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Ao meu orientador, Prof. Dr. Túlio Nogueira Bittencourt, pelas oportunidades oferecidas, orientação e conselhos que ajudaram a trilhar o meu caminho durante a elaboração desta dissertação. À minha esposa, Cristina, pelo companheirismo, amizade, apoio e paciência em todos os momentos juntos. À minha família e à minha avó Jane Giacomin (in memoriam), por estarem por perto, torcendo por mim. Aos meus sogros, Waldir e Eugélica, pelo carinho, incentivo e inspiração. Ao meu avô, Waldemar Mendes de Andrade (in memoriam), pelas sábias e eternas palavras e grande incentivo a busca do conhecimento. Ao meu colega Phil L Stone, por me mostrar as belezas da Engenharia. Minha sincera admiração. Ao Sr. Alfredo P. C. Neto, pelo compartilhamento de sua vasta experiência com estruturas. Ao Prof. Dr. Leandro Mouta Trautwein, pela amizade e apoio durante a elaboração dos modelos numéricos e desta dissertação; A todos os colegas do GMEC, que me ajudaram direta ou indiretamente nestes dois anos. Em especial, gostaria de destacar o apoio de Luís Bitencourt e Alberto Colombo, pela paciência e compartilhamento de suas máquinas para o processamento dos meus modelos, e Leila Valverdes e Ritermayer Teixeira, pela grande contribuição a esta dissertação. À Concessionária OHL, por todo o apoio logístico para tornar possível o monitoramento da ponte.

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This paper investigates the bond behavior between a bio-aggregate and a cement-based matrix. The experimental evaluation comprised physical, chemical, image, and mechanical characterization of the bio-aggregate. The image analyses about the bio-aggregate’s outer structure provided first insights to understand the particularities of this newly proposed bio-aggregate for use in cementitious materials. A mineral aggregate (granitic rock), largely used as coarse aggregate in the Brazilian civil construction industry, was used as reference. The bond behavior of both aggregates was evaluated via pull-out tests. The results indicated that both aggregates presented a similar linear elastic branch up to each respective peak loads. The peak load magnitude of the mineral aggregate indicated a better chemical adhesion when compared to the bio-aggregate’s. The post-peak behavior, however, indicated a smoother softening branch for the bio-aggregate, corroborated by the microscopy image analyses. Although further investigation is required, the macaúba crushed endocarp was found to be a thriving bio-material to be used as bio-aggregate.

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This research aimed to improve the impregnation of XSBR (Carboxylate Styrene Butadiene Rubber) polymer on jute yarns, and hence the mechanical properties of a TRCC (Textile-Reinforced Cementitious Composite). Thus, an experimental investigation on the use of microcrystalline and nanofibrillated cellulose as additives to XSBR admixture was carried out. Four different solutions containing XSBR are presented, and each solution-fiber interaction and each treated fiber-matrix interaction were analysed. For those interaction analyses, the influence of XSBR impregnation was evaluated via SEM (Scanning Electron Microscopy) and TGA (Thermogravimetric Analysis), while the mechanical properties of the non-treated and treated jute fibers were evaluated via direct tensile test, and the bond between the treated and non-treated jute yarn and the cementitious matrix was evaluated via pull-out tests. Results showed a prominent enhancement not only to the mechanical behavior of the treated fibers, but to the TRCC's as well. Mathematics Subject Classification (2020) MSC code1 · MSC code2 · more

The growing global energy demand requires solutions that improve energy efficiency in all sectors. The civil construction sector is responsible for a large part of global energy consumption. In this context, phase change materials (PCMs) can be incorporated into construction materials to improve the energy efficiency of buildings. The purpose of this study was to incorporate a PCM to jute fabric, applying it in civil construction as a reinforcement for cement matrices. In order to do that, a method of immersing jute fabric in liquid phase change material, and then coating it with a polymer, was proposed. Treated jute fabric was then used to produce a laminated composite with a cementitious matrix. Morphological, mechanical and chemical characterization of jute textiles was performed, as well as an analysis of the composites’ mechanical and thermal behavior. The results verified that jute textiles absorbed 102% PCM in weight, which was successfully contained in the capillary porosity of jute. The PCM was able to delay the composite’s temperature increase by up to 24 °C. It was concluded that this method can be used to incorporate PCM to natural textiles, producing composites with thermal energy storage properties.