No presente trabalho apresenta-se um estudo de caso com auxílio de uma metodologia sistemática para aplicação de métodos estruturados ao desenvolvimento de novos produtos em uma indústria do ramo de implementos rodoviários. Considerando os implementos rodoviários como produtos industriais, pretende-se trabalhar as formas e processos de criação e aperfeiçoamento na geração de idéias e busca por soluções até a fase do projeto final de um novo produto. Também, foram considerados os processos de fabricação, modelamento do produto, e análises estruturais numéricas, que são ferramentas de auxílio na otimização do produto final. Paralelamente, foram consideradas as informações dos testes experimentais para auxiliar e validar as análises estruturais numéricas, contribuindo desta forma para o aperfeiçoamento de requisitos na fase do projeto de produto, antes de sua fabricação e lançamento no mercado. Assim, este estudo apresenta como foco o desenvolvimento de um semi-reboque para transporte de cana picada, com o intuito de exemplificar e aplicar de forma prática as ferramentas estudadas e seus respectivos usos no produto em questão. Os testes de campo foram instrumentados com sensores extensométricos resistivos para coleta de dados de níveis de tensão e posterior comparação com as análises numéricas. Os dados do produto, na fase de testes experimentais, foram obtidos em condições reais de trabalho junto a uma usina do setor sucro alcooleiro. Finalmente, considerando-se os resultados de desempenho do produto, semi-reboque rodotrem para transporte de cana picada, pode-se identificar que o uso de uma metodologia de referência para o desenvolvimento de produto, apoiada por ferramentas de análise estrutural, com testes de campo instrumentados, são confiáveis e úteis aos profissionais da engenharia de projeto e manufatura. / In this paper work, a case study using a systematic methodology is presented to apply structured methods for designing new products in an industry of road implements field. Considering the road implements as industrial products, it is intended to deal with forms and processes of developing ideas and improving the generating of ideas and quest of solutions until the final phase project of a new product. The manufacturing process will also be taken into consideration, besides the modeling of the product and numerical structural analysis which are tools to help optimize the final product. In addition, will be taken in considerations the information of experimental tests to avail and validate the numerical structural analysis, and through it contribute to the improvement of requirements during the design of the product before its manufacture and market launch. This study presents the development of a semi-trailer to transport chopped sugar cane, with the purpose of exemplify and put on practice the tools which are studied and their uses applied in the product concerned. The field tests were instrumented with strain gage sensors to collect data on tension levels for later comparison to numerical analysis. This way, it is expected to have reliable data as the product will operate in a plant following through real work situations during these experimental tests. Finally, considering the results of product performance - road train semi-trailer to transport chopped sugar cane - can be identified in this study that the use of a method of reference to product development, supported by structural analysis tools, and instrumented field tests are reliable and extremely useful to the professional activities of design and manufacturing engineering.

No presente trabalho apresenta-se um estudo de caso com auxílio de uma metodologia sistemática para aplicação de métodos estruturados ao desenvolvimento de novos produtos em uma indústria do ramo de implementos rodoviários. Considerando os implementos rodoviários como produtos industriais, pretende-se trabalhar as formas e processos de criação e aperfeiçoamento na geração de idéias e busca por soluções até a fase do projeto final de um novo produto. Também, foram considerados os processos de fabricação, modelamento do produto, e análises estruturais numéricas, que são ferramentas de auxílio na otimização do produto final. Paralelamente, foram consideradas as informações dos testes experimentais para auxiliar e validar as análises estruturais numéricas, contribuindo desta forma para o aperfeiçoamento de requisitos na fase do projeto de produto, antes de sua fabricação e lançamento no mercado. Assim, este estudo apresenta como foco o desenvolvimento de um semi-reboque para transporte de cana picada, com o intuito de exemplificar e aplicar de forma prática as ferramentas estudadas e seus respectivos usos no produto em questão. Os testes de campo foram instrumentados com sensores extensométricos resistivos para coleta de dados de níveis de tensão e posterior comparação com as análises numéricas. Os dados do produto, na fase de testes experimentais, foram obtidos em condições reais de trabalho junto a uma usina do setor sucro alcooleiro. Finalmente, considerando-se os resultados de desempenho do produto, semi-reboque rodotrem para transporte de cana picada, pode-se identificar que o uso de uma metodologia de referência para o desenvolvimento de produto, apoiada por ferramentas de análise estrutural, com testes de campo instrumentados, são confiáveis e úteis aos profissionais da engenharia de projeto e manufatura. / In this paper work, a case study using a systematic methodology is presented to apply structured methods for designing new products in an industry of road implements field. Considering the road implements as industrial products, it is intended to deal with forms and processes of developing ideas and improving the generating of ideas and quest of solutions until the final phase project of a new product. The manufacturing process will also be taken into consideration, besides the modeling of the product and numerical structural analysis which are tools to help optimize the final product. In addition, will be taken in considerations the information of experimental tests to avail and validate the numerical structural analysis, and through it contribute to the improvement of requirements during the design of the product before its manufacture and market launch. This study presents the development of a semi-trailer to transport chopped sugar cane, with the purpose of exemplify and put on practice the tools which are studied and their uses applied in the product concerned. The field tests were instrumented with strain gage sensors to collect data on tension levels for later comparison to numerical analysis. This way, it is expected to have reliable data as the product will operate in a plant following through real work situations during these experimental tests. Finally, considering the results of product performance - road train semi-trailer to transport chopped sugar cane - can be identified in this study that the use of a method of reference to product development, supported by structural analysis tools, and instrumented field tests are reliable and extremely useful to the professional activities of design and manufacturing engineering.

No presente trabalho apresenta-se um estudo de caso com auxílio de uma metodologia sistemática para aplicação de métodos estruturados ao desenvolvimento de novos produtos em uma indústria do ramo de implementos rodoviários. Considerando os implementos rodoviários como produtos industriais, pretende-se trabalhar as formas e processos de criação e aperfeiçoamento na geração de idéias e busca por soluções até a fase do projeto final de um novo produto. Também, foram considerados os processos de fabricação, modelamento do produto, e análises estruturais numéricas, que são ferramentas de auxílio na otimização do produto final. Paralelamente, foram consideradas as informações dos testes experimentais para auxiliar e validar as análises estruturais numéricas, contribuindo desta forma para o aperfeiçoamento de requisitos na fase do projeto de produto, antes de sua fabricação e lançamento no mercado. Assim, este estudo apresenta como foco o desenvolvimento de um semi-reboque para transporte de cana picada, com o intuito de exemplificar e aplicar de forma prática as ferramentas estudadas e seus respectivos usos no produto em questão. Os testes de campo foram instrumentados com sensores extensométricos resistivos para coleta de dados de níveis de tensão e posterior comparação com as análises numéricas. Os dados do produto, na fase de testes experimentais, foram obtidos em condições reais de trabalho junto a uma usina do setor sucro alcooleiro. Finalmente, considerando-se os resultados de desempenho do produto, semi-reboque rodotrem para transporte de cana picada, pode-se identificar que o uso de uma metodologia de referência para o desenvolvimento de produto, apoiada por ferramentas de análise estrutural, com testes de campo instrumentados, são confiáveis e úteis aos profissionais da engenharia de projeto e manufatura. / In this paper work, a case study using a systematic methodology is presented to apply structured methods for designing new products in an industry of road implements field. Considering the road implements as industrial products, it is intended to deal with forms and processes of developing ideas and improving the generating of ideas and quest of solutions until the final phase project of a new product. The manufacturing process will also be taken into consideration, besides the modeling of the product and numerical structural analysis which are tools to help optimize the final product. In addition, will be taken in considerations the information of experimental tests to avail and validate the numerical structural analysis, and through it contribute to the improvement of requirements during the design of the product before its manufacture and market launch. This study presents the development of a semi-trailer to transport chopped sugar cane, with the purpose of exemplify and put on practice the tools which are studied and their uses applied in the product concerned. The field tests were instrumented with strain gage sensors to collect data on tension levels for later comparison to numerical analysis. This way, it is expected to have reliable data as the product will operate in a plant following through real work situations during these experimental tests. Finally, considering the results of product performance - road train semi-trailer to transport chopped sugar cane - can be identified in this study that the use of a method of reference to product development, supported by structural analysis tools, and instrumented field tests are reliable and extremely useful to the professional activities of design and manufacturing engineering.

Dentre os diversos tipos de defeitos estruturais a que um pavimento está sujeito, a deformação permanente em trilha de roda da camada de rolamento é um dos mais importantes, pois além de propiciar uma degradação acelerada da estrutura do pavimento, ele reduz consideravelmente a segurança do usuário. Este trabalho pesquisa os processos que levam à deformação permanente de revestimentos asfálticos, utilizando como estudo de caso uma pista-teste localizada na Rodovia BR 376 PR, construída com a finalidade principal de estudar os afundamentos em trilha de roda. Foram executados 10 trechos, com 200 m de extensão cada um, em aclive, na 3ª faixa de rolamento, sujeita a tráfego pesado de caminhões lentos. Os trechos experimentais consistem de restauração de pista existente, onde foram executados diferentes tipos de revestimentos asfálticos, variando-se o tipo de graduação e também o tipo de ligante asfáltico, todas dosadas pelo método Marshall. Três dos dez trechos foram submetidos ao ensaio acelerado por um simulador de tráfego móvel de pista, em escala real. As misturas asfálticas foram igualmente ensaiadas em laboratório para verificação da dosagem por equipamento giratório francês e por simulador de tráfego tipo LPC. Além disso, foram extraídas placas do revestimento asfáltico da pista-teste as quais foram submetidas ao simulador de tráfego de laboratório. O objetivo central desta pesquisa foi de estudar a consistência dos resultados obtidos em campo e em laboratório, e a previsibilidade de deformações em campo através do método laboratorial. A pesquisa verificou e analisou a redução do volume de vazios das misturas asfálticas em pista e em laboratório associadas à deformação permanente, procurando relacionar a redução do volume de vazios com a deformação. A pesquisa mostrou que os ensaios de laboratório com o simulador de tráfego LPC podem ser empregados para prever as ocorrências de afundamentos em pista. Os resultados indicam a adoção do limite máximo de 5% de deformação permanente no equipamento de laboratório para os tipos de misturas asfálticas testadas para reduzir as possíveis ocorrências de deformações permanentes de revestimentos asfálticos sujeitos a tráfego muito pesado. Nas condições dos ensaios laboratoriais da pesquisa, que se aplicam à pista-teste, as misturas asfálticas mais recomendadas quanto à resistência à deformação permanente são as misturas com asfalto modificado por polímero SBS e RET, e as misturas com asfalto-borracha. Dependendo das características do ligante, o CAP 30/45 também pode ser empregado; no entanto, o CAP 50/70 mostrou-se inadequado para tráfego pesado e lento. A graduação é uma característica relevante para a estabilidade das misturas asfálticas, devendo os agregados estarem bem entrosados no caso das graduações contínuas e bem-graduadas; no entanto a macrotextura resultante deve ser estudada para evitar superfícies fechadas que reduzam a segurança dos usuários em pistas molhadas. Foram estudadas duas misturas descontínuas gap-graded que se mostraram adequadas para tráfego pesado quanto à deformação permanente e à textura superficial. A pesquisa mostra a importância da seleção criteriosa dos materiais e rigor nos estudos de dosagem, com determinação de propriedades mecânicas para melhor prever comportamento em campo de revestimentos asfálticos sujeitos a tráfego pesado e lento. / Among the many types of structural distresses that a pavement is subjected, wheel track rutting is one of the most important because it leads to accelerated deterioration of the pavement structure and also reduces the road safety. This research focus on the processes that lead to rutting in asphalt mixes, using experimental test sites located at Highway BR 376 PR (heavy and slow traffic), which were built with the primary purpose of studying wheel path depressions. Ten testing tracks of 200 m long (total of 2 km) were built on the third lane (upward sloping). The testing tracks were part of the rehabilitation of an existing pavement. Different asphalt mixtures were designed by the Marshall method, varying the aggregate size distribution and the type of asphalt binder. Three of the ten sections were subjected to Accelerated Pavement Testing by the Heavy Vehicle Simulator (in situ). The asphalt mixtures were also prepared and tested in laboratory by the French gyratory compactor and LPC traffic simulator, respectively, in order to verify the mixtures design. In addition, plates were extracted from the asphalt surfaces in the field and then subjected to the traffic simulator in laboratory. The main purpose of this study was to compare the permanent deformation of asphalt mixtures observed in the field to that obtained in the laboratory; and also to evaluate the prediction of permanent deformation based on laboratory evaluation. This research verified the correlation between reduction in the air voids of asphalt mixtures and rutting potential (samples extracted from the field and also prepared in laboratory were analyzed). The research showed that the LPC traffic simulator is a good device to predict permanent deformation of asphalt mixtures in the field. The results indicate 5% as the threshold for the permanent deformation in laboratory to reduce the occurrence of permanent deformation of asphalt mixtures subjected to heavy traffic. For the test conditions used, the mixtures that presented better resistance to permanent deformation were the ones with asphalt modified by SBS and RET, and the asphalt-rubber mixtures. Depending on the asphalt binder characteristics, the CAP 30/45 (classification by penetration) can be used; however the CAP 50/70 presented inadequate behavior for heavy and slow traffic. The aggregate gradation is another important parameter for the stability of asphalt mixtures, where the stones need to present a good interlocking and be wellgraded. The resulting macrotexture should also be evaluated to avoid surfaces with reduced safety to the users in wet conditions. Two mixtures with gap-graded gradation were evaluated and presented good results in respect to permanent deformation and superficial characteristics (texture). This research shows the importance of materials selection, design procedure, and mechanical behavior evaluation to predict the performance of asphalt surfaces subjected to heavy and slow traffic.

In these recent years, the strengthening of masonry building has known a massive use of CFRP sheets. Those composite materials glued on the elements to reinforce are exposed to prematurely debonding crisis due to a tension load which is much smaller than the tensile strength of the CFRP. A way to upgrade failure load of CFRP-to-support bonded joint is to reinforce the cohesion between the fibers and the support by the use of mechanicals anchors built with the same fibers of the composite and fastened in the support like "nails". Research on the use of anchors for masonry supports has been limited and, in this framework, there are no experimental analyses related to the design and the placement of fiber anchors. The aim of this thesis is to provide experimental data to quantify the efficiency of the carbon fiber anchors applied on a reinforced fire brick. This is a ground work to study CFRP to masonry bonded joint fastened by fiber "nails". Specifically, the analysis of the displacement and the strain fields of the reinforced surface have been realized by means of Digital Image Correlation (DIC), an optical appealing method never used to study a FRP to support bonded joint fastened by FRP anchor. The research demonstrates that the use of the CFRP anchor increases the resistance and the ductility of the reinforcements. The latter are important to augment the mechanical features of the structural members and, especially, to increase the safety of people during earthquakes by avoiding the brittle collapse of the strengthened elements. The digital image correlation has been a good tool for the strain field analysis; strengths and weaknesses of this method have been evaluated

Le laminage est un procédé de mise en forme à chaud permettant d’obtenir des barres de différents diamètres en partant de blooms issus de la coulée continue. Dans les bruts de coulée se répartissent des inclusions qui sont de natures, de formes et de tailles différentes. Le laminage va permettre de réduire le diamètre de la barre et d’agir sur la microstructure du matériau, notamment, en fragmentant et dispersant les inclusions. L’objectif des travaux de thèse est de contribuer à la compréhension des effets du chargement thermomécanique sur l’évolution des défauts de coulée en laminage. Vu la dimension des installations, les investigations expérimentales directes sur les moyens industriels ne sont pas envisageables. L’idée développée dans les travaux de thèse concerne la mise en place et la validation d’un essai de caractérisation à échelle réduite reproduisant le chemin thermomécanique subi par la matière au cours du laminage. Pour ce faire la ligne de laminage industrielle est modélisé afin d’obtenir le chargement thermomécanique de la barre au cours du laminage. Seules les sollicitations ayant un rôle majeur sur le comportement des défauts sont reproduites. Un essai dit de « forgeage libre » a ainsi été conçu, réalisé, mis en place sur les moyens de mise en forme de la plateforme VULCAIN de l’ENSAM. L’essai a été utilisé avec des défauts artificiels présentant des similarités comme la malléabilité avec les défauts réels. Une campagne expérimentale paramétrique a été menée sur les différents types de défauts. Les échantillons forgés ont été analysés par des méthodes non destructives comme les ultrasons, la radiographie et la tomographie X. Ces analyses ont permis de suivre le comportement du défaut et d’observer certains phénomènes mis en évidence dans la littérature comme l’apparition de cavité à l’interface défaut-matrice. / Rolling is a hot forming process dedicated to manufacture bars with different diameters. The initial product is a bloom from the continuous casting. The bloom contains inclusions which have different forms, sizes and distributions. The rolling reduces the diameter of the bar and acts on the material microstructure by fragmenting and dispersing the inclusions. The aim of the thesis work is to understand the behavior of the inclusions with the rolling thermo mechanical loading effects. The direct investigations on the rolling mill are not possible because of the size of the installations. To address this problem, the solution is to develop and validate a small scale characterization test reproducing the thermo mechanical loading of the rolled bar. To achieve this, the rolling mill is modeled. Only the solicitations which have a major role on the behavior of the defects are reproduced. An open-die forging test is designed, manufactured and implemented on the VULCAIN installation of the ENSAM. The artificial defects which have a similar malleability to the real defects are integrated into the sample. A parametric experimental campaign has been conducted on the different defects. The forged samples have been analyzed with non-destructive methods such as ultrasound, radiography and tomography. These analyses allowed to follow the behavior of the defects and to observe certain phenomena illustrated in the literature such as the emergence of a cavity on the defect-matrix interface.

Dans les dernières années, le renforcement des bâtiments en maçonnerie a connu une usure massive des bandes CFRP. Ces matériaux composites, attachés sur les éléments à renforcer, sont exposés à une fracture prématurée pour délaminage (...). Une façon pour accroître la résistance maximale du système renforcé par CFRP est d'améliorer la cohésion entre support et composite en utilisant des ancrages mécaniques. Ces derniers sont réalisés en utilisant les mêmes typologies de fibres de renforcement et en les insérant dans le support comme des «clous». Les recherches scientifiques sur l'usure de cette façon d'ancrage sur support en maçonnerie ont été très limitées et, dans ce contexte, il n'y a pas d'études expérimentales sur le projet et le placement des ancrages. L'objectif principal du présent travail de thèse est de quantifier l'efficacité des ancrages en fibre de carbone appliqués sur brique (...) par les bandes CFRP. Cette recherche est la première phase d'une étude plus vaste sur les systèmes de maçonnerie-CFRP renforcés par « carbon fiber anchor ». Dans l'étude, l'analyse des déplacements et des déformations de la surface renforcée a été faite en utilisant la Corrélation des Images (DIC), une avantageuse méthode optique jamais utilisée pour l'étude des systèmes «support-CFRP band- ancrages».Le présent travail de thèse démontre que les ancrages en CFRP augmentent le résistance maximale et la ductilité des renforcements par bande de composites. Donc, cette typologie d'ancrage augmente la sécurité des personnes pendant les tremblements de terre et ne permettent pas la fracture fragile de la structure renforcée. La corrélation des images a été un bon outil pour l'étude des déformations, des avantages et des inconvénients de cette méthode et ont été évalué pendant la recherche / In these recent years, the strengthening of masonry building has known a massive use of CFRP sheets. Those composite materials glued on the elements to reinforce are exposed to prematurely debonding crisis due to a tension load which is much smaller than the tensile strength of the CFRP. A way to upgrade failure load of CFRP-to-support bonded joint is to reinforce the cohesion between the fibers and the support by the use of mechanicals anchors built with the same fibers of the composite and fastened in the support like “nails”. Research on the use of anchors for masonry supports has been limited and, in this framework, there are no experimental analyses related to the design and the placement of fiber anchors. The aim of this thesis is to provide experimental data to quantify the efficiency of the carbon fiber anchors applied on a reinforced fire brick. This is a ground work to study CFRP to masonry bonded joint fastened by fiber “nails”. Specifically, the analysis of the displacement and the strain fields of the reinforced surface have been realized by means of Digital Image Correlation (DIC), an optical appealing method never used to study a FRP to support bonded joint fastened by FRP anchor. The research demonstrates that the use of the CFRP anchor increases the resistance and the ductility of the reinforcements. The latter are important to augment the mechanical features of the structural members and, especially, to increase the safety of people during earthquakes by avoiding the brittle collapse of the strengthened elements. The digital image correlation has been a good tool for the strain field analysis; strengths and weaknesses of this method have been evaluated

[pt] O uso de nanofluidos na área de Termociências tem sido de grande interesse tendo em vista possibilitar uma melhora significativa na capacidade de transferência de calor em máquinas térmicas. Isto se deve em função da presença de partículas em suspensão com diâmetros menores que 100 nm que são dispersas em fluidos convencionais. Parâmetros como viscosidade e condutividade térmica são fatores determinantes no desempenho desses materiais como fluidos térmicos em diferentes aplicações. O presente trabalho teve como objetivo a realização de ensaios experimentais para determinação da viscosidade dinâmica e da tensão cisalhante de três nanofluidos com diferentes composições, sob condições de temperatura controlada (faixa de -10 graus Celsius a 30 graus Celsius). Dois parâmetros adicionais - taxa de cisalhamento e taxa de rotação - foram condicionantes nos ensaios. A montagem da bancada experimental foi realizada a partir do acoplamento de um viscosímetro rotativo com um banho termostático. As curvas obtidas mostraram incremento da viscosidade dinâmica com a temperatura para os nanofluidos em relação aos seus fluidos base. Houve também incremento da viscosidade relativa, sobretudo para temperaturas mais elevadas. Os nanofluidos apresentaram comportamento não newtoniano. Para elevadas taxas de cisalhamento, as medições de viscosidade tendem a valores constantes. Correlações entre viscosidade com temperatura e com taxa de cisalhamento foram construídas seguindo funções exponenciais decrescentes e de potência, respectivamente. Os resultados obtidos neste trabalho acrescentam conhecimento à literatura científica sobre a viscosidade e o comportamento reólógico de nanofluidos a baixas temperaturas. / [en] The use of nanofluids in the Thermosciences has been of great interest since it enables a substantial improvement in the heat transfer capacity in thermal machines. This is possible due to the presence particles in suspension, with diameters less than 100 nm, dispersed in conventional fluids. Parameters such as viscosity and thermal conductivity are determining factors in the performance of these materials as thermal fluids in different applications. The objective of the present work was to determine the dynamic viscosity and the shear stress of three distinct nanofluids under controlled temperature conditions (range -10 Celsius degrees to 30 Celsius degrees) at laboratory. In addition, shear rate and rotation rate were also conditioning parameters. The experimental apparatus was assembled coupling a viscometer with a thermal bath. The obtained results showed an increase of the dynamic viscosity with temperature for all nanofluids with respect to their base fluids. An increase of the relative viscosity was also observed especially at higher temperatures. The three nanofluids have shown a non-newtonian behavior. With high shear rates, the measured viscosities tended towards constant values. Curve adjustments were performed between viscosity vs temperature and viscosity vs shear rate using exponential decay function and the Power Law, respectively. The achievements of this research added scientific understanding about the viscosity and rheological behavior of nanofluids at low temperatures.

Le Principe d'Equivalence (PE) est un pilier fondamental de la Relativité Générale. Il est aujourd'hui remis en question par les tentatives d'élaborer une théorie plus exhaustive en physique fondamentale, comme la théorie des cordes. La mission spatiale MICROSCOPE vise à tester ce principe à travers l'universalité de la chute libre, avec un objectif de précision de 10-15, c'est-à-dire un gain de deux ordres de grandeurs par rapport aux expériences actuelles. Le satellite embarque deux accéléromètres électrostatiques, chacun intégrant deux masses-test. Les masses de l'accéléromètre servant au test du PE sont de compositions différentes, alors que celles de l'accéléromètre de référence sont constituées d'un même matériau. L'objectif est de mesurer la chute libre des masses-test dans le champ gravitationnel de la Terre, en mesurant leur accélération différentielle avec une précision attendue de 10-12 ms-2Hz-1/2 dans la bande d'intérêt. Une violation du PE se traduirait par une différence périodique caractéristique entre les deux accélérations. Cependant, diverses perturbations sont également mesurées en raison de la grande sensibilité de l'instrument. Certaines d'entre elles, comme les gradients de gravité et d'inertie, sont bien définies. En revanche d'autres ne sont pas modélisées ou ne le sont qu'imparfaitement, comme le bruit stochastique et les pics d'accélérations dus à l'environnement du satellite, qui peuvent entraîner des saturations de la mesure ou des données lacunaires. Ce contexte expérimental requiert le développement d'outils adaptés pour l'analyse de données, qui s'inscrivent dans le cadre général de l'analyse des séries temporelles par régression linéaire.On étudie en premier lieu la détection et l’estimation de perturbations harmoniques dans le cadre de l'analyse moindres carrés. On montre qu’avec cette technique la projection des perturbations harmoniques sur le signal de violation du PE peut être maintenue à un niveau acceptable. On analyse ensuite l'impact des pertes de données sur la performance du test du PE. On montre qu'avec l'hypothèse pire cas sur la fréquence des interruptions de données (environ 300 interruptions de 0.5 seconde par orbite, chiffre évalué avant le vol), l'incertitude des moindres carrés ordinaires est multipliée par un facteur 35 à 60. Pour compenser cet effet, une méthode de régression linéaire basée sur une estimation autorégressive du bruit est développée, qui permet de décorréler les observations disponibles, sans calcul ni inversion directs de la matrice de covariance. La variance de l'estimateur ainsi construit est proche de la valeur optimale, ce qui permet de réaliser un test du PE au niveau attendu, même en présence de pertes de données fréquentes. On met également en place une méthode pour évaluer plus précisément la DSP du bruit à partir des données disponibles, sans utilisation de modèle a priori. L'approche est fondée sur une modification de l'algorithme espérance-maximisation (EM) avec une hypothèse de régularité de la DSP, en utilisant une imputation statistique des données manquantes. On obtient une estimée de la DSP avec une erreur inférieure à 10-12 ms-2Hz-1/2. En dernier lieu, on étend les applications de l'analyse de données en étudiant la faisabilité de la mesure du gradient de gravité terrestre avec MICROSCOPE. On évalue la capacité de cette observable à déchiffrer la géométrie des grandes échelles du géopotentiel. Par simulation des signaux obtenus à partir de différents modèles du manteau terrestre profond, on montre que leurs particularités peuvent être distinguées. / The Equivalence Principle (EP) is a cornerstone of General Relativity, and is called into question by the attempts to build more comprehensive theories in fundamental physics such as string theories. The MICROSCOPE space mission aims at testing this principle through the universality of free fall, with a target precision of 10-15, two orders of magnitude better than current on-ground experiments. The satellite carries on-board two electrostatic accelerometers, each one including two test-masses. The masses of the test accelerometer are made with different materials, whereas the masses of the reference accelerometer have the same composition. The objective is to monitor the free fall of the test-masses in the gravitational field of the earth by measuring their differential accelerations with an expected precision of 10-12 ms-2Hz-1/2 in the bandwidth of interest. An EP violation would result in a characteristic periodic difference between the two accelerations. However, various perturbations are also measured because of the high sensitivity of the instrument. Some of them are well defined, e.g. gravitational and inertial gradient disturbances, but others are unmodeled, such as random noise and acceleration peaks due to the satellite environment, which can lead to saturations in the measurement or data gaps. This experimental context requires us to develop suited tools for the data analysis, which are applicable in the general framework of linear regression analysis of time series.We first study the statistical detection and estimation of unknown harmonic disturbances in a least squares framework, in the presence of a colored noise of unknown PSD. We show that with this technique the projection of the harmonic disturbances onto the WEP violation signal can be rejected. Secondly we analyze the impact of the data unavailability on the performance of the EP test. We show that with the worst case before-flight hypothesis (almost 300 gaps of 0.5 second per orbit), the uncertainty of the ordinary least squares is increased by a factor 35 to 60. To counterbalance this effect, a linear regression method based on an autoregressive estimation of the noise is developed, which allows a proper decorrelation of the available observations, without direct computation and inversion of the covariance matrix. The variance of the constructed estimator is close to the optimal value, allowing us to perform the EP test at the expected level even in case of very frequent data interruptions. In addition, we implement a method to more accurately characterize the noise PSD when data are missing, with no prior model on the noise. The approach is based on modified expectation-maximization (EM) algorithm with a smooth assumption on the PSD, and use a statistical imputation of the missing data. We obtain a PSD estimate with an error less than 10-12 ms-2Hz-1/2. Finally, we widen the applications of the data analysis by studying the feasibility of the measurement of the earth's gravitational gradient with MICROSCOPE data. We assess the ability of this set-up to decipher the large scale geometry of the geopotential. By simulating the signals obtained from different models of the earth's deep mantle, and comparing them to the expected noise level, we show that their features can be distinguished.

Le laminage est un procédé de mise en forme à chaud permettant d’obtenir des barres de différents diamètres en partant de blooms issus de la coulée continue. Dans les bruts de coulée se répartissent des inclusions qui sont de natures, de formes et de tailles différentes. Le laminage va permettre de réduire le diamètre de la barre et d’agir sur la microstructure du matériau, notamment, en fragmentant et dispersant les inclusions. L’objectif des travaux de thèse est de contribuer à la compréhension des effets du chargement thermomécanique sur l’évolution des défauts de coulée en laminage. Vu la dimension des installations, les investigations expérimentales directes sur les moyens industriels ne sont pas envisageables. L’idée développée dans les travaux de thèse concerne la mise en place et la validation d’un essai de caractérisation à échelle réduite reproduisant le chemin thermomécanique subi par la matière au cours du laminage. Pour ce faire la ligne de laminage industrielle est modélisée afin d’obtenir le chargement thermomécanique de la barre au cours du laminage. Seules les sollicitations ayant un rôle majeur sur le comportement des défauts sont reproduites. Un essai dit de « forgeage libre » a ainsi été conçu, réalisé, mis en place sur les moyens de mise en forme de la plateforme VULCAIN de l’ENSAM. L’essai a été utilisé avec des défauts artificiels présentant des similarités comme la malléabilité avec les défauts réels. Une campagne expérimentale paramétrique a été menée sur les différents types de défauts. Les échantillons forgés ont été analysés par des méthodes non destructives comme les ultrasons, la radiographie et la tomographie X. Ces analyses ont permis de suivre le comportement du défaut et d’observer certains phénomènes mis en évidence dans la littérature comme l’apparition de cavité à l’interface défaut-matrice / Rolling is a hot forming process dedicated to manufacture bars with different diameters. The initial product is a bloom from the continuous casting. The bloom contains inclusions which have different forms, sizes and distributions. The rolling reduces the diameter of the bar and acts on the material microstructure by fragmenting and dispersing the inclusions. The aim of the thesis work is to understand the behavior of the inclusions with the rolling thermo mechanical loading effects. The direct investigations on the rolling mill are not possible because of the size of the installations. To address this problem, the solution is to develop and validate a small scale characterization test reproducing the thermo mechanical loading of the rolled bar. To achieve this, the rolling mill is modeled. Only the solicitations which have a major role on the behavior of the defects are reproduced. An open-die forging test is designed, manufactured and implemented on the VULCAIN installation of the ENSAM. The artificial defects which have a similar malleability to the real defects are integrated into the sample. A parametric experimental campaign has been conducted on the different defects. The forged samples have been analyzed with non-destructive methods such as ultrasound, radiography and tomography. These analyses allowed to follow the behavior of the defects and to observe certain phenomena illustrated in the literature such as the emergence of a cavity on the defect-matrix interface.