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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
951

Kurdish Guests or Syrian Refugees? : Negotiating Displacement, Identity and Belonging in the Kurdistan Region

Bahram, Haqqi January 2018 (has links)
With the conflict ongoing in Syria since 2011, many Syrian Kurds have been forced to leave their homes to seek safety and security in the Kurdistan Region of Iraq (KRI). Their displacement to KRI is a distinctive experience of migration as it has happened within an intra-ethnic setting of Syrian Kurds, as refugees, encountering Iraqi Kurds, as hosts. Sharing ethnic identification and imagination of a historical homeland but holding different nationalities, has turned identity and belonging into sites of contestation between the refugees and the hosts. Within this intra-ethnic setting of displacement, the study has investigated the construction of home and politics of identity and belonging among the refugees in relation to protection regimes and forms of inclusion and exclusion. This has been done through a content analysis of relevant policy and regulations for refugees in KRI and Iraq and a thematic analysis of individual narrative interviews with the refugees themselves. Research results from the policy analysis have indicated the lack of a comprehensive protection regime in Iraq and KRI, and the deployment of the ‘guests’ rhetoric towards the refugees as a responsibility evasion mechanism. Results from the interviews have revealed that home for the participants is plural, and it connects to Syria and Kurdistan to varying degrees. Their identity as Kurds is contested when their Syrianness is evoked with boundaries limiting their recognition to be both Syrian and Kurdish. Similarly, their belonging is challenged with their social position as refugees and their legal belonging to Syria. With this, they get involved into a continuum of politics of identity and belonging ranging between the situational demonstration of their Syrian identity and the role of ‘the successful Syrian refugee’, and the accentuation of their attachment to Kurdishness through belonging to Rojava. These politics have been discussed as reflecting a process of reconstructing Syrian Kurdish identity in the light of the experience of displacement and the intra-ethnic encounter. Contextualizing the research results in a wider perspective, it is argued that they carry further implications related to the Kurdish struggle with identity and belonging, not only in KRI, but in all the other parts of Kurdistan.
952

La migration et le déplacement comme manifestations de la violence dans la littérature et le cinéma méditerranéens et sub-sahariens francophones (1990-2010) / Migration and Displacement as Manifestations of Violence in Mediterranean and Sub-Saharan Francophone Literature and Cinema (1990-2010)

Apap, Anabel 14 April 2018 (has links)
La migration est l’une des questions les plus troublantes dans le monde contemporain. Elle expose la fragilité de l’être humain qui se trouve dans une situation de changement radical et de transition tumultueuse. À cause de la violence qui est impliquée dans ce processus, le sujet plonge dans une position de vulnérabilité aiguë et la représentation de cet aspect dans la littérature et le cinéma francophones est saisissante et puissante. Notre travail considère le vécu difficile du migrant et la violence qui est exercée sur ce dernier à partir de trois grands axes ; le point de départ, le voyage et le point d’arrivée. Les auteurs et les réalisateurs qui, dans leurs œuvres, traitent de la figure du migrant ou l’incluent, révèlent la réalité complexe de l’expérience de la migration qui, dans la conscience collective occidentale, est généralement tronquée, simplifiée et/ou complètement écartée. L’étude de la représentation littéraire et filmique permet d’explorer les stratégies artistiques qui sont employées pour dire et montrer l’expérience au lecteur/spectateur et d’établir un réseau de connexions qui concrétise la souffrance et le tourment que l’Autre, pris dans le piège de la migration, subit. / Migration is one of the most disturbing and soul-searching issues in the contemporary world. It exposes the fragility of the human being who finds himself in a situation of radical change and turbulent transition. Owing to the violence involved in the process, the subject is plunged in a position of acute vulnerability and the representation of this aspect in francophone literature and cinema is striking and powerful. This work examines the difficult life of the migrant and the violence that is exerted on the latter from three main axes; the starting point or the point of departure, the voyage and the point of arrival. The authors and filmmakers who, in their works, deal with the figure of the migrant or include it, reveal the complex reality of the experience of migration which, in Western collective consciousness, is usually truncated, simplified and/or dismissed completely. The study of the literary and cinematic representation allows for the exploration of the artistic strategies employed to transmit the experience to the reader/spectator and for the establishment of a network of connections which concretises the suffering and the torment that the Other, caught in the snare of migration, endures.
953

Análise teórica de uma nova técnica de processamento de sinais interferométricos baseada na modulação triangular da fase óptica

Takiy, Aline Emy [UNESP] 30 November 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-11-30Bitstream added on 2014-06-13T20:49:10Z : No. of bitstreams: 1 takiy_ae_me_ilha.pdf: 1702331 bytes, checksum: b89d2b4960ee7bbc0e01a3a5d3e7a2be (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Neste trabalho estuda-se a interferometria laser, a qual constitui uma técnica adequada para determinar grandezas físicas com sensibilidade extremamente elevada. Basicamente, no interferômetro óptico, a informação a respeito do dispositivo sob teste é inserida na fase da luz. Utilizando-se o fotodiodo, promove-se a transferência de informação, do domínio óptico para o elétrico, no qual pode ser demodulada usando-se as várias técnicas disponíveis na literatura para detectar sinais modulados em fase. Ênfase é dada a um novo método de demodulação de fase óptica auto-consistente e de grande sensibilidade. Neste método, utiliza- se a modulação dada por uma forma de onda triangular e é baseado na análise do espectro do sinal fotodetectado, sendo capaz de estender a faixa dinâmica de demodulação a valores tão elevados quanto às dos métodos clássicos. Simulações dinâmicas computacionais de interferômetros ópticos são executadas em Simulink juntamente com este método, levando-se em consideração tensões de ruído eletrônico do tipo ruído branco, evidenciando a eficiência do método quando comparados com dados teóricos obtidos em Matlab. A validação experimental do método é realizada com o auxílio de um modulador eletro-óptico de amplitudes, cujas características de fase podem ser previstas analiticamente. Trata-se de um sensor polarimétrico baseado em cristal de Niobato de Lítio, em que a diferença de fase óptica induzida pela tensão elétrica aplicada pode ser determinada através de análise espectral, tal como o novo método descrito neste trabalho. Um interferômetro de Michelson homódino de baixo custo é implementado e a eficiência do novo método de demodulação de fase óptica é avaliada através de testes com atuadores e manipuladores piezoelétricos flextensionais, cujas características de linearidade são conhecidas... / In this work, has been done a study the laser interferometer, which is a technique for determining physical quantities with extremely high sensitivity. Basically, in the optical interferometer, information about the device under test modulates the phase of light. Using a photodiode, promotes the transfer of information from the optical domain for the electric, which can be demodulated using the various techniques available in literature to detect modulated signals in phase. Emphasis is given to a new method of phase demodulation of optical self-consistent and high sensitivity. The method employs a linear modulation given by a triangular waveform, and is based on analysis of the spectrum of the photodetected signal, being able to extend the dynamic range of the demodulation values as high as the classical methods. Dynamic computational simulations of optical interferometers are implemented in Simulink with this method, taking into account strains of electronic noise like white noise, indicating the efficiency of the method compared with theoretical data obtained in Matlab workspace. The experimental validation of the method is performed with the aid of an electro- optic amplitude modulator, whose phase characteristics can be analytically predicted. This is a polarimetric sensor based on lithium niobate crystal, in which the optical phase difference induced by electric voltage can be determined by spectral analysis, using new method described in this work. A low cost homodyne Michelson interferometer is implemented and the efficiency of the new method of optical phase demodulation is evaluated by testing with piezoelectric flextensional actuators whose characteristics of linearity are well known.The experimental results agree with theoretical analysis and reveal this method is more efficient than the classical methods
954

Rupturas e reconstruções: migração forçada e redes sociais em meio da guerra em Colômbia

Cruz, Olga Del Pilar Vásquez 06 December 2007 (has links)
Made available in DSpace on 2016-06-02T19:24:45Z (GMT). No. of bitstreams: 1 1638.pdf: 2449937 bytes, checksum: 9ada971042e6ba10bfb9815b66e9c98c (MD5) Previous issue date: 2007-12-06 / Financiadora de Estudos e Projetos / The history of Colombia is characterized by violent processes of population expulsion that date back half of the twentieth century and which has been deepened as a consequence of internal armed conflict which resumes in 90´s. Since 1985 until nowadays, 3,700,000 people have been displaced. Who is obliged to flee, leaves rural areas to the cities closest to his place of housing. However, the deepening of the conflict is forcing people continue moving to the big cities, where are greater opportunities for anonymity. Thus, considering the peculiarities of internal displacement, we proposed to characterize -from the perception of actors- the personal networks of a group of migrants by the internal armed conflict, which today live in neighborhoods of Ciudad Bolivar in Bogotá. This is, the way of the networks act, are affected and rebuilt on the migratory path. Our aim was evident if, in the same way as it happens with other types of migration, there is a logic of communication, permanence, re-configuration and organization of social networks; In addition to describe the situations that facilitate, influence or limit these processes. The methodology of research emphasized on record -in a notebook and a record- the comments made by people and the narratives during the contact with the researcher in informal and formal interviews. The configuration of personal networks was complemented with the application of a survey. As a result of search, we can say that there is a logical of networks in time to elect Bogotá as destination. Usually, relatives or acquaintances, whose migrated before - because of the violence or economic reasons- or there is a previous experience housing in Bogotá. These links are essential in processes of adaptation to city. With the coexistence in the city, displaced persons will meet neighbors, coworkers, employees of NGOs and institutions of the state, which will be adding to the range of their relationships. However, violence, fear and distrust are some factors that influence the incorporation of new ties and the preservation of ancient, affecting the dynamics and the configuration of networks / A história da Colômbia se caracteriza por violentos processos de expulsão de população que datam da metade do século XX, e que têm se aprofundado como conseqüência do conflito armado interno que recomeça na década de 90. Estatisticamente, desde o ano de 1985 até hoje são 3.700.000 pessoas que têm se deslocado. Quem está obrigado a fugir, sai das zonas rurais até os municípios mais próximos de seu lugar de moradia. No entanto, o aprofundamento do conflito obriga as pessoas a continuarem se deslocando até as grandes cidades onde são maiores as possibilidades de anonimato. Assim, considerando as particularidades do deslocamento interno, se propôs caracterizar a partir da percepção dos atores a forma como as redes pessoais de um grupo de migrantes advindos do conflito armado interno que, hoje, moram nos bairros da subprefeitura de Ciudad Bolívar, em Bogotá agem, se afetam e se reconstroem na trajetória migratória. Nosso intuito era evidenciar se, da mesma maneira como acontece com outros tipos de migração, há uma lógica de comunicação, permanência, reconfiguração e organização das redes sociais; além de descrever as situações que facilitam, condicionam ou limitam estes processos. A metodologia de pesquisa enfatizou o registro em caderno de campo e mediante gravação das observações e narrativas feitas pelas pessoas durante os contatos com a pesquisadora, em entrevistas informais e em profundidade. A configuração das redes pessoais foi complementada com a aplicação de um survey. Como resultado da pesquisa, podemos dizer que existe uma lógica de redes na hora de eleger Bogotá como destino, geralmente porque há familiares ou conhecidos que migraram antes por causa da violência ou por razões econômicas ou porque existe uma experiência prévia de moradia ou contato com Bogotá. Estes laços constituem-se chave nos processos de adaptação à cidade. Com o convívio na cidade, as pessoas deslocadas vão conhecendo vizinhos, colegas de trabalho, funcionários de ONGs ou de instituições do Estado, que vão se adicionando ao seu leque de relacionamentos. No entanto, a violência, o medo e a desconfiança são alguns fatores que condicionam a incorporação de novos laços e a conservação de antigos, afetando a dinâmica e a configuração das redes destes migrantes
955

Contribuições para o acionamento do compressor linear ressonante sem sensor de posição / Contribution to drive the resonant linear compressor without displacement sensor

Dainez, Paulo Sérgio 25 June 2010 (has links)
Made available in DSpace on 2016-12-12T17:38:37Z (GMT). No. of bitstreams: 1 Paulo Sergio Dainez - resumo.pdf: 31972 bytes, checksum: 94a24928564b90b196513e814cfe09a3 (MD5) Previous issue date: 2010-06-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In the resonant linear compressor the piston is drive by a linear actuator and a resonant mechanical spring directly in the reciprocating motion, this is a mass spring resonant system, eliminating bearing and crank of the conventional reciprocating compressors, and the friction loss has a significant reduction. The maximum displacement of the piston is regulating by the equilibration between the power supply by the actuator and the power transfer to the gas compression process. This type of the compressor is design to work at the resonant frequency of the mass spring system, in this condition the efficiency is maximum. Then the control must drive the linear actuator in the maximum displacement of the piston and adjust the drive frequency at the system resonant frequency. For enable of this process is necessary that piston position is known with precision, however the installation of a sensor have same difficulty, since the refrigeration compressor is hermetic system, and it have high pressure and temperature, with wide range of variation. This work develop the implementation of a full order linear observer to estimate the displacement and the velocity of the piston of the resonant linear compressor, and a control system able to drive the compressor in the maximum piston displacement and in the resonant frequency, and only measured a current of the linear actuator, without sensor inside de compressor. For this a nonlinear model of the compressor and a linear model with variable coefficients for the observer are develop, also a simulator of the system is develop, where the compressor model is controlled by the displacement and the velocity signals calculate by observer, demonstrated the feasibility of the proposed technique in the present work. / Nos compressores lineares ressonantes o pistão é acionado por um atuador linear e molas diretamente no sentido do seu movimento alternativo, formando um sistema massa-mola ressonante, eliminando assim os mancais mecânicos e o sistema biela e manivela dos compressores convencionais, reduzindo de forma significativa as perdas por atrito. A amplitude do deslocamento do pistão é regulada pelo equilíbrio da potência fornecida pelo atuador e a potência transferida para o processo de compressão do gás. Estes compressores são projetados para funcionar na frequência de ressonância do sistema massa-mola, nesta condição a eficiência do sistema é máxima. Assim, o controle deve acionar o atuador linear na máxima amplitude de deslocamento do pistão e ajustar a frequência de acionamento na frequência de ressonância do sistema. Para viabilizar este processo é necessário que o curso do pistão seja conhecido com precisão, porém a instalação de um sensor apresenta dificuldades, pois os compressores de refrigeração são herméticos e estão sujeitos a pressões e temperaturas elevadas e com grande faixa de variação. Este trabalho propõe a implementação de um observador de estados de ordem plena, para estimar o deslocamento e a velocidade do pistão do compressor linear ressonante, e um sistema de controle capaz de acionar o compressor no deslocamento máximo e na frequência de ressonância, medindo somente a corrente no atuador linear, sem a necessidade de sensores instalados dentro do compressor. Para isto desenvolve-se um modelo não linear do compressor e um modelo linear equivalente de coeficientes variáveis para o projeto do observador, também é desenvolvido um simulador do sistema, onde o modelo do compressor é controlado pelos sinais de deslocamento e velocidade calculados pelo observador, demonstrando a viabilidade da técnica proposta no presente trabalho.
956

Análise numérica de lajes treliçadas pré-moldadas com adição de resíduo de borracha /

Santos, Marcos Rebuá dos. January 2009 (has links)
Resumo: Neste trabalho, resultados experimentais relacionados a flechas imediatas de protótipos de lajes pré-moldadas treliçadas biapoiadas, com concreto com e sem resíduo de borracha de pneu, são comparados com resultados numéricos obtidos com base nas recomendações da NBR 6118 (ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS - ABNT, 2003) e do CEB-90 (COMITÊ EURO-INTERNACIONAL DU BÉTON - CEB, 1993). Foram feitas as seguintes análises. Na primeira, aplicaram-se as recomendações dos códigos ao elemento estrutural como um todo visando avaliar a sua rigidez; em seguida, com a expressão procedente da resistência dos materiais, foi calculada a flecha imediata. Estas modelagens numéricas estão referenciadas no texto como Branson, que representa a modelagem adotada pela NBR 6118:2003, e CEB-90. Na segunda, com o auxílio do sistema computacional ANSYS®, as expressões para o cálculo da rigidez segundo os códigos foram aplicadas aos elementos finitos que compunham os protótipos e não mais aos protótipos como um todo. Levou-se em consideração o carregamento incremental e este tipo de análise não linear gerou os resultados referenciados no texto como Branson discretizado e CEB-90 discretizado. Em uma terceira análise, com o auxílio do ANSYS®, utilizando-se o modo de carregamento incremental, aplicou-se, para cada elemento finito, a expressão do momento de inércia relativa aos estádios I ou II, dependendo do máximo momento fletor atuante no elemento e do momento de fissuração do protótipo. Os resultados obtidos foram referenciados no texto como Ansys - Estádios I e II. Para as análises mencionadas, foram utilizados os momentos de fissuração calculados, bem como os momentos de fissuração observados experimentalmente. Também foi analisado o comportamento da linha neutra. Considerando-se o Estado Limite de Serviço, os métodos de Branson, do CEB-90, do CEB-90... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work, experimental results related the immediate displacements of bi-supported lattice joist precast slab prototypes, with and without tire rubber residue in the concrete, are compared with numerical results obtained by the expressions of Branson, which is used by the brazilian standard NBR 6118 (ABNT, 2003), and by the method of CEB-90 (1993). The following analyses were made. In the first analysis, the expressions of the codes were applied for the whole structural element, obtaining its stiffness; so, with the use of the expression from the strength of materials, the immediate displacement was determined, called in this work of Branson and CEB-90. In the second analysis, with the help of the computational system ANSYS ®, the expressions for the calculation of the stiffness according to the codes were applied to the finite elements that were composing the prototypes and not more to the prototypes as a whole. The load was applied in an incremental mode, and this type of non-linear analysis produced the results called in the text of Branson discretized and CEB-90 discretized. In the third analysis, with the help of the ANSYS®, and using the incremental load, for each finite element, the expressions of the stiffness associated to the states I and II, that depends on the cracking moment and the maximum bending moment that acts in each finite element, were applied. These results were called in the text of Ansys States I and II. For the mentioned analyses, both the calculated and the experimentally observed cracking moment values were used. Also there was analysed the behavior of the neuter line. Considering the Service Limit State, the methods of Branson, of the CEB-90, the CEB-90 discretized and of Ansys States I and II presented satisfactory results, on behalf of the security, since the calculated cracking moment is used. But when the experimentally cracking moment is used... (Complete abstract click electronic access below) / Orientador: Jorge Luís Akasaki / Coorientador: José Luiz Pinheiro Melges / Banca: Renato Bertolino Junior / Banca: Roberto Chust Carvalho / Mestre
957

Clarice Lispector: criador e criaturas : uma leitura de A hora da estrela

Faria, Robson Ricardo Dal Santo [UNESP] 27 July 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-07-27Bitstream added on 2014-06-13T19:47:05Z : No. of bitstreams: 1 faria_rrds_me_sjrp.pdf: 676403 bytes, checksum: b50c3fe34645bb7639621018162d3df2 (MD5) / Este trabalho é um estudo de A hora da estrela de Clarice Lispector. Nele buscou-se identificar, no campo do enunciado, a presença do mito, principalmente do mito judaico-cristão, com o intuito de entender como essas narrativas mitológicas são (re)construídas no texto clariciano. Para tanto, tomou-se por base e como norteadora da análise a teoria arquetípica de Northrop Frye. Com a identificação desse substrato mítico em A hora da estrela, observou-se que o mesmo surge deslocado no enredo, por meio de inversões, ironias, paráfrases, etc. Também foi possível identificar, na tragetória da protagonista uma releitura da Via Crucis percorrida pelo principal personagem do cristianismo - Jesus. Ao final, como sugestão de percurso interpretativo a ser trilhado objetivando entender as conseqüências do deslocamento do substrato mítico no livro, indicamos o estudo de Luigi Pirandello sobre o Humor. / This research is a study of A hora da estrela by Clarice Lispector. In this fetched up identify, in the field of enunciated the presence of the myth, mainly the judaicchristian myth, with the intention to understand how this mythologics narratives are (re)constructed in the Clarice Lispector s text. Therefore, took up for basis and orientation of the analysis the Northrop Frye archetypical theory. With the identification of that mythic substratum in A hora da estrela, observed up that the same is displaced in the plot, through of inversions, ironies, paraphrases, and so on. Also it was possible identify, in the life story of protagonist a reread of the Via Crucis went through by personage principal of christianity - Jesus. At the end, as interpretative suggestion course with the objective to understand the consequences of mythic displacement in the book, we have indicated the study by Luigi Pirandello about Humor.
958

Český Rudolec ve 20. století / Český Rudolec in 20th century

MĚRTLOVÁ, Lucie January 2009 (has links)
Diploma-work themed {\clqq}Český Rudolec in the 20th century`` is basically dedicated to the commune of Český Rudolec, its neigbourhoods and events, that influenced its life. Diploma-work starts with brief historical overview of development of Český Rudolec from it´s beginnings till the start of 20th century. The era of years 1900 {--} 1918 and the age of the {\clqq}first Czechoslovak republic`` follows. Focus of this diploma-work rests on description of event in 30s and 40s of the 20th century. Main attention is paid to events of 1938 and consecutive germanic occupation of Czech border regions, furthermore to the year 1945, end of the war, along with serious theme of displacement of residents with German nationality and consecutive re-settlement of commune. Next chapter is dedicated to years 1948 {--} 1989 and to development after year 1989. Following chapters of diploma-work are dedicated to important personalities of cummune and its region, to fates of Jewish residents, sights, especially to the castle, and to schools in Český Rudolec. There are appendixes at the end of diploma-work, containing mainly contemporary photos and postcards for illustration and futher refinements of the diploma-work. This diploma-work results from study of national and regional literature and conterporary sources (archive materials, communal chronicle, memories of eyewitnesses).
959

Hodnocení vegetačních pozůstatků někdejšího osídlení ve vybrané příhraniční oblasti / Evaluation of vegetation remnants of former settlements in selected border areas

KALNÁ, Eva January 2010 (has links)
Eva Kalná, 2010:Evaluation of vegetation remnants of former settlements in selected border areas. It was chosen region Zhůří for this work, which is one of the displaced villages at Šumava Mountains, which was part of the Dobrá Voda military training area. First, the work is devoted to the history of the village and then to changes in vegetation both directly and indirectly influenced by humans. The part of theme of this paper is primarily exploring areas of interest in terms of plant species, providing evidence of former settlements and making photographs and map outputs for each species found. The next theme is the evaluate of using the area from 1949 to the present, which over decades has fundamentally changed. Work also focuses on comparisons between the state of use from the 1949 today state habitat.
960

Análise comparativa de métodos de ensaio para caracterização do comportamento mecânico de concreto reforçado com fibras. / Comparative analysis of test methods for the characterization of the mechanical behavior of fiber-reinforced concrete.

Renan Pícolo Salvador 20 December 2012 (has links)
O emprego de fibras para reforço de concreto é uma técnica bastante conhecida e estudada mundialmente. As mais conhecidas e estudadas são as fibras de aço, embora utilização das macrofibras poliméricas esteja amplamente difundida no mercado brasileiro. Entretanto, a caracterização do comportamento mecânico de concretos reforçados com essas macrofibras ainda deve ser mais bem avaliada. Dentre os diversos métodos utilizados para essa finalidade, os ensaios realizados com sistema fechado de controle de velocidade de deslocamento fornecem resultados mais confiáveis. A principal vantagem conferida por esse sistema está na avaliação desses compósitos em baixo nível de fissuração com maior acurácia. O desempenho desses compósitos foi estudado segundo as normas ASTM C1609 (2010), ASTM C1399 (2010) e EN 14651 (2007) e o método JSE-SF4 (1984). Os quatro procedimentos prescrevem ensaios de flexão de corpos-de-prova prismáticos para determinação da resistência residual pós-fissuração e da tenacidade. Os procedimentos americanos e o método japonês prescrevem configuração de aplicação de carga por dois cutelos superiores, posicionados sobre o terço médio do corpo-de-prova. Já a configuração do método europeu é de aplicação de carga por apenas um cutelo superior, centralizado em relação ao vão de ensaio, com corpos-de-prova com entalhe na face inferior. Foram estudadas uma macrofibra de polipropileno, nas dosagens de 0,22, 0,33, 0,50, 0,66, 0,82 e 1,0% em volume em três matrizes de concreto, com resistências médias à compressão de 30, 35 e 40MPa, e uma fibra de aço, nas dosagens de 0,19, 0,32 e 0,45% em volume em uma matriz de resistência média à compressão de 35MPa. Foi observado que a utilização da velocidade de deslocamento do corpo-de-prova como parâmetro de controle do ensaio forneceu boas condições de avaliação do compósito, devido à redução da instabilidade pós-pico. Com isso, a determinação da resistência residual do compósito nos níveis iniciais de deslocamento e fissuração da matriz foi mais bem caracterizada. Pela análise e comparação dos resultados, foram formuladas equações para estabelecer correlações entre os diferentes métodos de ensaio. Com o modelo de regressão utilizado na análise estatística foi possível verificar que a resistência à compressão da matriz, o tipo e o teor de fibra são as variáveis independentes que mais influenciam os resultados de resistência residual. Foi necessário estabelecer correlações para cada tipo de fibra separadamente, pois o comportamento de slip-softening ou de slip-hardening influencia as funções obtidas. / The use of fibers for concrete reinforcing is a very common practice, used all over the world. Steel fibers are the most common and studied, although synthetic macrofibers are in very common use in the Brazilian market. However, the evaluation of the mechanical behavior of concrete reinforced with this type of fiber must be evaluated. A broad range of tests is available for this purpose. Tests performed under closed-loop displacement control provide more reliable results. The main advantage of that system is in the evaluation of the composite at low levels of crack opening with higher accuracy. In this study, the performance of these composites was examined according to the standard test methods ASTM C1609 (2010), ASTM C1399 (2010), EN 14651 (2007) and JSCE-SF4 (1984). These four methods prescribe flexural tests in prismatic specimens for the determination of post-crack residual strength and toughness. The American and the Japanese test methods prescribe four-point bending tests, while the European test method prescribes three-point bending tests and specimens with a notch in the bottom face. Two fibers were analyzed: a polypropylene macrofiber, used in the dosages of 0.22, 0.33, 0.50, 0.66, 0.82 and 1.0 in volume percentage, in three concrete matrices with average compressive strengths of 30, 35 and 40MPa, and a steel fiber, in the dosages of 0.19, 0.32 and 0.45 in volume percentage, in one concrete matrix of average compressive strength of 35MPa. It was observed that the use of the net displacement of the specimen as the parameter to control the load application provided good conditions for the evaluation of the mechanical behavior of the composite, due to the reduction of post-peak instability. Therefore, the determination of the residual strength of the composite in the initial levels of displacement and cracking of the matrix was better achieved. From the comparative analysis of the results, equations were developed to establish a correlation among the test methods. Based on the model used in the statistical analysis, the main independent variables that influence the results of residual strength are the compressive strength of the concrete matrix, the type and the content of the fiber. The equations were obtained separately according to the fiber type, because the behavior of slip-hardening or slip-softening influence the correlations.

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