The objective of this research was to explore and demonstrate the production andperformance of fiber-reinforced polymer (FRP) rebar manufactured on a continuous threedimensionalbraiding machine for use as reinforcement in concrete structures. Differentconfigurations of fiberglass/epoxy composite cylindrical rebar rods were manufactured,embedded in concrete, and tested in axial tension to identify the relationships betweenmanufacturing parameters and tensile pull-out strength of the rebar. The strength of the bondbetween concrete and FRP rebar was investigated using the pull-out test detailed by ACI 440.3R-12. The rebar was a No. 4 size and produced by combining multiple tows of fiberglass/epoxyprepreg to form the core of cylindrical rods which were consolidated using spirally-woundaramid consolidation fibers. The manufactured rebar was cured at 121°C (250°F) as specified bythe material manufacturer, TCR Composites. Preliminary research performed on carbon/epoxyrebar guided the process of developing a test matrix based on multiple variables. Primaryvariables investigated included the nature of the consolidation fiber material (dry vs prepreg),and the use of sand coating as a secondary process. The rebar samples were cast in 200 mm x200 mm x 200 mm (8.0 in x 8.0 in x 8.0 in) concrete cubes to investigate bond strength. A testfixture was designed and fabricated for use on a universal tensile testing machine. Standard 12.7mm (0.5 in) diameter steel rebar and a commercially comparable fiberglass rebar were alsotested to provide baseline values. Measurements were collected at both the free and loaded endsof the rebar with free-end results being a more accurate presentation of rebar bond stress.Results showed that the bond strength was 6-13% higher for the free-end for rebarconsolidated with a dry tow compared to prepreg tow consolidated rebar. When sand was added,dry tow consolidated sand-coated samples showed higher bond stress in the range of 15-26% forthe free-end than samples consolidated with a dry tow but excluded sand coating. Samplesconsolidated with prepreg tow and coated with sand showed higher bond stress in the range of43-58% for the free-end compared to prepreg tow no-sand coating samples. Overall, for therebar manufactured on the 3-D braiding machine, the prepreg tow consolidated rebar samplesrecorded the highest bond strength values with a maximum average bond stress value of 15.2MPa (2.26 ksi). The dry tow sand consolidated rebar recorded a maximum average bond stressvalue of 11.4 MPa (1.65 ksi). The rebar purchased from American Fiberglass Rebar recorded amaximum average bond stress of 12.0 MPa (1.74 ksi) while the maximum average bond stress ofsteel rebar was 13.1 MPa (1.90 ksi). Results demonstrated that quality composite rebar can bemanufactured using the 3-D braiding machine and that consolidating the rebar with a prepregtow and coating the surface with sand resulted in a rebar which bonded well with concretecompared to commercialized FRP and steel rebar.

The objective of this research was to explore and demonstrate the production andperformance of fiber-reinforced polymer (FRP) rebar manufactured on a continuous threedimensionalbraiding machine for use as reinforcement in concrete structures. Differentconfigurations of fiberglass/epoxy composite cylindrical rebar rods were manufactured,embedded in concrete, and tested in axial tension to identify the relationships betweenmanufacturing parameters and tensile pull-out strength of the rebar. The strength of the bondbetween concrete and FRP rebar was investigated using the pull-out test detailed by ACI 440.3R-12. The rebar was a No. 4 size and produced by combining multiple tows of fiberglass/epoxyprepreg to form the core of cylindrical rods which were consolidated using spirally-woundaramid consolidation fibers. The manufactured rebar was cured at 121C (250F) as specified bythe material manufacturer, TCR Composites. Preliminary research performed on carbon/epoxyrebar guided the process of developing a test matrix based on multiple variables. Primaryvariables investigated included the nature of the consolidation fiber material (dry vs prepreg),and the use of sand coating as a secondary process. The rebar samples were cast in 200 mm x200 mm x 200 mm (8.0 in x 8.0 in x 8.0 in) concrete cubes to investigate bond strength. A testfixture was designed and fabricated for use on a universal tensile testing machine. Standard 12.7mm (0.5 in) diameter steel rebar and a commercially comparable fiberglass rebar were alsotested to provide baseline values. Measurements were collected at both the free and loaded endsof the rebar with free-end results being a more accurate presentation of rebar bond stress.Results showed that the bond strength was 6-13% higher for the free-end for rebarconsolidated with a dry tow compared to prepreg tow consolidated rebar. When sand was added,dry tow consolidated sand-coated samples showed higher bond stress in the range of 15-26% forthe free-end than samples consolidated with a dry tow but excluded sand coating. Samplesconsolidated with prepreg tow and coated with sand showed higher bond stress in the range of43-58% for the free-end compared to prepreg tow no-sand coating samples. Overall, for therebar manufactured on the 3-D braiding machine, the prepreg tow consolidated rebar samplesrecorded the highest bond strength values with a maximum average bond stress value of 15.2MPa (2.26 ksi). The dry tow sand consolidated rebar recorded a maximum average bond stressvalue of 11.4 MPa (1.65 ksi). The rebar purchased from American Fiberglass Rebar recorded amaximum average bond stress of 12.0 MPa (1.74 ksi) while the maximum average bond stress ofsteel rebar was 13.1 MPa (1.90 ksi). Results demonstrated that quality composite rebar can bemanufactured using the 3-D braiding machine and that consolidating the rebar with a prepregtow and coating the surface with sand resulted in a rebar which bonded well with concretecompared to commercialized FRP and steel rebar.

No description available.

Objective: The objective of this study was to evaluate the bond strength of fiberglass posts (Exacto N° 2 ®) cemented with resin cement (RC) and resin modified glass ionomer cement (RMGI), with and without ultrasonic activation in the root canal of bovine teeth. The penetration of the cements into dentine tubules was also assessed. Methods: Forty bovine incisors were selected and endodontically treated, and then divided into 4 groups (n = 10). Fiberglass posts were cemented with RC and RMGI and activated with an ultrasound insert in 2 groups; the other two groups received no ultrasonic activation. After 1 week of cementation, the roots were sectioned into 9 slices of approximately 1,5 mm each. Confocal microscopy and push-out test were performed, and all specimens were subjected to 200x magnification optical microscopy for mode of failure evaluation. Statistical analysis was done with three-way ANOVA, followed by the Fishers test ( = 0.05). Results: There was no difference among the root thirds in the RMGI group while a difference was found among the thirds in the RC group. In addition, the bond strength of the RC group was higher than the RMGI group, in all thirds. The RC also showed a greater penetration than the RMGI, in all thirds, with and without activation. The ultrasound activation caused a greater penetration only in the cervical and middle thirds in the RMGI group, and in the middle third of the RC group. Conclusion: The RC presented higher bond strength and penetration compared to the RMGI and ultrasonic activation improved the penetration of the RMGI cement in the middle and cervical root thirds and of the RC in the middle root third. A significant correlation between bond strength and penetration was verified in all groups. Clinical relevance: Ultrasound can promote a better penetration of resin cements used in fiberglass post cementation, reaching the most difficult anatomical areas in the root canal. / Objetivo: O objetivo deste estudo foi avaliar a resistência de união de pinos de fibra de vidro (Exacto N°2 ) com e sem ativação ultrassônica, associado a dois materiais: cimento resinoso (CR) e cimento ionomerico modificado com resina (CIMR), nos terços radiculares através de teste push-out e de Microscopia Confocal para avaliar a penetração dos cimentos. Métodos: Quarenta incisivos bovinos foram selecionados e tratados endodonticamente, depois divididos em 4 grupos (n=10): em dois grupos os pinos de fibra de vidro foram cimentados com CR e CIMR, e ativados com um inserto de ultrassom; nos outros dois grupos não foi realizada ativação ultrassônica. Após 1 semana da cimentação, as raízes foram seccionadas em 9 fatias de aproximadamente 1,5 mm cada. A microscopia confocal e o teste push-out foi realizado, e todos os espécimes foram submetidos a microscopia óptica com 200 vezes de aumento para avaliação do módulo de falha. Os valores de resistência de união (RU) foram submetidos a ANOVA a três critérios, seguido de Fisher ( = 0.05). Resultados. Os resultados deste estudo em relação a resistência de união, mostrou que não houve diferença entre os terços no CIMR e houve diferença entre os terços no cimento CR, além disso os valores de resistência de união dos espécimes do cimento CR foram acima dos espécimes do cimento CIMR e essa diferença se repete para todos os terços. Com relação a penetração na comparação dos materiais, o CR mostrou sempre apresentar uma penetração maior do que o cimento CIMR, em todos os terços com e sem ativação. Com relação a ativação verificou-se que a ativação com o ultrassom apresentou maior penetração somente no terço cervical e médio no cimento CIMR, e no CR no terço médio. Conclusão: O CR apresentou melhor resistência de união e penetração, em comparação com o cimento CIMR e que a ativação com ultrassom melhorou a penetração do terço médio e cervical no cimento CIMR e Terço médio no cimento CR além de isso tem uma correlação importante que a maior área de penetração maior resistência de união. Relevância Clínica: o uso do ultrassom pode promover uma melhor penetração dos cimentos resinosos para a cimentação de pinos fibras de vidro intracanal, alcançando as áreas anatômicas mais difíceis dentro do canal radicular.

A presente pesquisa teve como objetivo avaliar o uso de compósitos de fibras e resina epóxi no reforço de emendas dentadas em peças de madeira. Inicialmente, foi avaliada a influência da trama das fibras de sisal e de curauá sem tratamento nenhum nas propriedades mecânicas à tração dos compósitos com resina epóxi. Igualmente, foram caracterizados na tração compósitos de fibras de vidro e tecidos de sisal. Posteriormente, foi avaliada a resistência à tração paralela às fibras de peças de madeira Pinus sp em tamanho estrutural para três tipos de tratamentos: (1) peças sem emendas e sem reforço, (2) peças com emendas e sem reforço e (3) peças com emendas reforçadas por compósitos de fibras de vidro e resina epóxi. Também foram realizados testes de tração em corpos de prova isentos de defeitos com emendas dentadas usando madeira Lyptus® para três casos: (1) sem reforço na emenda, (2) reforço na emenda com fibra de vidro e (3) reforço na emenda com tecido de sisal. Os resultados da influência da trama das fibras de sisal e curauá com a resina epóxi nos testes de tração mostraram que o tipo de trama não influenciou significativamente na resistência e no módulo de elasticidade. Na caracterização dos compósitos poliméricos, a resistência do tecido de sisal foi cerca de 44% da resistência da fibra de vidro. Nas peças estruturais, devido à baixa resistência da madeira de Pinus sp utilizada, não se justificou a utilização do reforço. Nos corpos de prova isentos de defeitos de madeira Lyptus® com emendas dentadas, a eficácia do reforço foi evidenciado, com aumento de 37% na resistência à tração com reforço de fibra de vidro e de 40% com reforço de tecido de sisal, em relação aos corpos de prova isentos de defeitos sem reforço. / The present research evaluate the reinforcing of finger joints in timber pieces with composite fiber and epoxy. Initially, the influence of the weft in the tensile mechanical properties of composites using sisal fibers and curaua without any treatment was evaluated. The characterization of composites made with sisal fibers and glass fibers were also carried out. Additionally, the tensile strength parallel to the grain for pieces of Pinus sp in structural sizes for three types of treatments: (1) pieces without finger joints, (2) pieces unreinforced finger joints and (3) pieces reinforced finger joints with composite fiberglass and epoxy resin, was evaluated. Also, was evaluated the tensile strength of the finger joint test specimens Lyptus® wood for three cases: (1) unreinforced finger joint, (2) reinforced finger jointed with fiberglass and (3) reinforced finger jointed with fabric sisal. The results of influence of the weft sisal fibers and curaua with epoxy resin of tensile test showed that the weft did not significantly influence the strength and the modulus of elasticity. The characterization of polymeric composites, the strength of sisal fabric was about 44% of the fiber glass strength. The structural size pieces, the use of reinforcement it is not justified due to the low strength of the Pinus sp wood used. The test specimens of Lyptus® wood with finger joints, the efficacy of the reinforcement was evident, with 37% increase in tensile strength with glass fiber reinforcement and 40% with reinforcement sisal fabric, compared to specimens without reinforcement.

A presente pesquisa teve como objetivo avaliar o uso de compósitos de fibras e resina epóxi no reforço de emendas dentadas em peças de madeira. Inicialmente, foi avaliada a influência da trama das fibras de sisal e de curauá sem tratamento nenhum nas propriedades mecânicas à tração dos compósitos com resina epóxi. Igualmente, foram caracterizados na tração compósitos de fibras de vidro e tecidos de sisal. Posteriormente, foi avaliada a resistência à tração paralela às fibras de peças de madeira Pinus sp em tamanho estrutural para três tipos de tratamentos: (1) peças sem emendas e sem reforço, (2) peças com emendas e sem reforço e (3) peças com emendas reforçadas por compósitos de fibras de vidro e resina epóxi. Também foram realizados testes de tração em corpos de prova isentos de defeitos com emendas dentadas usando madeira Lyptus® para três casos: (1) sem reforço na emenda, (2) reforço na emenda com fibra de vidro e (3) reforço na emenda com tecido de sisal. Os resultados da influência da trama das fibras de sisal e curauá com a resina epóxi nos testes de tração mostraram que o tipo de trama não influenciou significativamente na resistência e no módulo de elasticidade. Na caracterização dos compósitos poliméricos, a resistência do tecido de sisal foi cerca de 44% da resistência da fibra de vidro. Nas peças estruturais, devido à baixa resistência da madeira de Pinus sp utilizada, não se justificou a utilização do reforço. Nos corpos de prova isentos de defeitos de madeira Lyptus® com emendas dentadas, a eficácia do reforço foi evidenciado, com aumento de 37% na resistência à tração com reforço de fibra de vidro e de 40% com reforço de tecido de sisal, em relação aos corpos de prova isentos de defeitos sem reforço. / The present research evaluate the reinforcing of finger joints in timber pieces with composite fiber and epoxy. Initially, the influence of the weft in the tensile mechanical properties of composites using sisal fibers and curaua without any treatment was evaluated. The characterization of composites made with sisal fibers and glass fibers were also carried out. Additionally, the tensile strength parallel to the grain for pieces of Pinus sp in structural sizes for three types of treatments: (1) pieces without finger joints, (2) pieces unreinforced finger joints and (3) pieces reinforced finger joints with composite fiberglass and epoxy resin, was evaluated. Also, was evaluated the tensile strength of the finger joint test specimens Lyptus® wood for three cases: (1) unreinforced finger joint, (2) reinforced finger jointed with fiberglass and (3) reinforced finger jointed with fabric sisal. The results of influence of the weft sisal fibers and curaua with epoxy resin of tensile test showed that the weft did not significantly influence the strength and the modulus of elasticity. The characterization of polymeric composites, the strength of sisal fabric was about 44% of the fiber glass strength. The structural size pieces, the use of reinforcement it is not justified due to the low strength of the Pinus sp wood used. The test specimens of Lyptus® wood with finger joints, the efficacy of the reinforcement was evident, with 37% increase in tensile strength with glass fiber reinforcement and 40% with reinforcement sisal fabric, compared to specimens without reinforcement.

Submitted by RAFAELA ANDRADE DE VASCONCELOS null (rafaela-vasconcelos@hotmail.com) on 2016-04-27T21:04:50Z No. of bitstreams: 1 vasconcelos_ra_dr_sjc.pdf: 1223725 bytes, checksum: f212f1adab3c030b4b7089bfeacaf463 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-04-27T21:10:57Z (GMT) No. of bitstreams: 1 vasconcelos_ra_dr_sjc.pdf: 1223725 bytes, checksum: f212f1adab3c030b4b7089bfeacaf463 (MD5) / Made available in DSpace on 2016-04-27T21:10:57Z (GMT). No. of bitstreams: 1 vasconcelos_ra_dr_sjc.pdf: 1223725 bytes, checksum: f212f1adab3c030b4b7089bfeacaf463 (MD5) Previous issue date: 2016-03-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O propósito deste estudo foi avaliar, in vitro, a influência de remanescente de materiais obturadores endodônticos, após desobturação e preparo para pino, sobre a resistência de união adesiva de pinos de fibra de vidro cimentados. Foram utilizados 60 dentes humanos unirradiculados sem coroa. As raízes foram preparadas pela técnica coroa-ápice com sistema Reciproc. Para obturação, as raízes foram divididas em grupos (n = 10) de acordo com o cimento endodôntico utilizado: SO= sem obturação; GP=guta percha sem cimento; AHP= guta-percha + AHPlus; SLP= guta-percha + Sealapex; IRT= guta-percha + iRoot SP; e ERZ= guta-percha + EndoRez. As raízes foram obturadas pela técnica do cone único. A cimentação dos pinos de fibra de vidro Rebilda n.12 foi realizada com sistema adesivo futurabond DC e cimento Rebilda DC em 10 mm do comprimento da raiz. Após esse período, as raízes foram seccionadas obtendo-se discos de 2 mm de espessura em cada terço da raiz (3 discos por raiz) que foram submetidos ao teste de push out, análise por meio de uma lupa estereoscópica (40x) para identificação através de scores da presença de remanescente de material obturador na luz do canal e avaliação por espectroscopia de energia dispersiva (EDS) para identificação de remanescente de componentes químicos do cimento endodôntico presentes nos túbulos dentinários. Os dados obtidos foram analisados estatisticamente pelos testes de Kruskal Wallis, Qui Quadrado e teste de Anova e Tukey, todos com nível de significância de 5%. Não houve diferença estatística para a resistência adesiva entre os cimentos na região cervical (p = 0,49), media (p = 0,28) e apical (p = 0,09). Os grupos SLP e ERZ apresentaram menos remanescente de material obturador nas regiões cervical (p = 0,045) e apical (p = 0,006). Significantes diferenças de remanescentes de componentes químicos foram observadas na região apical dos grupos AHP, IRT e SLP. Conclui-se que os materiais endodônticos não influenciaram na resistência de união adesiva de pinos de fibra de vidro. / The purpose of this study was to evaluate the influence of remnants endodontic filling material in root canal on the bond strength of fiberglass posts cemented. Sixty single-rooted human teeth were used.Crowns were removed. The roots were prepared by crown-down technique with Reciproc system. For fillings, the roots were divided (n = 10) according to the sealer used: SO- without fillings; GP-gutta-percha without sealer; AHP- gutta-percha + AHPlus; SLP- gutta-percha + Sealapex; IRT-gutta-percha + iRoot SP; ERZ-and gutta-percha + EndoRez. Single cone obturation technique was used. After root canal fillings, the teeth were kept in an oven 37 0C for 7 days. Cementing fiberglass posts Rebilda n.12 was performed with fiber adhesive system Futurabond DC and cement Rebilda DC in 10 mm of root length, getting stored in an oven at 37 0C for 48 h. After this period, roots were sectioned obtaining 1 disc of 2 mm thickness in each third of the root (3 discs per root), this discs were underwent to push out test, analyzed by means of a stereomicroscope (40x) to identify the presence of remnants of filling material in the lumen of the canal, and then evaluated by energy dispersive spectroscopy (EDS) for identification of chemical components remnants sealer present in the dentinal tubules. Datas were analyzed with Kruskal-Wallis test, Chi square test, and also Anova and Tukey test, 5% of significance. There were no significant differences in push-out bond strengths among the different groups in the coronal (p = 0.49), middle (p = 0.28) or apical third (p = 0.09). Sealeapex and EndoRez groups showed significantly less remnants of filling material at coronal (p = 0.045) and apical levels (p = 0.006).Significant differences of chemical components remnants were found in AHP, IRT and SLP groups on apical third. It is concluded that residual endodontic filling material does not influence on the bond strength of fiberglass.

Made available in DSpace on 2016-06-02T19:19:57Z (GMT). No. of bitstreams: 1 GARCIA_Andre_2013.pdf: 15819879 bytes, checksum: 9190fa1c1e1cd61a69da76af1922b664 (MD5) Previous issue date: 2013-03-18 / The use of shields in real estates (buildings and houses) in Brazil and in the World, the manufacture of armored doors, shields and walls is increasing and becoming a very promising market worldwide. Nowadays, in this shield area, the use of steel as raw material in the construction of panels for levels of protection called IIA is predominant. An alternative for this material is the development of composite materials of polymer matrix reinforced with fibers. In this context, the work involves the development of panels in composite of epoxy matrixes reinforced with fiberglass and elastomeric nanoparticles. The objective of this research was comparing the performance of composite panels with and without use of the particles. The method used for molding the composite panels was the lamination of sheets with six and ten HPG (High Performance Glass) layers of fiberglass by hot pressing process, using epoxy resin (DGEBA) with nanoparticles of rubber (butadiene) in addition as a matrix. To evaluate the performance of the molded composites, mechanical tests were realized, including Tensile Strength, Flexure Strength, Interlaminar Shear Strength, Izod Impact Strength, and Ballistic Impact tests (with 40 hand gun). Beyond that, other tests were also performed: physical-chemical, rate fiber/resin, void content and mass per unit area (weight). Besides that, some DMTA (Dynamic Mechanical Thermal Analyzer) were also performed in samples of resin (matrix) and laminates. Within the laminates molded and analyzed, it can be highlighted that the laminates containing elastomeric particles in the epoxy matrix, promoted the decreasing of density about 14% and increasing of the ballistic impact strength of the laminate. / No Brasil e no mundo a utilização de blindagens em imóveis (prédios e casas), e na fabricação de portas, escudos e paredes blindadas vem aumentando e se tornando um mercado bastante promissor. Nesta área de blindagem, atualmente, predomina a utilização de aço como matéria-prima para construção de painéis para níveis de proteção balística denominados IIA. Uma alternativa para esse material é o desenvolvimento de materiais compósitos de matrizes poliméricas reforçados com fibras. Dentro deste contexto, este trabalho envolve o desenvolvimento de painéis em compósito de matriz epóxi (DGEBA) com nanopartículas de borracha reforçada com fibras de vidro HPG (High Perfomance Glass). A pesquisa teve como objetivo comparar o desempenho dos painéis compósitos com e sem a utilização das nanopartículas. O método utilizado para moldagem dos painéis compósitos foi a laminação de chapas com seis e dez camadas de fibras de vidro tipo HPG (High Performance Glass), por processo de prensagem à quente, utilizando como matriz a resina epóxi (DGEBA) aditivada com nanopartículas de borracha (butadieno). Para avaliar o desempenho dos compósitos moldados foram realizados ensaios mecânicos de resistência à tração, resistência à flexão, cisalhamento interlaminar; resistência ao Impacto Izod, ensaios de impacto balístico com pistola calibre .40 de polegada, além de ensaios físico-químicos, fração fibra/resina, concentração de vazios, densidade e gramatura. Também foram realizadas algumas análises de DMTA (análise térmica dinâmico-mecânica) em amostras da resina (matriz) e dos laminados. Dentre os laminados moldados e analisados pode-se destacar que o laminado contendo nanopartículas elastoméricas na matriz epóxi proporcionou a diminuição da densidade em torno de 14% e aumento da resistência ao impacto balístico do laminado.

Made available in DSpace on 2014-12-17T14:58:08Z (GMT). No. of bitstreams: 1 NelsonRD_DISSERT.pdf: 6410040 bytes, checksum: b984ed383486a723e2f3e4c87e50d6c7 (MD5) Previous issue date: 2011-06-20 / This research work is based, in search of reinforcement s vegetable alternative to polymer composites. The idealization of making a hybrid composite reinforced with vegetable fibers licuri with synthetic fibers is a pioneer in this area. Thus was conceived a hybrid composite laminate consisting of 05 (five) layers being 03 (three) webs of synthetic fibers of glass and E-02 (two) unidirectional fabrics of vegetable fibers licuri. In the configuration of the laminate layers have alternating distribution. The composite laminate was manufactured in Tecniplas Commerce & Industry LTD, in the form of a card through the manufacturing process of hand lay up. Licuri fibers used in making the foil were the City of Mare Island in the state of Bahia. After cooking and the idealization of the hybrid composite laminate, the objective of this research work has focused on evaluating the performance of the mechanical properties (ultimate strength, stiffness and elongation at break) through uniaxial tensile tests and three point bending. Comparative studies of the mechanical properties and as well as among other types of laminated hybrid composites studied previously, were performed. Promising results were found with respect to the mechanical properties of strength and stiffness to the hybridization process idealized here. To complement the entire study were analyzed in terms of macroscopic and microscopic characteristics of the fracture for all tests. / O presente trabalho de investiga??o baseia-se na busca de refor?os vegetais alternativos aos comp?sitos polim?ricos. A idealiza??o de confeccionar um comp?sito h?brido com refor?o de fibras vegetais de licuri com as fibras sint?ticas ? pioneira nessa ?rea. Para tanto foi idealizado um laminado comp?sito hibrido constitu?do de 05 (cinco) camadas sendo 03 (tr?s) de mantas de fibras sint?ticas de vidro-E e 02 (duas) de tecidos unidirecionais de fibras vegetais de licuri. Na configura??o do laminado as camadas possuem distribui??o alternada. O laminado comp?sito foi fabricado, industrialmente, na forma de uma placa, atrav?s do processo de fabrica??o de lamina??o manual (hand lay up). As fibras de licuri utilizadas para a confec??o do laminado foram da cidade de Ilha de Mar? no estado da Bahia. Ap?s a idealiza??o e confec??o do laminado comp?sito h?brido, o objetivo desse trabalho de investiga??o se concentrou em avaliar o desempenho das propriedades mec?nicas (resist?ncia ?ltima, rigidez e deforma??o na ruptura), atrav?s dos ensaios de tra??o uniaxial e flex?o de tr?s pontos. Estudos comparativos entre as propriedades mec?nicas obtidas, bem como entre outros tipos de laminados comp?sitos h?bridos j? estudados, foram realizados. Resultados promissores foram encontrados com rela??o ?s propriedades mec?nicas de resist?ncia e rigidez para esse processo de hibridiza??o aqui idealizado. Para complementa??o de todo o estudo foram realizadas an?lises macrosc?picas e microsc?picas das caracter?sticas da fratura para todos os ensaios.

Made available in DSpace on 2014-12-17T14:58:25Z (GMT). No. of bitstreams: 1 GustavoAB.pdf: 2461248 bytes, checksum: 0536be02b6961005820ca67a7e2765de (MD5) Previous issue date: 2007-01-19 / Fillers are often added in composites to enhance performance and/or to reduce cost. Fiberglass pipes must meet performance requirements and industrial sand is frequently added for the pipe to be cost competitive. The sand is added to increase pipe wall thickness, thus increase pipe stiffness. The main goal of the present work is to conduct an experimental investigation between pipes fabricated with and without de addition of sand, to be used in the petroleum industry. Pipes were built using E-glass fibers, polyester resin and siliceous sand. The fabrication process used hand lay up and filament winding and was divided in two different parts: the liner and the structural wall. All tested pipes had the same liner, but different structural wall composition, which is the layer where siliceous sand may be added or not. The comparative investigation was developed considering the results of longitudinal tensile tests, hoop tensile tests, hydrostatic pressure leak tests and parallel-plate loading stiffness tests. SEM was used to analyze if the sand caused any damage to the glass fibers, during the fabrication process, because of the fiber-sand contact. The procedure was also used to verify the composite conditions after the hydrostatic pressure leak test. The results proved that the addition of siliceous sand reduced the leak pressure in about 17 %. In the other hand, this loss in pressure was compensated by a stiffness increment of more than 380 %. MEV analyses show that it is possible to find damage on the fiber-sand contact, but on a very small amount. On most cases, the contact occurs without damage evidences. In summary, the addition of sand filler represented a 27.8 % of cost reduction, when compared to a pipe designed with glass fiber and resin only. This cost reduction combined to the good mechanical tests results make siliceous sand filler suitable for fiberglass pressure pipes / Cargas de adi??o s?o utilizadas com freq??ncia, em materiais comp?sitos, para atingir propriedades mec?nicas requeridas por normas e para redu??o de custos. As tubula??es em pl?stico refor?ado com fibras de vidro (PRFV), utilizadas para aplica??es com altas press?es, devem atender a requisitos m?nimos de projeto estabelecidos em normas. Para tanto, a areia vem sendo utilizada como carga de adi??o, no sentido de manter os tubos em PRFV competitivos no mercado. A areia ? adicionada para aumentar a espessura da parede, aumentando com isso a rigidez. Este trabalho teve como principal objetivo analisar a influ?ncia da areia nas propriedades mec?nicas de tubula??es de PRFV, visando sua aplica??o na ind?stria do petr?leo e do g?s, atrav?s de ensaios comparativos entre tubos com e sem a adi??o de areia. Os tubos foram fabricados com fibras de vidro tipo E na forma de fios cont?nuos e manta, resina poli?ster ortoft?lica e areia quartzosa. A fabrica??o foi realizada em duas etapas distintas, sendo a primeira camada do tubo denominada de barreira qu?mica (processo de lamina??o manual) e a segunda camada denominada estrutura (fabricada pelo processo de filamento cont?nuo). A areia ? adicionada no tubo juntamente com as camadas de filamento cont?nuo e, portanto, ? um constituinte da estrutura do tubo. A an?lise comparativa foi conduzida atrav?s de ensaios de tra??o axial e ircunferencial, press?o hidrost?tica e rigidez, al?m de an?lises com microsc?pio eletr?nico de varredura (MEV). Foram avaliadas as for?as resultantes de ruptura e o m?dulo de elasticidade circunferencial, al?m da rigidez. As an?lises com MEV foram conduzidas para verificar a presen?a de danos causados as fibras, durante o processo de fabrica??o, e para verificar as condi??es do laminado ap?s os ensaios de press?o hidrost?tica. Os resultados mostraram que a adi??o de areia causou uma redu??o na press?o de ruptura do tubo de 17 %. Por?m esta perda foi compensada pelo grande acr?scimo na rigidez que foi da ordem de 380 % . As an?lises no MEV mostraram que ocorrem danos durante o processo de fabrica??o, mas em quantidades muito pequenas. Na maioria dos casos o contato areia/fibras ocorre sem evid?ncias de danos. Em resumo, a areia representa uma redu??o de 27,8 % no custo final do tubo, que somado aos bons resultados obtidos nos ensaios mec?nicos, faz deste material uma excelente op??o de carga de adi??o para tubula??es de PRFV utilizadas com altas press?es