonlinear static analysis for integral abutment bridges: from advanced numerical modeling to simplified procedures" for master's degree students and for professors in the Department of Civil and Environmental Engineering.
Seminars and courses attended: 8. Publications: 2 articles in an international journal (currently under review); 2 conference papers (one of which is international and one is Italian)

- Kareemi Muhammad Ajmal: Review of a set of different code provisions around the world regarding current code-based formulations for the shear capacity assessment of RC beams and columns is represented. A new shear capacity equation is developed that accounts for the shear mechanism of TTP beams. The theoretical framework of the variable-angle strut theory, largely adopted in many Codes, including NTC-2018 and EN 1992 has been preferred to others, possibly even more accurate, because of its mechanics-based approach, which facilitate the extension to a different beam configuration. Calibrating a suitable value for the model uncertainty factor \gamma_{Rd} in the code-formatted equation, by adopting the Design-by-Testing approach of EN 1990, Annex D, whereby the predictions offered by the code-calibrated equation have been compared with the experimental results available in the literature and those carried out by the candidate. EN 1990 calibration approach has been reviewed and modified to simplify its application, while retaining its reliability. The simplified procedure has been applied to the calibration of the model partial factor for both the Eurocode shear equation, adapted to the case of TTP beams, and the proposed equation. The study is finally concluded by an application of the newly developed code-calibrated shear capacity equation. It refers to the optimized design of TTP beams, considering different spans and different phase II / phase I loads ratios. The developed equations allow obtaining optimized TTP beams where both Phase I and Phase II safety requirements are effectively fulfilled.
Number of courses attended: 3

- Kazemi Majd Foad: Investigation the damage identification by machine vision for the defect recognition technique from the data’s interpretation of the bridge’s images. Reviewing the traditional method of bridge inspection includes the visual and physical activities of the various elements, also Non-destructive testing (NDT) recognizes the defects for infrastructure with advantage and disadvantage characteristics according to damage classification. Simulating the defects and relative Non-Destructive Testing (NDT) by ANSYS MAXWELL & COMSOL of Quisi (railway) steel truss bridge. Writing the outcome of the chapter “eliminates the routine inspection schedule through the predict the defects and FEM analysis. Obtaining the result of K-mean clustering to detect different types of corrosion in the portion of images by Matlab R2021a for the paper “Detection of corrosion defects in steel bridges by machine vision” for the conference of EUROSTRUCT2021 (European Association on Quality Control of Bridges and Structures) in University of Padova. Finishing the writing of chapter’s thesis “Inspection & maintenance for infrastructure that included the destructive & nondestructive techniques (VT [Visual Testing], MT [Magnetic Testing], PT [Penetrating test], RT [Radiographic test], UT [Ultrasonic test])”. Preparing the presentation “Image based corrosion detection of steel bridge by computer vision” for AIVELA conference in DIISM (Università Politecnica delle Marche).
Numero di seminari e corsi seguiti: 3. Numero di conferenze:2. Numero di pubblicazioni: 1

- Marchi Andrea: The candidate has concentrated his research work on the dynamic analysis in the seismic field of bridges with integral abutments. In particular, he has developed a two-dimensional dynamic non-linear finite element numerical model for the evaluation of the dynamic response to seismic signals, taking into account the local seismic response of the site and the soil-structure interaction through non-linear Winkler elements. A comparison work was also carried out on this model with a continuous three-dimensional model with nonlinear constitutive links for the land developed, within the department, by Domenico Gallese and Professor Callisto as part of the doctoral thesis of Eng Welsh. Subsequently, the candidate also extended the two-dimensional finite element computation model to the three-dimensional case in order to evaluate the contribution of the transverse response in the overall behavior of the structure. On these non-linear dynamic models, parametric and sensitivity analyzes are underway for the various input parameters. Taking the dynamic model as a reference, simplified static models were also studied for the pre-dimensioning and design of such works. These models (dynamic and static) were used within the ReLUIS-RINTC project in order to design and analyze integral shoulder overpasses in three sites in the Italian territory (Milan, Naples and L'Aquila, respectively representative of low, medium and high seismicity). These works were designed using simplified non-linear static models in SAP2000 and subsequently analyzed in the context of a "stripe" analysis using non-linear dynamic models (two-dimensional and three-dimensional) using the OpenSEES software. These strip analyzes will then be used to study the seismic risk of these works (designed according to legislation) on the Italian territory. The study of these simplified models also served as an aid for the rewriting of Eurocode 8 part 2 (in the sections concerning the design of integral bridges. safety for the new resistance models of reinforced concrete elements proposed by Biskinis and Fardis, both for compliant and non-compliant elements. In particular, with regard to yield rotation, ultimate rotation and shear strength of vertical elements in Furthermore, the calculation of the partial safety factors was also carried out for the resistance formulas in the seismic field for steel elements, both new and existing (and therefore not compliant with the regulations).
Number of articles in conference proceedings: 1

- Salvatore Andrea: The research activity carried out during the third year of the doctorate was aimed at deepening the proposed research topic and at the conclusion of the writing of the doctoral thesis. In particular, the analytical study of the multidirectional dissipator with negative stiffness and superelastic hysteresis (subject of the thesis) was carried out and the hysteretic law governing the force-displacement bond was identified. Furthermore, by simplifying the analytical equations, compact formulas representative of the macro quantities characterizing the heat sink and useful in the pre-sizing and design phase have been obtained. Subsequently the project of the prototype in scale was developed and the executive drawings were drawn up aimed at the realization of the prototype. At the same time, the numerical study of the dynamic response of a system with several degrees of freedom was carried out, representative of a building isolated at the base by means of elastomeric supports, subject to seismic forcing and controlled by negative stiffness and superelastic hysteresis. The optimal configurations of the proposed damping system were determined under different requirements and objectives. Finally, the performances obtained with the proposed damping system were compared with those exhibited by the classic damping systems (viscous, hysteretic, attractive, hybrid) optimized with the same criteria.
Number of courses / seminars attended during the third year of the doctorate: 3. Number of journal publications during the third year of the doctorate: 2. Number of conference presentations during the third year of the doctorate: 2

- Talebi Aliasghar: The main focus of my research on the last academic year, based on the thesis topic, was trying to find an efficient approach for vibration-based finite element model updating, using optimization techniques. Particle Swarm Optimization has been used for the studied approach and the method is based on the search of possible modifications in stiffness and mass matrices of elements. The other part of the study concerns the integration of BIM and FEA and the use of the BIM model in the updating procedure. Considering the inevitability of collaboration between BIM and structural analysis, the proper transferring of the data from BIM to FEA and realizing the best possible mesh type seems necessary. Furthermore, vibration data as an input in this procedure need to be analyzed. The dynamic identification of the structure using vibration data in time series by two techniques of SSI and PolyMAX was the other part of the study. Finding a way to implement the data in the BIM model was a part of the effort of monitoring and dynamic identification in the BIM environment. The final part of the research is concerning damage detection using the suggested algorithm for model updating by PSO and still is in progress. The research activities of the last year, in general, were focused on the finite element model updating using 1D, 2D, and 3D elements from the BIM model, model updating by PSO, integration of BIM and FEA and monitoring, and finally an effort toward the damage detection in BIM using the suggested algorithm. The number of attended seminars in the Academic year 2020-2021, which was the third year of the Ph.D. study of the 34th cycle, was 8 seminars and 3 courses. No accepted paper yet but one paper submitted for the Computers and Structures journal.

- Zahedin Labaf Daniele: The research activity is framed within the passive control of vibrations of structures excited at the base. In particular, its primary objective is the study of a new structural control system, called hybrid, which combines the advantages of base insulation with those of an innovative tuned mass system, known in the literature as TMDI, which involves the use of an Inerter: a mechanical device, whose potential is still little explored in Civil Engineering, capable of developing a force proportional to the relative acceleration between its terminals. The research activity was aimed at filling this gap, paying particular attention to the possibilities of use in the reduction of the seismic response of tanks for the storage of liquids, located in factories, framed by current legislation as at Risk of Major Accident. The activity is structured along two lines: theoretical and experimental. On the first front, simplified models have been developed, depending on a limited number of parameters to describe the dynamics of the system under control. The optimal design of the hybrid control system was therefore addressed through the use of simplified inputs and the evaluation of dynamic response, effectiveness and robustness. The selection of seismic inputs took place with particular attention, considering far-field, near-fault and long-period actions, whose influence on the dynamic response was evaluated. The results obtained were subjected to performance comparison with Literature solutions. On the experimental front, the feasibility study of a small-scale physical model of a tank equipped with a hybrid control system to be tested on the vibrating table at the Materials and Structures Testing Laboratory of the Department of Structural and Geotechnical Engineering was implemented.
Seminars: 2; Courses attended: 2; Publications: 1;

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