Orientador: Newton de Oliveira Pinto Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-08T14:07:26Z (GMT). No. of bitstreams: 1 Galletto_Adriana_M.pdf: 4576824 bytes, checksum: bb2af65a6526865497bbe467584e09d5 (MD5) Previous issue date: 2005 / Resumo: o setor de reparo e reforço de concreto vem apresentando relevante importância na indústria da construção civil pelo aumento do volume de trabalho nesta área. Um dos métodos mais usuais de reparação estrutural é a remoção do concreto deteriorado e sua recomposição por meio da ligação com outro concreto, utilizando produtos denominados pontes de aderência. Entretanto, a falta de normalização e experiência científica acumulada conduz ao emprego desses materiais baseado somente em informações dos fabricantes e em experiências pessoais dos aplicadores, o que mostra a necessidade de um maior número de pesquisas acadêmicas sobre o assunto. O programa experimental desenvolvido avaliou o desempenho de três diferentes sistemas adesivos usualmente utilizados nos reparos estruturais (junta seca, adesivo à base de epóxi e adesivo à base de resina acrilica), por meio do ensaio de compressão-cisalhamento de prismas de concreto reconstituídos com junta diagonal (slant shear test), levando em consideração características como ângulo, umidade e rugosidade da superficie da interface, comparados á prismas monolíticos de concreto e em termos de critério de Mohr-Coulomb. Os resultados mostram que alguns sistemas de reparo podem prejudicar a resistência de aderência, como é o caso dos adesivos à base de resina acrilica, enquanto o epóxi é capaz de promover a aderência até mesmo em situações onde o ângulo da junta é considerado crítico / Abstract: The repair section and concrete reinforcement comes presenting important in the industry of the construction for the increase of the work volume in this area. One of the most usual methods of structural repair is the removal of the deteriorated concrete and its repair by means of the connection with other concrete, using products of adherence. However, the normalization lack and accumulated scientific experience drives to the employment of those materials only based on the makers' information and in personal experiences of the professional, what shows the need of a larger number of academic researches on the subject. The developed experimental program usually evaluated the acting of three diferent adhesive systems used in the structural repairs (it joins drought, sticker to the epoxy and sticker to the base of acrylic resin), by means of the rehearsal of slant shear test of concrete prisms reconstituted with diagonal committee, taking in consideration characteristics as angle, humidity and roughness of the surface of the interface, compared monolithic prisms of concrete and in terms of approach of Mohr-Coulomb. The results show that some repair systems can harm the resistance of adherence, as it is the case of the stickers to the acrylic resin, while the epoxy is capable to promote the adherence even in situations where the angle ofthe committee is considered critical / Mestrado / Edificações / Mestre em Engenharia Civil

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / During the history of the Civil Engineering, it is witnessed the appearance of a new age, which emphasizes quality in general, and durability, in particular, of the concrete structures. As a result of a continuable search for quality, an evolution in a relatively new field is observed, named Structural Pathology, which relates to the study of structural imperfections in constructions. An efficient solution for this problem is the structural repair, that appears as a strong market share of the industry of the civil construction, motivating the development of a number of materials and procedures of repair that aim to reestablish the original conditions of the damaged structure in order to extend its service life. For the protection and the restoration of the concrete structures, there were developed repair materials destined to different situations of application. The Microscopy, historically applied to the biomedical sciences, field has been spreaded out to the science of the materials field as well, becoming an important tool in the study of diverse properties. The main objective of this research is to investigate the form of linking and bond between repair mortars and concrete, by using microscopy. In this research 247 micrographs were analysed from 24 samples of four types of repair mostars amongst the ones found in the market had been analyzed. The typical morphologic characteristics of those materials were studied through of the optic microscope (OM) and the scanning electron microscope (SEM). The results presented in research provides the understanding of the microscopical analisis related to the bond of someone repair materials. / Ao longo da história da Engenharia Civil, testemunha-se o surgimento de uma nova era, na qual se enfatiza a qualidade em geral e, particularmente, a durabilidade das estruturas de concreto. Como resultado de uma incessante busca pela qualidade, observa-se uma evolução em um campo relativamente novo, designado por Patologia Estrutural, que se relaciona ao estudo de falhas estruturais em obras civis. Uma solução eficaz para este problema é a recuperação estrutural, que surge como um forte segmento de mercado da indústria da construção civil, motivando o desenvolvimento de uma série de materiais e procedimentos de recuperação que visam a restabelecer as condições originais da estrutura danificada e ampliar a sua vida útil. Para a proteção e recuperação das estruturas de concreto, foram desenvolvidos materiais específicos destinados a diferentes situações de aplicação. A microscopia, historicamente aplicada no seguimento das ciências biomédicas, tem sido difundida também para a ciência dos materiais, tornando-se uma ferramenta importante no estudo de diversas propriedades. O objetivo principal deste trabalho é investigar a forma de ligação e aderência entre o concreto e o material de reparo, mediante microscopia. Nesta pesquisa, foram analisadas 247 micrografias em 24 amostras de quatro tipos de argamassas de reparo dentre os encontrados no mercado. As características morfológicas típicas destes materiais foram estudadas com o auxílio do microscópio óptico (MO) e do microscópio eletrônico de varredura (MEV). Os resultados apresentados neste trabalho auxiliam a compreensão da análise microscópica relacionada à aderência de um determinado material de reparo ultilizado. / Mestre em Engenharia Civil

Concrete is the most widely used material in construction and infrastructure, and is often reinforced by steel to improve tensile strength. Despite its enduring popularity, the material’s inherent weaknesses – namely corrosion damage and material fatigue – combined with ageing infrastructure, poses a challenge to both decision-makers and civil engineers to optimise sustainable infrastructure services. This article explores and synthesises the sustainable potential of maintenance and repair methods using concrete and cement-based composite materials. We draw on published case studies where sustainability assessments have been applied within this field. We also included cases that describe themselves as a type of sustainability assessment, but lack the assessment of all dimensions. Our research aims, firstly, to identify what maintenance interventions were assessed by means of sustainability criteria. Second, it explores the basic conceptual understanding which underlies each sustainability assessment. Third, it analyses the many methodological choices made for system boundaries, selection of indicators, or forms of aggregation. We have applied a systematic literature review to develop evidence-based management knowledge; this shows that current sustainability assessments are diverse regarding system boundaries, their scope, levels of detail, and overall quality. Although there is a trend towards more holistic types of assessment, environmental and economic sustainability dominated our sample, with global warming and energy consumed being most often reported. External costs, if included in the assessment, drive the overall economic score, while life cycle sustainability assessment is applied to only three cases. The most critical and challenging issues were shown to be the long-term orientation of maintenance measures and the complexity of undertaking a truly holistic sustainability assessment. To that end, we have stimulated scholarly discussion on further methodological progress to align with the good practices identified in our review, and call for greater application of these methods in the construction industry.