Submitted by EDUARDO DA SILVA PINTO null (falecom_edu@hotmail.com) on 2017-01-11T16:16:55Z No. of bitstreams: 1 Dissertação Final Revisada.pdf: 15135107 bytes, checksum: 771e35a4fe6f9c0ef2e875ce1487b7c4 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-01-12T16:15:50Z (GMT) No. of bitstreams: 1 pinto_es_me_bauru.pdf: 15135107 bytes, checksum: 771e35a4fe6f9c0ef2e875ce1487b7c4 (MD5) / Made available in DSpace on 2017-01-12T16:15:50Z (GMT). No. of bitstreams: 1 pinto_es_me_bauru.pdf: 15135107 bytes, checksum: 771e35a4fe6f9c0ef2e875ce1487b7c4 (MD5) Previous issue date: 2016-09-16 / No presente trabalho são propostos métodos de ensaio para caracterização física e mecânica de solo-cimento compactado. Para que esse objetivo seja alcançado, é proposto um novo modelo de molde, para produção de corpos de prova, tornando os ensaios mais práticos e confiáveis, com intuito de incentivar o uso de técnicas de construção civil que gerem menos impactos ambientais negativos. Além disso, através dos resultados obtidos, pretendeu-se produzir subsídios para futuras discussões com outros pesquisadores, com intuito de que seja feita uma revisão das normas brasileiras de solo-cimento, junto a Associação Brasileira de Normas Técnicas (ABNT). Os resultados obtidos através dos ensaios realizados com o novo molde são promissores no que diz respeito a facilitar o processo de caracterização física e mecânica do material, mantendo um nível de confiabilidade compatível com o obtido através da metodologia atual. / In this research we propose a new methodology for testing physical and mechanical characterization of rammed earth stabilized with cement. For this objective to be achieved, it proposes a new mold for the production of test specimens, making it more practical and reliable, aiming to encourage the use of construction techniques that generate less negative environmental impacts. In addition, through the results obtained, we intend to generate a basis for future discussions with other researchers, with an objective to a revision of Brazilian soil-cement standards, with the Brazilian Association of Technical Standards - ABNT. Results obtained from the tests performed with the new mold are promising with regard to facilitate the process of physical and mechanical characterization of the material while maintaining a reliability level consistent with that obtained over the current methodology.

De nos jours la quasi-totalité des grandes métropoles du monde comptent avec des réseaux de transport étendus et ont pour la plupart satisfait leurs besoins de construction d’ouvrages souterrains. Cependant le parc des ouvrages existants est vieillissant et une part importante est en service depuis plusieurs décennies, par conséquence, l’entretien et la pérennisation des infrastructures souterraines existantes un enjeu majeur pour la gestion et le développement des villes. En vue d’améliorer leur politique de maintenance, c’est-à-dire pérenniser leur patrimoine et le maintenir dans de bonnes conditions de sécurité et d’exploitation, il est nécessaire que les gestionnaires d’ouvrages puissent mettre à jour leurs techniques de diagnostic (AFTES, 2005). Il est donc impératif de disposer d’outils leur permettant de mieux évaluer l’état réel des ouvrages. Or les méthodes dont disposent à l’heure actuelle les gestionnaires sont le plus souvent soit insuffisantes pour apporter une information quantitative de qualité, soit mal adaptées aux contraintes de ces ouvrages. Dans ce contexte, le projet ANR MéDiTOSS « Méthodologie de Diagnostic des Tunnels et Ouvrages Souterrains en Service » vise à développer une nouvelle méthodologie de diagnostic adaptée à ce type d’ouvrage en caractérisant les différents composants de l’ouvrage (structure du revêtement, terrain encaissant ainsi que leur interface ou contact). L’objectif de cette thèse est de fournir au gestionnaire des indicateurs physiques et mécaniques lui permettant d’orienter sa politique de maintenance en s’appuyant sur une expertise plus certaine. / Maintenance and sustainability of underground structures are the major tasks for infrastructures’ owners. To carry out these tasks, managers need to qualify the actual state of these facilities. There are very few operational methods to describe separately each component of an underground structure (structure lining, contact interface and surrounding soil). Most of them are mainly based on visual inspection. Nevertheless only the intrados of the tunnel is open to visual inspection. To improve their maintenance policy, that is to say sustain their heritage and keep it in good conditions of safety and operational, it is necessary that manager’s can update their diagnosis methods (AFTES, 2005). It is therefore imperative to have tools to better assess the actual condition of structures. However, the methods available at present managers are often either insufficient to provide quantitative information quality or poorly adapted to the constraints of these works. In this context, the ANR project MéDiTOSS "Methodology Diagnostic Tunnels and Underground Structures in Service" aims to develop a new diagnostic methodology adapted to this type of work characterizing the various components of the structure (structure of the lining, enclosing soil and their interface or contact). The objective of this thesis is to provide to the managers of physical and mechanical indicators that will guide its maintenance policy based on a certain expertise.

La corrosion des armatures constitue la principale cause de dégradation des ouvrages en béton armé, et occasionne des coûts élevés de maintenance/réparation. Pour prévenir ce problème sur ouvrages neufs, une solution consiste à renforcer les structures en béton par des armatures non-métalliques de type Polymère Renforcé de Fibres (PRF), généralement à base de fibres de verre, de carbone ou d'aramide. Il existe aujourd'hui plusieurs textes réglementaires consacrés aux armatures PRF, notamment aux USA, au Canada et au Japon, et de nombreux ouvrages en béton armé par barres en PRF ont d'ailleurs été construits dans ces pays. Cependant, si l'utilisation de ces nouvelles armatures semble à priori prometteuse, elle suscite encore des réserves de la part des maîtres d'ouvrages, notamment en France. Il subsiste en effet des incertitudes sur le comportement à long terme des structures renforcées par PRF, et plus particulièrement sur la durabilité en milieu alcalin des armatures à matrice vinylester ou époxy renforcée par des fibres de verre (PRFV), qui sont actuellement les plus utilisées, ou encore sur le vieillissement de l'interface PRF/béton. Dans ce contexte, la présente étude vise à développer pour la première fois en France, un ensemble de méthodologies permettant, d'une part, de caractériser les principales propriétés physiques, mécaniques et d'interface des différentes armatures en PRF disponibles sur le marché, mais également d'évaluer la durabilité d'armatures en PRFV (les plus représentatives du marché) et de l'interface PRFV/béton à travers des procédures pertinentes de vieillissements accélérés. La première partie de l'étude a donc été consacrée à la caractérisation physique et mécanique d'une sélection d'armatures du commerce, confectionnées à base de fibres de verre, de carbone ou d'aramide, et au comportement mécanique de l'interface entre ces PRF et le béton. Outre la caractérisation microstructurale des PRF par techniques de microscopie et d'analyse thermique, la mise en place de dispositifs d'essais de traction et de flexion 3 points à appuis rapprochés (Short-beam test) a permis d'accéder respectivement aux propriétés mécaniques en traction (module d'élasticité, résistance) et à la résistance au cisaillement inter-laminaire des armatures. Des essais spécifiques d'arrachement (Pull-out) ont ensuite permis d'évaluer l'influence de différents paramètres (type de fibre, diamètre et géométrie de surface des barres) sur le mécanisme de transfert d'effort à l'interface armature/béton. Une grande originalité de l'approche proposée réside dans l'instrumentation d'une partie des corps d'épreuve par des capteurs de déformation à fibre optique disposés au niveau de l'interface armature/béton ; ce dispositif de mesures réparties permet d'accéder à des informations locales comme le profil des déformations de traction de l'armature, et d'en déduire la longueur d'ancrage des différentes armatures dans le béton. En complément de l'étude expérimentale précédente, un travail de modélisation analytique et numérique a été initié en vue de simuler les essais d'arrachement et d'appréhender plus finement les mécanismes d'interface mis en jeu entre l'armature et le béton lors de ces essais. Dans cette optique, un modèle analytique d'interface a tout d'abord été proposé, puis introduit dans un modèle aux éléments finis (modèle d'endommagement de zones cohésives). Enfin, un protocole de vieillissement accéléré a été appliqué à des barres en PRFV seules ou noyées dans un milieu cimentaire. Les caractéristiques résiduelles des armatures et des interfaces ont été évaluées à différentes échéances de vieillissement (jusqu'à 240 jours). Hormis une diminution des propriétés mécaniques des barres soumises à une immersion directe en solution alcaline, cette condition pouvant être considérée comme très sévère par rapport aux conditions de service, il n'a pas été observé de dégradation des propriétés d'adhérence PRF/béton par rapport à l'état initial / Corrosion of the steel reinforcing bars (rebars) is the main process involved in the degradation of reinforced concrete (RC) structures, and has large repercussions on the maintenance/reparation expenses. To prevent such degradations on new infrastructures, the use of corrosion-free reinforcements, such as Fiber Reinforced Polymer (FRP) bars based on glass, carbon or aramid fibers, is gaining interest. Specific guidelines are already available in several countries (USA, Canada or Japan for instance), that define the design principles and good practices for this type of internal rebars; beside, many FRP RC structures have been built and are in service in these countries. Although the development of these new reinforcing bars is quite promising, infrastructures owners are still reluctant for their wide-scale use, especially in France. There are still major concerns regarding the long term behavior of FRP RC structures, and more particularly, the durability of glass fibers reinforced polymers (GFRP) when subjected to an alkaline environment, and the ageing behavior of the GFRP/concrete bonding as well. In this context, the present study aims at developing for the first time in France, a set of methodologies that allows : to characterize the main physical/mechanical properties of different types of FRP bars from the marketto assess the durability of GFRP bars (the most common type of bar) and their interface with concrete through relevant accelerated ageing procedures. The first part of this study was thus devoted to the physical/mechanical characterization of a selection of commercially available FRP rebars, based on glass, carbon or aramid fibers, and to the mechanical behavior of corresponding FRP/concrete interfaces. Beside the microstructural characterization of the various FRP materials by microscopy and thermal analysis techniques, tensile and short beam tests were developed in order to determine the tensile properties (Young's modulus and strength) and the interlaminar shear strength (ILSS) of the bars. Specific pull-out tests then made it possible to evaluate the influence of several parameters (type of fibers, diameter and surface geometry of the bars) on the mechanism of load transfer at the bar/concrete interface. A main originality of the proposed approach relied on the instrumentation of several test bodies by optical fiber strain sensors, which were installed along the bar/concrete interface. Such a distributed measurement system provided local information in the form of tensile strain profiles of the bars along the interface, and made it possible to determine the effective transfer length of the various types of FRP bars. As a complement to the previous experimental study, an analytical and numerical modeling work was initiated to simulate the pull-out tests and investigate more closely the interfacial mechanisms involved in the FRP bar/concrete bond behavior. In this line, an improved interface model was first proposed, which was then implemented in a finite element model (cohesive zone model formulated in the context of damage mechanics).Finally, an accelerated ageing protocol was developed and applied to the GFRP bars, either alone or embedded in a concrete medium. The retention properties of both bars and interfaces were determined after various periods of exposure (up to 240 days). Except a drop of tensile properties observed for GFRP bars that were directly immersed in an alkaline solution, which is considered as a very severe environment compared to actual service conditions, no significant loss of interfacial properties was detected on aged specimens compared to the initial state

Orientador: Jorge Luís Akasaki / Resumo: O gesso é o material sintético construtivo mais antigo que se tem notícia, e sua ampla utilização é devido as suas boas propriedades termoacústicas e de resistência ao fogo. No Brasil, seu emprego concentra-se em forros, revestimentos e paredes divisórias, conhecidas como gesso acartonado. Todavia, o gesso é um material sobre o qual existe pouco conhecimento ao nível da investigação. E este projeto se propõe a estudar mais esse material, através da confecção de compósitos a base de gesso com a incorporação de borracha de pneus, tornando-o assim um material sustentável. A borracha proveniente do processo de recauchutagem de pneus inservíveis tem ampla aplicação em pesquisas com concretos e argamassas; porém pouco se sabe sobre sua aplicação no gesso. Para atingir o objetivo proposto nesse trabalho serão feitos ensaios de microscopia eletrônica de varredura, resistência à ruptura na flexão, resistência à compressão, dureza superficial, absorção de água, densidade superficial de massa, consistência (mini-slump) e comportamento térmico. Dessa maneira, é possível afirmar que a incorporação de borracha pode ser interessante para a produção de placas de gesso, uma vez que pode incorporar um resíduo sem destino totalmente adequado, produzindo placas com características semelhantes das já utilizadas e ainda contribuindo em aspectos como densidade, dureza superficial e isolamento térmico. Sendo assim, dentre as granulometrias utilizadas neste estudo, a borracha grossa pode ser consider... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

Submitted by Nayra Alberici Pinto null (nayra_alberici@hotmail.com) on 2017-07-19T18:45:02Z No. of bitstreams: 1 dissertação nayra completa.pdf: 5169626 bytes, checksum: 36827a2bda72e89406c13683ad5a0b5d (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-07-19T19:11:12Z (GMT) No. of bitstreams: 1 pinto_na_me_ilha.pdf: 5169626 bytes, checksum: 36827a2bda72e89406c13683ad5a0b5d (MD5) / Made available in DSpace on 2017-07-19T19:11:12Z (GMT). No. of bitstreams: 1 pinto_na_me_ilha.pdf: 5169626 bytes, checksum: 36827a2bda72e89406c13683ad5a0b5d (MD5) Previous issue date: 2017-05-30 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O gesso é o material sintético construtivo mais antigo que se tem notícia, e sua ampla utilização é devido as suas boas propriedades termoacústicas e de resistência ao fogo. No Brasil, seu emprego concentra-se em forros, revestimentos e paredes divisórias, conhecidas como gesso acartonado. Todavia, o gesso é um material sobre o qual existe pouco conhecimento ao nível da investigação. E este projeto se propõe a estudar mais esse material, através da confecção de compósitos a base de gesso com a incorporação de borracha de pneus, tornando-o assim um material sustentável. A borracha proveniente do processo de recauchutagem de pneus inservíveis tem ampla aplicação em pesquisas com concretos e argamassas; porém pouco se sabe sobre sua aplicação no gesso. Para atingir o objetivo proposto nesse trabalho serão feitos ensaios de microscopia eletrônica de varredura, resistência à ruptura na flexão, resistência à compressão, dureza superficial, absorção de água, densidade superficial de massa, consistência (mini-slump) e comportamento térmico. Dessa maneira, é possível afirmar que a incorporação de borracha pode ser interessante para a produção de placas de gesso, uma vez que pode incorporar um resíduo sem destino totalmente adequado, produzindo placas com características semelhantes das já utilizadas e ainda contribuindo em aspectos como densidade, dureza superficial e isolamento térmico. Sendo assim, dentre as granulometrias utilizadas neste estudo, a borracha grossa pode ser considerada a que teve melhor desempenho, uma vez que apresentou características de ser mais trabalhável, menos absorvente e mais isolante termicamente, além de apresentar resistências à compressão e a flexão adequadas para sua utilização (não estrutural), menores mossas e maior leveza do material. / Gypsum is the oldest constructive synthetic material ever heard, and their widespread use is due to its good thermoacoustic properties and fire resistance. In Brazil, its use is focused on linings, coating and partitions, known as drywall. However, the gypsum is a material on which there is little knowledge in terms of research. And this project aims to study more this material through the production of composite gypsum with tire rubber incorporation, thus making it a sustainable material. The rubber from the retreading process scrap tires has wide application in research on concrete and mortar; but little is known about its application in gypsum. In order to reach the objective proposed in this work, scanning electron microscopy, flexural strength, compressive strength, surface hardness, water absorption, bulk density, consistency (mini-slump) and thermal behavior will be performed. In this way, it is possible to affirm that the incorporation of rubber can be interesting for the production of gypsum boards, since it can incorporate a residue without destination completely, producing plates with characteristics similar to those already used and still contributing in aspects such as density, surface hardness and thermal insulation. Thus, among the granulometries used in this study, the thick rubber can be considered the one that had better performance, since it presented characteristics of being more workable, less absorbent and more thermally insulating, besides presenting resistance to compression and flexion adequate for its use (non-structural), smaller dents and greater lightness of the material. / FAPESP: 2015/17658-4

La corrosion des armatures constitue la principale cause de dégradation des ouvrages en béton armé, et occasionne des coûts élevés de maintenance/réparation. Pour prévenir ce problème sur ouvrages neufs, une solution consiste à renforcer les structures en béton par des armatures non-métalliques de type Polymère Renforcé de Fibres (PRF), généralement à base de fibres de verre, de carbone ou d'aramide. Il existe aujourd'hui plusieurs textes réglementaires consacrés aux armatures PRF, notamment aux USA, au Canada et au Japon, et de nombreux ouvrages en béton armé par barres en PRF ont d'ailleurs été construits dans ces pays. Cependant, si l'utilisation de ces nouvelles armatures semble à priori prometteuse, elle suscite encore des réserves de la part des maîtres d'ouvrages, notamment en France. Il subsiste en effet des incertitudes sur le comportement à long terme des structures renforcées par PRF, et plus particulièrement sur la durabilité en milieu alcalin des armatures à matrice vinylester ou époxy renforcée par des fibres de verre (PRFV), qui sont actuellement les plus utilisées, ou encore sur le vieillissement de l'interface PRF/béton. Dans ce contexte, la présente étude vise à développer pour la première fois en France, un ensemble de méthodologies permettant, d'une part, de caractériser les principales propriétés physiques, mécaniques et d'interface des différentes armatures en PRF disponibles sur le marché, mais également d'évaluer la durabilité d'armatures en PRFV (les plus représentatives du marché) et de l'interface PRFV/béton à travers des procédures pertinentes de vieillissements accélérés. La première partie de l'étude a donc été consacrée à la caractérisation physique et mécanique d'une sélection d'armatures du commerce, confectionnées à base de fibres de verre, de carbone ou d'aramide, et au comportement mécanique de l'interface entre ces PRF et le béton. Outre la caractérisation microstructurale des PRF par techniques de microscopie et d'analyse thermique, la mise en place de dispositifs d'essais de traction et de flexion 3 points à appuis rapprochés (Short-beam test) a permis d'accéder respectivement aux propriétés mécaniques en traction (module d'élasticité, résistance) et à la résistance au cisaillement inter-laminaire des armatures. Des essais spécifiques d'arrachement (Pull-out) ont ensuite permis d'évaluer l'influence de différents paramètres (type de fibre, diamètre et géométrie de surface des barres) sur le mécanisme de transfert d'effort à l'interface armature/béton. Une grande originalité de l'approche proposée réside dans l'instrumentation d'une partie des corps d'épreuve par des capteurs de déformation à fibre optique disposés au niveau de l'interface armature/béton ; ce dispositif de mesures réparties permet d'accéder à des informations locales comme le profil des déformations de traction de l'armature, et d'en déduire la longueur d'ancrage des différentes armatures dans le béton. En complément de l'étude expérimentale précédente, un travail de modélisation analytique et numérique a été initié en vue de simuler les essais d'arrachement et d'appréhender plus finement les mécanismes d'interface mis en jeu entre l'armature et le béton lors de ces essais. Dans cette optique, un modèle analytique d'interface a tout d'abord été proposé, puis introduit dans un modèle aux éléments finis (modèle d'endommagement de zones cohésives). Enfin, un protocole de vieillissement accéléré a été appliqué à des barres en PRFV seules ou noyées dans un milieu cimentaire. Les caractéristiques résiduelles des armatures et des interfaces ont été évaluées à différentes échéances de vieillissement (jusqu'à 240 jours). Hormis une diminution des propriétés mécaniques des barres soumises à une immersion directe en solution alcaline, cette condition pouvant être considérée comme très sévère par rapport aux conditions de service, il n'a pas été observé de dégradation des propriétés d'adhérence PRF/béton par rapport à l'état initial / Corrosion of the steel reinforcing bars (rebars) is the main process involved in the degradation of reinforced concrete (RC) structures, and has large repercussions on the maintenance/reparation expenses. To prevent such degradations on new infrastructures, the use of corrosion-free reinforcements, such as Fiber Reinforced Polymer (FRP) bars based on glass, carbon or aramid fibers, is gaining interest. Specific guidelines are already available in several countries (USA, Canada or Japan for instance), that define the design principles and good practices for this type of internal rebars; beside, many FRP RC structures have been built and are in service in these countries. Although the development of these new reinforcing bars is quite promising, infrastructures owners are still reluctant for their wide-scale use, especially in France. There are still major concerns regarding the long term behavior of FRP RC structures, and more particularly, the durability of glass fibers reinforced polymers (GFRP) when subjected to an alkaline environment, and the ageing behavior of the GFRP/concrete bonding as well. In this context, the present study aims at developing for the first time in France, a set of methodologies that allows : to characterize the main physical/mechanical properties of different types of FRP bars from the marketto assess the durability of GFRP bars (the most common type of bar) and their interface with concrete through relevant accelerated ageing procedures. The first part of this study was thus devoted to the physical/mechanical characterization of a selection of commercially available FRP rebars, based on glass, carbon or aramid fibers, and to the mechanical behavior of corresponding FRP/concrete interfaces. Beside the microstructural characterization of the various FRP materials by microscopy and thermal analysis techniques, tensile and short beam tests were developed in order to determine the tensile properties (Young's modulus and strength) and the interlaminar shear strength (ILSS) of the bars. Specific pull-out tests then made it possible to evaluate the influence of several parameters (type of fibers, diameter and surface geometry of the bars) on the mechanism of load transfer at the bar/concrete interface. A main originality of the proposed approach relied on the instrumentation of several test bodies by optical fiber strain sensors, which were installed along the bar/concrete interface. Such a distributed measurement system provided local information in the form of tensile strain profiles of the bars along the interface, and made it possible to determine the effective transfer length of the various types of FRP bars. As a complement to the previous experimental study, an analytical and numerical modeling work was initiated to simulate the pull-out tests and investigate more closely the interfacial mechanisms involved in the FRP bar/concrete bond behavior. In this line, an improved interface model was first proposed, which was then implemented in a finite element model (cohesive zone model formulated in the context of damage mechanics).Finally, an accelerated ageing protocol was developed and applied to the GFRP bars, either alone or embedded in a concrete medium. The retention properties of both bars and interfaces were determined after various periods of exposure (up to 240 days). Except a drop of tensile properties observed for GFRP bars that were directly immersed in an alkaline solution, which is considered as a very severe environment compared to actual service conditions, no significant loss of interfacial properties was detected on aged specimens compared to the initial state