A disposição das armaduras nos elementos estruturais não influencia somente o comportamento do elemento estrutural, mas também a facilidade e viabilidade da sua execução na obra. O detalhamento do arranjo de armadura está diretamente ligado com a segurança da construção. Os textos que existem sobre técnica de armar se encontram dispersos, dificultando o acesso dos profissionais e estudantes de engenharia de estruturas. Este trabalho analisa os vários arranjos de armaduras propostos para lajes maciças e nervuradas, vigas e pilares procurando indicar o mais adequado de acordo com os critérios de economia, facilidade de execução e comportamento do elemento estrutural, quando possível. Para melhor ilustrar os arranjos de armaduras, é apresentado o dimensionamento de um edifício residencial de pequena altura, onde, podem ser observadas as rotinas de projeto adotadas, bem como os processos para o detalhamento das armaduras. Usaram-se o programa computacional elaborado por TQS Informática Ltda e também processo não computacional. Este programa para análise estrutural de edifícios apresenta boa interface com o usuário, proporcionando-lhe grande interesse e relativa facilidade de utilização. / The disposition of the reinforcement in the structural elements does not affect only the structural element behaviour, but also the facility and the viability of the building execution. The detailing of the reinforcement arrange is directly connected to the building safety. The existing texts about the technícs of reinforcing are spread in the literature of the structural engineering, making the access of the students and professionals to them difficult. The present work analyses the many different proposed arrangements of reinforcement for the slabs, joist floors, beams and columns, trying to indicate the most adequate one, according to the economic criteria, facility of execution, and the structural element behaviour, when possible. The design of a building of a short height is presented, as a way of better visualizing the reinforcement arrangements. In that example the adopted project routines could be observed, as well as the process of detailing the reinforcements. To reach this purpose, a software designed by TQS Informática Ltda was used, as well as a non-computer process. This software for the structural analysis of building presents a good interface with the users, providing them with great interest and relative facility of use.

Un des problèmes de mise en œuvre des bétons rencontrés sur des chantiers de pieux forés à la tarière creuse est la difficulté d’introduire la cage d’armatures dans le béton frais dans 15 % des cas. Cette difficulté est liée en partie au comportement rhéologique du béton et au phénomène de ressuage qui sont des problèmes de formulation du béton. En effet, des études sur des fluides à seuil (pâtes de ciment, solutions de Carbopol, émulsions) comme le béton, montrent une corrélation entre le déplacement d’objets dans ces fluides et leurs seuils de cisaillement.L’objectif de cette étude est de développer un outil de caractérisation du béton sur chantier qui permette de tester la capacité des armatures à être introduites dans le béton à partir d’une technique basée sur le principe de la pénétrométrie. Une formulation de base de béton pour pieux a été choisie sur chantier et modifiée en laboratoire de façon à obtenir des bétons aux comportements variés (seuil de cisaillement, perte d’ouvrabilité et thixotropie) représentatifs des conditions sur site. L’influence de ces différents paramètres rhéologiques sur l’enfoncement des armatures a été étudiée. Elle a permis d’identifier des valeurs seuils pour lesquels un refus d’enfoncement de la cage d’armatures (blocage) est observé : slump<18 cm; τs>780 Pa et τ0>340 Pa.Une étude complémentaire menée sur 4 chantiers de pieux forés à la tarière creuse a permis de valider et d’affiner les conclusions précédentes et de prédire les blocages éventuels. / This study is mainly concerned with a concrete placement problem encountered on continuous flight auger (CFA) pile, namely the difficulty of introducing a reinforcement cage into fresh concrete, difficulty that occurs in 15 percent of cases. These difficulties are correlated in part with the rheological behavior of the concrete as well as with the bleeding phenomenon, both of which pertain to concrete mix design problems. Indeed, studies carried out on yield stress fluids, like concrete, reveal a correlation between object displacements in these fluids and their actual yield stresses.The aim of this study is to develop a tool for the in situ characterization of concrete at rest, based on the principles of penetrometry, which can assess the capability of introducing reinforcements into concrete.A widespread pile concrete mix design was chosen on-site and modified in the laboratory to obtain concrete mixtures with various behavior (yield stress, loss of workability and thixotropy) which are representative of on-site conditions. The influence of these rheological properties on the reinforcement embedment capacity has been studied. For low viscosity values (6 to 12 Pa.s), the rejection of reinforcement becomes a real risk for some threshold values : slump<18 cm; τs>780 Pa and τ0>340 Pa. To avoid blocking τ0 should be limited during casting process.An additional study was conducted on CFA piles on-site and helps to validate previous findings. It also describes reinforcement embedment kinetic. A correlation was found between reinforcement depreciation period during its setting and concrete viscosity.

Dans le domaine du Génie Civil, de nombreuses méthodes d’auscultation sont développées. Elles visent à aider à l’évaluation de l’état des ouvrages d’art en donnant des informations sur la structure interne ou sur l’état des matériaux. Les techniques basées sur la thermographie infrarouge sont prometteuses, elles présentent l’intérêt d’être à grand rendement et de se traduire par l’observation d’images (thermogrammes) qui semblent plus accessibles. La thèse consiste au développement d’une méthode de thermographie infrarouge active en basant sur un système d’excitation micro-ondes conçu et réalisé pour cette étude.La source micro-ondes a été réalisée sur la base d’un magnétron commercial de 800 W à 2.45 GHz associé à une antenne cornet pyramidal pour guider les ondes vers des éléments à chauffer. Par rapport aux sources utilisées classiquement en thermographie infrarouge active, les ondes électromagnétiques de type micro-ondes se propagent dans le volume d’un élément en béton. Les ondes subissent des réflexions et des effets de diffraction lorsque impactent des parties métalliques. Des phénomènes d’interférence peuvent apparaître en surface et par effet radiothermique générer des gradients de température observables par thermographie infrarouge. Ces effets se produisent de façon instantanée. En prenant en compte de toutes les consignes de sécurité, des essais avec ce nouveau système d’excitation ont été effectués dans une enceinte de protection haute fréquence. Cette nouvelle méthode a été appliquée à la détection de défauts (absence de colle) dans le cas d’un renforcement composite (CFRP), d’une pièce métallique derrière une plaque de bois d’un centimètre d’épaisseur, et plus particulièrement des armatures verticales / In the field of Civil Engineering, many inspection methods have been developed. They are intended to evaluate the condition of structures by providing information about the internal structure or status of the materials. Techniques based on infrared thermography are promising as they have the advantage of giving high performances and results by the thermograms observation that seems more accessible. The objective of the thesis is to develop a new active infrared thermography method based on a microwave excitation system designed and built for this study.The microwave source was set up based on a commercial magnetron 800 W at2.45 GHz associated to a pyramidal horn antenna for guiding microwave radiation to the heated elements. Compared to other sources traditionally used in active infrared thermography, the microwaves can propagate into the volume of a concrete element. The waves undergo the reflection and the diffraction effects while they impact any metal parts. The interference phenomena can appear on the surface and generate, by the radiothermal effect, the temperature gradients observed by infrared thermography. These effects occur instantaneously. Considering all the safety, the tests with the new excitation system were carried out in a high frequency protection cell. This new method has been applied to the defect detection (adhesive absence) in the case of a composite reinforcement (CFRP), a metal element behind a wooden plate of one centimeter of thickness, and more particularly the vertical reinforcement bars in a reinforced concrete wall.

This study is an examination of the effects of the first two waves of the Influenza Pandemic of 1918-1919 on the Canadian Expeditionary Force in Europe during the final months of the First World War. Using a case-study approach, the study analyzes the experiences of the 15th Canadian Reserve Battalion (Saskatchewan) in England and the 46th Canadian Infantry Battalion (South Saskatchewan) in France from April to 11 November 1918. While the comparison of these two battalions’ experiences is useful to see the how the Canadian Army Medical Corps reacted and responded to the outbreak of pandemic influenza in both locations, it also highlights the impact that the pandemic had on the reinforcement stream in 1918, and demonstrates the greater cost of conscription during the final months of the war. This thesis argues that that the Influenza Pandemic of 1918-1919 affected the Canadian Expeditionary Force’s Hundred Days Campaign in a way that, until now, has not been recognized. Additionally, it argues that the 15th Reserve Battalion was not to blame for bringing pandemic influenza to Bramshott Camp in the fall of 1918, and that the Canadian Army Medical Corps reacted to the outbreak as effectively as possible. Finally, it highlights the experiences of men from Saskatchewan and recounts the stories of soldiers who died of pandemic influenza.

Le renfort des matériaux composites via la croissance de nanotubes de carbone (NTC) directement à la surface des renforts textiles permet d'augmenter certaines propriétés des composites. La méthode flamme est la technique facilement industrialisable à la continue qui permet de réaliser la croissance des NTC sur des textiles. Cependant un procédé à la continue va engendrer des contraintes sur les renforts, ainsi le but de ces travaux de doctorat est de déterminer le comportement des textiles après la croissance de NTC, sous différentes contraintes de type industrielles, et d'évaluer leur influence sur la mise en œuvre et les propriétés des matériaux composites. Ces travaux ont mis en évidence la formation d'un film de transfert dès le début du frottement de surfaces textiles recouvertes de NTC contre une pièce métallique ou un autre textile de même nature. De plus, la présence des NTC a permis de mettre en évidence un comportement spécifique en indentation. La mouillabilité des surfaces avec une résine époxy n'est en revanche pas influencée par la présence des NTC, si ce n'est que très faiblement dans la dynamique du mouillage. Il a été montré que les conditions de croissance des NTC, notamment la nature du catalyseur, avaient une influence sur la résistance à long terme du film de transfert formé après frottement, sur l'adhésion des NTC sur les fibres de renfort, ainsi que sur la dynamique du mouillage avec de la résine époxy. Finalement, des matériaux composites ont été fabriqués avec des renforts avant et après usure de la surface présentant des NTC, dans le but d'étudier son influence sur les propriétés des composites. L'usure, se traduisant par la transformation des NTC en film de transfert, n'influence ni les propriétés électriques des matériaux, ni les propriétés mécaniques en flexion 3 points. / Reinforcement of composite materials with carbon nanotubes (CNTs) grafted on textiles provides an increase in the properties of the composites. The flame method is the most rapid and the easiest industrialized technique to realize the growth of CNTs on textile surfaces. At an industrial scale, some strains will be applied between the CNTs’ growth step and the composite processing, which can cause damage on the CNTs and alter the positive contribution of the CNTs to the properties of composites. That is why the aim of this study is to determine the effect of different industrial stresses on the CNTs behaviour and their influence on the composite processing and composite properties. In this work, we highlighted the formation of a transfer film, composed of CNTs, during the friction of the CNTs against metallic pieces or against the same fabric. The presence of the CNTs shows a particular behaviour in indentation. However, the wettability with an epoxy resin is not influenced by the CNTs, except a little in the dynamic of the wettability. It has been shown that the growth condition of the CNTs, particularly the catalyst, has an influence on the long term resistivity of the transfer film formed by the friction, on the adhesion of the CNTs on the fibres and on the dynamic of the wettability with an epoxy resin. Finally, composite materials composed of CNTs growth fabrics before and after the wear of the surface, were manufactured in order to study the influence of the wear on the properties of the composite material. It appears that, the wear, causing the formation of the transfer film, has no influence on the electrical and flexural properties of the composite material.

Este trabalho tem como objetivo principal apresentar formulações do método dos elementos de contorno que contemplem as análises de placas considerando-se as não-linearidades física e geométrica e de placas enrijecidas considerando-se o comportamento não-linear físico do material. As equações integrais utilizadas são baseadas na teoria de Kirchhoff para flexão de placas delgadas, sendo o efeito não-linear geométrico modelado a partir da teoria de Von Kármán. Os efeitos não-lineares físicos são introduzidos no sistema a partir da consideração de um campo de tensões iniciais, com a avaliação das regiões plastificadas realizada a partir do critério elastoplástico de von Mises com encruamento isótropo linear e particularizado para o estado plano de tensão. A formulação dos enrijecedores é efetuada de forma alternativa, com o painel enrijecido considerado como um todo e submetido a campos de momentos e forças normais iniciais para induzir o ganho de rigidez. Apenas a parcela de enrijecimento na direção longitudinal do enrijecedor é considerada. O sistema de equações algébricas é obtido a partir da discretização estrutural com elementos de contorno isoparamétricos lineares. Para a consideração dos efeitos de domínio da placa são utilizadas células triangulares com funções de aproximação linear. Já as integrais no domínio dos enrijecedores são transformadas em integrais no contorno dos mesmos, com as variáveis escritas apenas no seu eixo longitudinal. Toda a solução do sistema não-linear de equações é obtida a partir de uma formulação implícita, sendo os operadores tangentes consistentes explicitados ao longo do trabalho. Por fim, vários exemplos são apresentados de forma a validar o correto desenvolvimento das formulações propostas. / In this work a boundary element method formulation to analyse plates with combined geometrical and material nonlinearities was presented. Additionally an alternative boundary element method formulation was presented to analyse material nonlinear reinforced plates. The boundary integral equations are derived based on Kirchhoff\'s theory. An initial stress field and von Kármán hypothesis are considered to take into account the material and geometrical nonlinearities, respectively. The elastoplastic von Mises criterion with linear isotropic hardening and particularized to the plane stress condition is considered to evaluate the plastic zone. The effects of the reinforcements are taken into account by using a simplified scheme based on applying an initial stress field to correct locally the bending and stretching stiffness of the reinforcement regions. Only bending and stretching rigidities in the direction of the reinforcements are considered. Isoparametric linear elements are used to approximate the boundary unknown values and triangular internal cells with linear shape functions are used to evaluate the plate domain value influences. The domain integrals due to the presence of the reinforcements are transformed to the reinforcement/plate interface. The nonlinear system of equations is solved by using an implicit scheme together with the consistent tangent operator presented along this paper. Finally, several examples are presented to confirm the correct development of the proposed formulations.

Cette thèse s’inscrit à mi-chemin entre l’étude de la déformabilité des structures tissées et la valorisation de la fibre de lin pour des applications dans le renforcement des matériaux composites. Le premier objectif de l’étude est de caractériser expérimentalement le comportement en flexion des mèches de différentes structures constituées de fibres de lin ainsi que des tissus de différentes armures. Les travaux ont abordé aussi des paramètres tels que l’humidité relative et la composition (des mèches comélées ou en lin pure). Le deuxième objectif des travaux est d’étudier le comportement en flexion des tissus en fonction du comportement en flexion des mèches. Cette partie a commencé par la modélisation géométrique des renforts tissés dans le but de suivre l’évolution de la section du tissu qui varie dans la direction de la flexion. La modélisation mésoscopique a permis de calculer analytiquement les propriétés géométriques du tissu en particulier son moment quadratique. Les résultats obtenus ont été utilisés dans la simulation de la flexion du tissu. L’étude a permis de voir jusqu’à quel point le comportement de la mèche et le moment quadratique du tissu pilotent le comportement en flexion du tissu. D’après ces travaux, le comportement en flexion du tissu semble être approché de façon satisfaisante sur toute la gamme de longueurs envisagées à partir de ces deux grandeurs sauf pour les forts taux d’humidité où d’autres phénomènes doivent être considérés. L’étude a souligné que la différence entre deux renforts testés expérimentalement peut être anticipée numériquement. Ainsi, le concepteur de tissus sera capable d’anticiper la rigidité expérimentale du tissu pour faire des tissages adaptés à la mise en forme du renfort. Une étude paramétrique de la flexion a été également réalisée dans le but de déduire les paramètres les plus influents sur lesquels il peut jouer. / This thesis is halfway between the study of the deformability of woven structures and the use of flax fibre as reinforcement of composite materials. The first aim of the study is the experimental characterization of the bending behaviour of tows with different structures made of flax fibres and fabrics with different weaves. Parameters such as relative humidity and the composition (100% flax and commingled tows) were also considered. The second aim of the study is to link the bending behaviour of the fabric to the bending behaviour of its constituent tows. This part starts with the geometric modelling of woven fabrics in order to follow the variation of its section in the bending direction. Mesoscopic modelling allows the analytical calculation of the geometric properties of the fabric in particular its moment of inertia. The results obtained were used in the simulation of the fabrics bending to see how far the behaviour depends on the tows bending behaviour and the moment of inertia. The bending behaviour of the fabric seems to be approached satisfactorily from these two factors. This is verified within the range of lengths considered except for high humidity (in this case, other phenomena must be considered). The study pointed out that the difference between two reinforcements tested experimentally can be predicted numerically. Thus, the fabrics designer will be able to anticipate the experimental bending stiffness of the fabric in order to adapt the weaving to the shape forming. A parametric study of the bending was also achieved in order to deduce the most influential parameters of the fabric for an appropriate weaving.

Este trabalho tem como objetivo principal apresentar formulações do método dos elementos de contorno que contemplem as análises de placas considerando-se as não-linearidades física e geométrica e de placas enrijecidas considerando-se o comportamento não-linear físico do material. As equações integrais utilizadas são baseadas na teoria de Kirchhoff para flexão de placas delgadas, sendo o efeito não-linear geométrico modelado a partir da teoria de Von Kármán. Os efeitos não-lineares físicos são introduzidos no sistema a partir da consideração de um campo de tensões iniciais, com a avaliação das regiões plastificadas realizada a partir do critério elastoplástico de von Mises com encruamento isótropo linear e particularizado para o estado plano de tensão. A formulação dos enrijecedores é efetuada de forma alternativa, com o painel enrijecido considerado como um todo e submetido a campos de momentos e forças normais iniciais para induzir o ganho de rigidez. Apenas a parcela de enrijecimento na direção longitudinal do enrijecedor é considerada. O sistema de equações algébricas é obtido a partir da discretização estrutural com elementos de contorno isoparamétricos lineares. Para a consideração dos efeitos de domínio da placa são utilizadas células triangulares com funções de aproximação linear. Já as integrais no domínio dos enrijecedores são transformadas em integrais no contorno dos mesmos, com as variáveis escritas apenas no seu eixo longitudinal. Toda a solução do sistema não-linear de equações é obtida a partir de uma formulação implícita, sendo os operadores tangentes consistentes explicitados ao longo do trabalho. Por fim, vários exemplos são apresentados de forma a validar o correto desenvolvimento das formulações propostas. / In this work a boundary element method formulation to analyse plates with combined geometrical and material nonlinearities was presented. Additionally an alternative boundary element method formulation was presented to analyse material nonlinear reinforced plates. The boundary integral equations are derived based on Kirchhoff\'s theory. An initial stress field and von Kármán hypothesis are considered to take into account the material and geometrical nonlinearities, respectively. The elastoplastic von Mises criterion with linear isotropic hardening and particularized to the plane stress condition is considered to evaluate the plastic zone. The effects of the reinforcements are taken into account by using a simplified scheme based on applying an initial stress field to correct locally the bending and stretching stiffness of the reinforcement regions. Only bending and stretching rigidities in the direction of the reinforcements are considered. Isoparametric linear elements are used to approximate the boundary unknown values and triangular internal cells with linear shape functions are used to evaluate the plate domain value influences. The domain integrals due to the presence of the reinforcements are transformed to the reinforcement/plate interface. The nonlinear system of equations is solved by using an implicit scheme together with the consistent tangent operator presented along this paper. Finally, several examples are presented to confirm the correct development of the proposed formulations.

En el presente trabajo se compara el costo beneficio de dos propuestas de reforzamiento para el bloque B del Hospital Casimiro Ulloa el cual es una antigua estructura de más de 60 años de tres niveles de albañilería confinada ubicada en una zona altamente sísmica. El refuerzo convencional es a través de la implementación de placas de concreto y el no convencional es a base de láminas diagonales y anclajes de Polímero Reforzado con Fibras de Carbono (CFRP). Se realiza el análisis estructural no lineal – Pushover bajo las provisiones del ASCE/SEI 41-13 con el fin de obtener la curva de capacidad del modelo As Built y los modelos reforzados. La norma ATC-40 brinda el método de espectro de capacidad con el cual se logra obtener una visión gráfica del nivel de desempeño ya que superpone la curva de capacidad con la demanda. El cálculo de costo para ambos reforzamientos contempla el precio de los materiales, mano de obra y equipos. Por otro lado, el reforzamiento de CFRP es calculado con los valores dados por el proveedor Sika Perú. Los resultados que se obtuvieron al realizar la evaluación sísmica de los tres modelos matemáticos (As Built, placas y CFRP) en términos de capacidad estructural y costo; muestra que el reforzamiento con CFRP es la mejor opción. / This study compares the cost benefit of two reinforcement proposals for Block B of the Casimiro Ulloa Hospital, which is an old three-story, 60-year-old structure built of confined masonry located in a highly seismic area. The conventional reinforcement is through the implementation of concrete walls and the unconventional one is based on diagonal sheets and anchors of Carbon Fiber Reinforced Polymer (CFRP). The non-linear structural analysis - Pushover is performed under the provisions of ASCE/SEI 41-13 in order to obtain the capacity curve of the As Built model and the reinforced models. The ATC-40 standard provides the capacity spectrum method with which to obtain a graphic vision of the performance level since it overlays the capacity curve with the demand. The cost calculation for both reinforcements considers the price of materials, labor and equipment.. On the other hand, the reinforcement of CFRP is calculated with the values given by the provider Sika Peru. The results that were obtained when carrying out the seismic evaluation of the three mathematical models (As built, plates and CFRP) in terms of structural capacity and cost; shows that the reinforcement with CFRP is the best option / Tesis

[pt] O presente trabalho investigou o comportamento mecânico de compósitos cimentícios do tipo SHCC (Strain Hardening Cementitious Composites) de resistência comum e alta resistência, reforçados com fibras de PVA, UHMWPE (polietileno de peso molecular ultra-elevado), aço e reforços híbridos. Para o estudo, o volume total de fibras foi mantido constante em 2,0 por cento, com objetivo de manter a trabalhabilidade dos compósitos. As fibras de PVA e polietileno foram parcialmente substituídas por fibras de aço na proporção de 0,5 por cento e 1,0 por cento e a resposta mecânica foi estudada a partir de ensaios de tração direta, flexão de quatro pontos em placas e ensaios de flexão de três pontos em prismas com entalhe. O padrão de fissuração foi analisado utilizando imagens de alta resolução. O efeito escala dos compósitos reforçados com fibras de PVA e polietileno também foi investigado através de ensaios de tração direta e de flexão de quatro pontos utilizando dois tamanhos de corpos de prova. Os resultados mostraram que as fibras de PVA têm melhor desempenho que as fibras de polietileno para matrizes de resistência comum e que para ambas as matrízes, a substituição parcial das fibras de polietileno e PVA por fibras de aço tem o benefício de aumentar a resistência, mas promove redução na capacidade de deformação dos compósitos. O estudo sobre o efeito-escala também mostrou que a resposta mecânica destes materiais muda com a geometria dos corpos de prova. Por último, os compósitos foram utilizados como materiais de reparo estrutural em vigas submetidas a dano prévio e os resultados mostraram a viabilidade da utilização do SHCC como material de reparo. / [en] The present work investigated the mechanical behavior of normal and highstrength Strain Hardening Cementitious Composites (SHCC) reinforced with PVA, UHMWPE (ultra-high molecular weight polyethylene), steel and hybrid fibers. For the study, the total volume of fibers was kept constant at 2.0 percent in order to maintain the workability of the composite system. PVA and polyethylene were partially replaced by steel fibers in 0.5 percent and 1.0 percent. The mechanical response was measured under direct tension tests, four-point bending tests on plates and three point-bending tests on notched specimens. The crack pattern was investigated using high resolution image capturing procedure. The size-effect of the composites reinforced with PVA and polyethylene fibers was also investigated under direct tension test and four-point bending tests using two sizes of specimens. The results have shown that PVA fibers have a better performance than polyethylene fibers for normal strength matrices and that for both normal and high strength matrices the partial replacement of polyethylene and PVA fibers by steel fibers has the benefit of increasing the strength, but it reduces the strain capacity of the composites. The investigation about the size-effect also have shown that mechanical response of these composites changes with the geometry of the specimens. Finally, the composites were used as structural repair in beams subjected to previous damage and the results verified the feasibility of SHCC as a repair material.