Ces travaux portent sur la réparation et le renforcement de structures béton armé par matériaux composite. Dans ce domaine, la solution de type carbone-époxy appliqué sur les faces extérieures des structures occupe une place prépondérante, mais reste perfectible. L'objectif principal de cette thèse est de proposer des solutions alternatives à ces matériaux, tels que les composites de type textile-mortier (Textile Reinforced Concrete, « TRC ») et d'en juger la faisabilité, les performances et le comportement. Une approche expérimentale et analytique, aux échelles micro, méso et macroscopiques, est menée en s'appuyant notamment sur la technique de mesure de champs de déplacements par corrélation d'images. À l'égard de l'étude du matériau, une procédure d’essai de caractérisation en traction directe des TRC a été conçue et validée. La conduite de 98 essais par cette procédure, a permis de mieux appréhender le comportement de ces composites, notamment l’articulation entre les mécanismes locaux et leur traduction à l’échelle macroscopique. Les principaux leviers permettant l'optimisation des TRC ont ainsi été déterminés. À l'échelle structurelle, l'étude de 11 poutres réparées vis-à-vis de l'effort tranchant, par collage de plats préfabriqués ou moulage à même la poutre, a été conduite. Il en ressort que les solutions TRC se comparent favorablement à celles de type carbone-époxy. Aussi, le comportement local a été finement évalué, notamment, l'évolution des efforts repris par le renfort TRC ainsi que la validité du modèle analytique du treillis. Un comportement de type multifissurant ou pull-out du TRC sensible à son procédé de mise en oeuvre a également été mis en avant / This research focuses on repairing and strengthening concrete structures with composite materials. In this particular domain, carbon-epoxy composites are of considerable interest, but still room for improvement. The main objective of this thesis is to show alternatives to these composites, such as Textile Reinforced Concrete (TRC). Feasibility, performances and behavior of this alternative composite are examined. An experimental and analytical approach, at the micro-, meso- and macroscopic scale are conducted, notably thanks to the technique of digital image correlation for in-plane displacement measurement. Regarding the study of the material, a rather handy, reliable and efficient procedure of a direct tensile test was designed and validated. To enable a better understanding of the TRC behavior, 98 different TRC configurations were tested thanks to this procedure. The links between local mechanisms and macroscopic scale behavior were notably studied. Finally, key levers for optimizing the TRC were determined. On the structural level, a study was conducted on 11 beams shear strengthened by bonding of prefabricated plates or by contact molding. It shows that TRC solutions compare favorably with carbon-epoxy composites. Also, the local behavior was thoroughly assessed, notably the change of forces carried by the composite material and the truss model validity. A multi-cracking or pull-out behavior of the TRC was put forward depending on its application process

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This research has as main objective to analyze the Math Notebook of the Covenant by National High School Strengthening (Pacto Nacional pelo Fortalecimento do Ensino Médio PNEM), to understand how mathematics was presented and see if it includes curriculum changes that might represent a trend of Mathematics Education. The Ministerial Decree No. 1140 of November 22, 2013, established the PNEM, with the stated aim of promoting the appreciation of the continuing education of teachers and coordinators who worked in High School public. The theoretical framework that supports this research was based on the reading of official documents, which supported the continuing education of teachers of the PNEM, reading articles and dissertations about PNEM, High school, Program High School Groundbreaking (Programa Ensino Médio Inovador ProEMI). The methodological framework used was the Content Analysis, as the study of Laurence Bardin. Following the analysis of the work guidelines, we chose the Math Notebook of the PNEM as the context unit. The definition of the initial categories was carried out with the help of software for qualitative data analysis MAXQDA®, conducting the search, the encoding and extracting the coded segments needed for the analysis of Math Notebook. After this step, we define the intermediate categories and final categories of analysis. Thus, it was possible to recognize the PNEM's contribution to the continuing education of teachers and coordinators of High School, allowing teachers had the opportunity to reflect on the curriculum of this stage of basic education in all units of the federation. / Esta pesquisa tem como objetivo geral analisar o Caderno de Matemática do Pacto Nacional pelo Fortalecimento do Ensino Médio (PNEM), para compreender como a Matemática foi apresentada e verificar se ele contempla mudanças curriculares que possam representar uma tendência da Educação Matemática. O PNEM foi instituído pela Portaria Ministerial nº 1.140, de 22 de novembro de 2013, com o objetivo declarado de promover a valorização da formação continuada dos professores e coordenadores pedagógicos que atuavam no Ensino Médio público. O referencial teórico que sustenta esta pesquisa é baseado na leitura dos documentos oficiais que deram suporte à formação continuada de professores do PNEM, na leitura de artigos e dissertações sobre PNEM, Ensino Médio, Programa Ensino Médio Inovador (ProEMI). O referencial metodológico utilizado nesta pesquisa foi a Análise de Conteúdo, conforme os estudos de Laurence Bardin. Seguindo as orientações de análise da obra, elegemos o Caderno de Matemática do PNEM como a unidade de contexto. A definição das categorias inicias foi realizada com o auxílio do software para análise de dados qualitativos MAXQDA®, que realiza a busca, a codificação e a extração dos segmentos codificados necessários para a análise do Caderno de Matemática. Após essa etapa, definimos as categorias intermediárias e as categorias finais de análise. Dessa forma, foi possível reconhecer a contribuição do PNEM para a formação continuada dos professores e coordenadores pedagógicos do Ensino Médio, permitindo que os docentes tivessem a oportunidade de refletir sobre o currículo dessa etapa da educação básica em todas as unidades da federação.

Le renforcement de structures ou d'éléments de structure par collage de plats PRF (polymères renforcés de fibres) est une technique actuellement reconnue et utilisée dans le monde entier. Il permet d'augmenter la durée de vie des structures existantes ce qui est très intéressant du point de vue développement durable et est souvent plus intéressant d'un point de vue économique. La première partie de ce travail s'intéresse au renforcement de poutres béton armé par des plats PRF. En effet, ce type de renforcement peut engendrer une rupture prématurée de type peeling-off. Ce mode de ruine très fragile résulte du décollement du béton d'enrobage qui reste collé au matériau de renforcement. Pour une conception optimale d'un renforcement en flexion par collage, il est important d'être en mesure de prévoir ce type de rupture et d'en tenir compte dans le dimensionnement. Pour cela, un modèle numérique fiable de type élasto-plastique est dans un premier temps présenté qui permet de prévoir la rupture de type peeling-off. Ce modèle est validé à l'aide de résultats d'essais expérimentaux. Les paramètres principaux affectant l'efficacité du renforcement sont ensuite mis en évidence dans le cadre d'une étude paramétrique. Les résultats de cette étude sont mis en parallèle avec des résultats d'essais de la littérature prouvant ainsi l'efficacité du modèle proposé. Enfin, plusieurs mesures sont proposées pour améliorer la performance du renforcement et éviter la rupture prématurée de peeling-off. La deuxième partie de ce travail s'attache quant à elle à l'étude de renforcement de tabliers de ponts soumis aux efforts éventuels d'impact d'un véhicule sur une barrière de sécurité. Une campagne expérimentale composée de différentes configurations de dalles est d'abord réalisée. Un modèle numérique s'inspirant du modèle proposé précédemment est ensuite présenté. La confrontation des résultats expérimentaux et numériques montre une concordance encourageante avant la fissuration majeure de la dalle. Enfin, les résultats mettent en relief l'efficacité du renforcement par des plats PRF dans le cas de glissières de sécurité / Strengthening of structures by bonding FRP plates (fiber reinforced polymer) is a technique currently recognized and used worldwide. This method is a viable solution to costly replacement of deteriorating structures and increases the life of reinforced structures. The first part of this doctoral work focuses on the strengthening of reinforced concrete beams with FRP plates and more precisely on a premature failure caused by this type of reinforcement called peeling-off or concrete cover separation. This brittle failure mode which prevents the strengthened RC beams from attaining their ultimate flexural capacity involves the tearing-off of the concrete cover along the level of tension steel reinforcement starting from a plate end. The first step for a successful, safe and economic design of flexural strengthening using FRP composite at the bottom of the beam is then to predict such failure and to take it into account in design. A reliable numerical model analysis which is validated by test results is first presented to predict ultimate loading capacity and the failure mode of RC beams in a four-point bending setup. The main parameters affecting the efficiency of the reinforcement are then highlighted in a parametric study. The results of this study are compared with test results in the literature demonstrating the efficiency of the proposed model. Finally, several measures are proposed to improve the performance of the strengthening and in order to avoid the premature rupture of peeling-off. The second part of this work is concerned with the strengthening study of a bridge deck subject to eventual loads generated by a car crash into a safety barrier. A series of equivalent impact tests is first performed on deck slabs. A numerical model inspired by the previously proposed model for RC beams is then presented. Comparisons between the predictions of the numerical model and test results show a good agreement before the major cracking of the slab. Finally, the results highlight the efficiency of FRP plates in the case of safety guardrails

Objectives: We sought to examine the gender differences between low back pain (LBP) and muscle strengthening activity (MSA) in U.S. adults (≥20 years of age). Background: Low back pain is a well-known medical condition that has been shown to impact quality of life and professional productivity. It also adds to the financial burden of our healthcare system by augmenting medical treatment costs. Muscle strengthening activity is a recognized method to prevent and treat LBP. Studies analyzing the relationship between MSA and LBP by gender have produced mixed results. Methods: The sample (n=12,721) included participants in the 1999-2004 National Health and Nutrition Examination Survey (NHANES). Three categories of reported MSA participation were created: no MSA (referent group), some MSA (≥1 to/wk), and meeting the 2008 Department of Health and Human Services (DHHS) recommendation (>2 d/wk). The dependent variable was LBP. Results: Gender stratified analysis revealed significantly lower odds ratio of reporting LBP for women (OR 0.82; 95% CI 0.70-0.96, P=0.03) and men (OR 0.86; 95% CI 0.70-0.96, P=0.01) reporting volumes of MSA meeting the DHHS recommendation. Following adjustment for smoking, the odds ratio remained significant in women (P=0.03) but not in men (P=0.21). Conclusions: Men and women reporting volumes of MSA meeting the current DHHS recommendation were found to have lower odds of reporting LBP when compared to those reporting no MSA prior to adjustment for smoking. After adjustment for smoking, the association between MSA and LBP continued to be significant in females but in males. These findings suggest that smoking may be an important mediating factor that should be considered in LBP research.

Background: Muscular strengthening activity (MSA) has been shown to be inversely associated with insulin resistance (IR). The associations between quartiles of the homeostatic model assessment of insulin resistance (HOMA-IR) and self-reported MSA in a nationally representative sample of euglycemic U.S. adults were examined. Methods: Sample included adult participants (≥20 years of age [n=2,543]) from the 1999-2004 National Health and Nutrition Examination Survey (NHANES). HOMA-IR was categorized into quartiles based on every 25th percentile. No MSA was the dependent variable. Results: Following adjustment for covariates, those with HOMA-IR values in third (p Conclusions: Having a higher HOMA-IR value is associated with greater odds of reporting no MSA in euglycemic U.S. adults.

La mejora de la eficiencia de las centrales térmicas mediante el aumento de la temperatura y la presión de trabajo permite reducir el consumo de combustibles fósiles y las emisiones de CO2 , pero requiere el desarrollo de nuevos materiales capaces de soportar estas condiciones más extremas. En el presente trabajo se han estudiado nuevos aceros que podrían ser utilizados para la fabricación de componentes en centrales térmicas de alta eficiencia y baja emisión de CO2 . Se han clasificado en dos grupos, Grupo I: Aceros con 14 % Cr diseñados para aplicaciones hasta 650 ºC y Grupo II: Aceros con 2,25% Cr diseñados para aplicaciones hasta 600 ºC. Las distintas aleaciones fueron obtenidas por colada y laminadas a 900 ºC. Posteriormente se sometieron a un tratamiento térmico de solubilización y revenido para la obtención de una microestructura de martensita revenida reforzada con partículas de segunda fase, finas y homogéneamente distribuidas. La caracterización mecánica se realizó entre 540 y 650 ºC mediante ensayos de compresión con cambios en la velocidad de deformación y ensayos de fluencia. Para la identificación de las fases presentes y el análisis de los cambios microestructurales que se producen durante el tiempo de permanencia a alta temperatura, las aleaciones fueron estudiadas tanto antes como después de los ensayos mecánicos, mediante difracción de rayos X, dureza Vickers, microscopía óptica y electrónica de barrido y transmisión (SEM y TEM) y difracción de electrones retrodispersados (EBSD). Se detectó un cambio de comportamiento entre las regiones de alta y baja tensión y una pérdida de resistencia asociada a la degradación microestructural sufrida durante el tiempo de permanencia a elevada temperatura. A pesar de esto, algunas aleaciones alcanzan tensiones de rotura cercanas a los 100 MPa a 100.000 horas, debido a la gran interacción existente entre las dislocaciones y las partículas de refuerzo. / Benavente Martínez, E. (2014). Estudio de la microestructura y las propiedades mecánicas de nuevos aceros diseñados para aplicaciones en centrales térmicas de alta eficiencia y baja emisión de CO2 [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/39349 / TESIS

The eco-friendly alternatives use is increasing momentum in a conscious effort towards sustainability. In this regards, the relevance and the economic value of using copper slag as a concrete aggregate are explored in this study in order to contribute towards metallurgical waste recycling. Emphasis is placed on the evaluation of the concretes strengthening prepared with copper slag contents and produced under four curing methods: water immersion, water spraying, plastic sheet covering and air-drying. In each curing case excluding for water immersion, was duplicated in indoors (i.e. in the laboratory) and outdoor exposure (so was prone to varying environmental conditions). This was specifically aimed at capturing the effects of tropical weather conditions typical of the Lualaba province in the Democratic Republic of Congo. The control mix was designed to reach 25 MPa of compressive strength. Copper slag was successively incorporated as sand replacement at the following mass fractions: 20 %, 40 % and 60 %. Freshly mixed concrete samples were evaluated for workability. Cube specimens were cast accordingly, cured for 28 days and then tested for density and compressive strength. Results indicated an increase in strength up to 20 % of replacement rate for all the curing methods. Further additions resulted in reduction in the strength, but the rate of reduction depended on curing conditions. The increase in strength was mainly credited to the physical properties of copper slag that could have contributed to the cohesion of the concrete matrix. It has been found that appropriate ways of curing can still achieve greater results than that of the control mix since 80 % of humidity is ensure. The two-way ANOVA test performed on the 28-days compressive strength values confirmed the significant influence of the curing methods, of copper slag content and the interaction between them. It has been found that considerable influence is attributed to copper slag content and that warm environmental conditions further extend the concrete strengthening. / College of Engineering, Science and Technology / M. Tech. (Chemical Engineering)

The diploma thesis aims to describe the process of family strengthening of two services provided by Regional Caritas Jičín. It also compares the services using a good practice approach, which is defined by multidisciplinary cooperation and a network of activities of various organizations. The theoretical part of the thesis describes the process of family strengthening and explains terms such as family and its functions, multi-problem family, the vulnerability of contemporary family, family typology, or various socio-pathological phenomena. In this part, the objectives, principles, and legal framework of family strengthening are described. Two researched social activation services providing family strengthening are introduced. The setting of the system of care in Czechia is outlined, including its current issues and the ongoing transformation. Moreover, the innovative concepts of cooperation and methods of social work are introduced, i.e. multidisciplinary teams, child protection conferences, family conferences, or the Cochem model. The practical part of the thesis sets out three research objectives and describes the approach to the research, including its ethics, the researchers' position, and the method used for data collection - the semi-structured interview. Furthermore, the research analysis is...

The diploma thesis is focused on the design of structural support and construction modifications of a baroque wine cellar, which is part of a double-storeyed house. The first part deals with the statical analysis and structural support of a masonry barrel vault, which was loaded with a new building. The second part deals with the reconstruction of the double-storeyed object, which is in a state of disrepair with heavily developed cracks. The thesis contains a technical report, analysis of statics, drawing documentation and the work progress. The calculation of internal forces were executed by the software Scia Engineer 2017. The drawing documentation contains a formwork and reinforcement drawing, maping of cracks, leading of tensions in the walls and vault including of floor plans, sections and elevations, production plans of base plates and deviators, reinforcement drawing of concrete bond beam and finally the construction process of upper construction.

Dissertation focuses on strengthening of axially loaded steel members strengthened under load. Strengthening under load using welding is time and financially efficient. Plastic design can be used for members without stability problems. However, the design of members susceptible to buckling is difficult and opinions of researchers differ on this matter and there are only several experiments. The dissertation is focused on strengthening under load of members with selected cross-sections susceptible to flexural buckling. It is necessary to check the resistance of the base member weakened by the elevated temperatures caused by welding. The preload and welding – residual stress and deformations – must be taken into account for the determination of the buckling resistance of the member strengthened under load. The aim of this dissertation is to provide the load resistance of selected compressed members strengthened under load. Author performed experiments on members with the H and L shaped cross-sections and seamless tubes. Other experiments were performed on members with H shaped cross-section and rectangular hollow sections to determine the resistance of base member during welding. These served to validate numerical models which helped to increase the number of specimens for statistical evaluation. Analytical models to determine the load resistances of the base member during welding and the strengthened member were developed using experiments from literature and author’s experiments and numerical models. The simplified model is conservative and suitable for practical design. The complex model is suitable for scientific purpose and it provides both deformation and load resistance using modified imperfection factor. It provides a good agreement with the experiments. Doctoral thesis also includes practical recommendations for design and execution of strengthening under load using welding.