Modelling and analysis of internally BFRP reinforced beams at elevated temperatures

The aim of the work is to conduct a finite element model analysis on a small – size concrete beam and on a full size concrete beam internally reinforced with BFRP exposed at elevated temperatures. Experimental tests performed at Kingston University have been used to compare the results from the numerical analysis for the small – size concrete beam. Once the behavior of the small – size beam at room temperature is investigated and switching to the heating phase reinforced beams are tested at 100°C, 200°C and 300°C in loaded condition. The aim of the finite element analysis is to reflect the three – point bending test adopted into the oven during the exposure of the beam at room temperature and at elevated temperatures. Performance and deformability of reinforced beams are straightly correlated to the material properties and a wide analysis on elastic modulus and coefficient of thermal expansion is given in this work. Develop a good correlation between the numerical model and the experimental test is the main objective of the analysis on the small – size concrete beam, for both modelling the aim is also to estimate which is the deterioration of the material properties due to the heating process and the influence of different parameters on the final result. The focus of the full – size modelling which involved the last part of this work is to evaluate the effect of elevated temperatures, the material deterioration and the deflection trend on a reinforced beam characterized by a different size. A comparison between the results from different modelling has been developed.

Climatological analysis of temperature and salinity fields in the Mediterranean sea

A climatological field is a mean gridded field that represents the monthly or seasonal trend of an ocean parameter. This instrument allows to understand the physical conditions and physical processes of the ocean water and their impact on the world climate. To construct a climatological field, it is necessary to perform a climatological analysis on an historical dataset. In this dissertation, we have constructed the temperature and salinity fields on the Mediterranean Sea using the SeaDataNet 2 dataset. The dataset contains about 140000 CTD, bottles, XBT and MBT profiles, covering the period from 1900 to 2013. The temperature and salinity climatological fields are produced by the DIVA software using a Variational Inverse Method and a Finite Element numerical technique to interpolate data on a regular grid. Our results are also compared with a previous version of climatological fields and the goodness of our climatologies is assessed, according to the goodness criteria suggested by Murphy (1993). Finally the temperature and salinity seasonal cycle for the Mediterranean Sea is described.

Analysis, modelling and design of a groin as coastal protection structure at Lido di Dante, Ravenna

An analysis and a subsequent solution is here presented. This document is about a groin design able to contrast the erosion actions given by waves in Lido di Dante. Advantages will be visible also for Fiumi Uniti's inlet, in the north side of the shoreline. Beach future progression and growth will be subjected to monitoring actions in the years after groin construction. The resulting effects of the design will have a positive impact not only on the local fauna and environment, but also, a naturalistic appeal will increase making new type of tourists coming not only for recreational purposes. The design phase is focused on possible design alternatives and their features. Particular interest is given to scouring phenomena all around the groin after its construction. Groin effects will impact not only on its south side, instead they will cause an intense erosion process on the downdrift front. Here, many fishing hut would be in danger, thus a beach revetment structure is needed to avoid any future criticality. In addiction, a numerical model based on a generalized shoreline change numerical model, also known as GENESIS, has been applied to the study area in order to perform a simplistic analysis of the shoreline and its future morphology. Critical zones are visible in proximity of the Fiumi Uniti's river inlet, where currents from the sea and the river itself start the erosion process that is affecting Lido di Dante since mid '80s, or even before. The model is affected by several assumptions that make results not to be interpreted as a real future trend of the shore. Instead the model allows the user to have a more clear view about critical processes induced by monochromatic inputed waves. In conclusion, the thesis introduce a wide analysis on a complex erosion process that is affecting many shoreline nowadays. A groin design is seen as a hard solution it is considered to be the only means able to decrease the rate of erosion.

The italian translation of allusive jokes from three american sitcoms: A focus group analysis

The translation of allusions has presented an issue for translators, in a trend that has seen a shift in translation studies to a more culture-oriented perspective. “Allusion” is defined by doctor Ritva Leppihalme as a culture-bound element that is expected to convey a meaning that goes beyond the mere words used and can only be accurately translated through knowledge of both the source and target culture. Allusions in comedy, and more specifically, allusive jokes, can pose an additional challenge to translators, since failing to translate them in a satisfactory way, can lead to unfunny and puzzling results that completely miss the original comedic value of the allusion itself. For the purposes of this dissertation, an experiment, based on the one done by doctor Ritva Leppihalme, was conducted: a focus group consisting of eight people from different socio-demographic groups was asked to discuss three comedic scenes, translated in Italian, containing an allusive joke, from three different American sitcoms: Community, The Office, and Superstore. The purpose of this research was to find the best and most effective strategies, according to the average Italian viewer, to translate in Italian allusive jokes from the American culture and the English language. The participants were asked to state if they understood the translated joke, and if they did, to rate how funny they found it, and to discuss among themselves on possible reasons for their responses, and on possible alternative solutions. The results seem to indicate that the best course of action involves choices that stray from a literal translation of the words used, by changing items that need a deeper knowledge of the source culture to be understood and therefore cause hilarity, with items more familiar to the target culture. The worst possible solutions seem to be ones that focus on the literal translation of the words used without considering the cultural and situational context of the allusion.

Root cause analysis applied to a finite element model's refinement of a negative stiffness structure

Negative Stiffness Structures are mechanical systems that require a decrease in the applied force to generate an increase in displacement. They are structures that possess special characteristics such as snap-through and bi-stability. All of these features make them particularly suitable for different applications, such as shock-absorption, vibration isolation and damping. From this point of view, they have risen awareness of their characteristics and, in order to match them to the application needed, a numerical simulation is of great interest. In this regard, this thesis is a continuation of previous studies in a circular negative stiffness structure and aims at refine the numerical model by presenting a new solution. To that end, an investigation procedure is needed. Amongst all of the methods available, root cause analysis was the chosen one to perform the investigation since it provides a clear view of the problem under analysis and a categorization of all the causes behind it. As a result of the cause-effect analysis, the main causes that have influence on the numerical results were obtained. Once all of the causes were listed, solutions to them were proposed and it led to a new numerical model. The numerical model proposed was of nonlinear type of analysis with hexagonal elements and a hyperelastic material model. The results were analyzed through force-displacement curves, allowing for the visualization of the structure’s energy recovery. When compared to the results obtained from the experimental part, it is evident that the trend is similar and the negative stiffness behaviour is present.

Magnetic field in the outskirts of PSZ2 G096.88+24.18 from depolarization analysis of radio relics

Radio relics are one of the different types of diffuse radio sources present in a fraction of galaxy clusters. They are characterized by elongated arc-like shapes, with sizes that range between 0.5 and 2 Mpc, and highly polarized emission (up to ∼60%) at GHz frequencies The linearly polarized radiation of relics, moving through a magnetized plasma which is the ICM, is affected by the rotation of the linear polarization vector. This effect, known as “Faraday rotation”, can cause depolarization. The study of this effect allows us to constrain the magnetic field projected along the line of sight. The aim of this thesis work is to constrain the magnetic field intensity and distribution in the periphery of the cluster PSZ2 G096.88+24.18: this cluster hosts a pair of radio relics that can be used for polarization analysis. To analyse the polarization properties of the relics in PSZ2 G096.88+24.18 radio relics we used new Jansky Very Large Array (VLA) observations together with archival observations. The polarization study has been performed using the Rotation Measure Synthesis technique, which allows us to recover polarization, minimizing the bandwidth depolarization. Thanks to this technique, we recovered more polarization from the southern relic (with respect to provious works), We studied also the depolarization trend with the resolution for the southern relic, and found that the polarization fraction decreases with the beamsize. Finally, we have produced simulated magnetic fields models, varying the auto-correlation lengths of the magnetic field, in order to reproduce the observed depolarization trend in the southern relic. Comparing our observational results and model predictions, we were able to constrain the scales over which the turbulent magnetic field varies within the cluster. We conclude that the depolarization observed in the southern relic is likely due to external depolarization caused by the magnetized ICM distribution within the cluster.