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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.
1

Estudo das alternativas de uso da fibra de vidro sem características álcali resistente em elementos construtivos de cimento Portland / Study of alternatives to use de glass fibers without alkali-resistant characteristics in the cement composite products for civil construction

Peruzzi, Antônio de Paulo 13 December 2007 (has links)
As fibras de vidro são usadas há alguns anos com a finalidade de melhorar a resistência à tração e ao impacto de compósitos cimentícios. Mas, os álcalis do cimento Portland atacam essas fibras causando a degradação de suas propriedades mecânicas. Para contornar essa degradação, há alguns anos, foram desenvolvidas as fibras álcalis-resistente (AR) que, embora tenham apresentado melhor desempenho que as fibras de vidro convencionais, ainda apresentam perda de desempenho com o tempo. Esse trabalho trata do desenvolvimento de um novo tipo de fibra na forma de telas, a partir das fibras de vidro convencionais, usando uma impregnação de PVC como barreira para impedir o ataque químico dos álcalis do cimento. A análise da eficiência dessas telas em relação à durabilidade foi feita por meio de processo de envelhecimento acelerado e, a seguir, foram estudados os vários tipos de aplicação delas em elementos construtivos à base de matrizes cimentícias concomitantemente como o uso de barras de GFRP. Como resultado final comprovou-se a eficiência da resina desenvolvida na pesquisa para impregnação das fibras em relação à sua durabilidade frente ao meio alcalino do cimento Portland e a adequação do uso das telas impregnadas com essa resina em diversos tipos de produtos de matrizes cimentícias para construção civil. / Glass fibers are used since several years to improve the tensile and impact strengths of cement composites. But, the alkalis from Portland cement attack the glass fibers causing the deterioration of its mechanical properties. For overcome this degradation, some years ago, were developed the fibers alkali-resistant (AR) which, although presented as the best performance fiber glass conventional, still show a loss of performance over time. This work deals with the development of a new type of fiber in the form of mesh, from conventional glass staple fibers, using a PVC impregnation as barrier to hinder the chemical attack alkalis them it cement to these. The analysis of the efficiency of these fibers in relation to the durability was made by means of process accelerated ageing and, next, concomitantly studied some types of application of these fibers in constructive elements to the cements matrix with the use of bars of GFRP. The final result showed tha the resin developed in this work is efficient how coating of conventional fibers to get durability on the alkaline environment and the mesh impregnated with this resin are appropriates of the use in many kinds of products to construction made from cements matrixes.
2

Estudo das alternativas de uso da fibra de vidro sem características álcali resistente em elementos construtivos de cimento Portland / Study of alternatives to use de glass fibers without alkali-resistant characteristics in the cement composite products for civil construction

Antônio de Paulo Peruzzi 13 December 2007 (has links)
As fibras de vidro são usadas há alguns anos com a finalidade de melhorar a resistência à tração e ao impacto de compósitos cimentícios. Mas, os álcalis do cimento Portland atacam essas fibras causando a degradação de suas propriedades mecânicas. Para contornar essa degradação, há alguns anos, foram desenvolvidas as fibras álcalis-resistente (AR) que, embora tenham apresentado melhor desempenho que as fibras de vidro convencionais, ainda apresentam perda de desempenho com o tempo. Esse trabalho trata do desenvolvimento de um novo tipo de fibra na forma de telas, a partir das fibras de vidro convencionais, usando uma impregnação de PVC como barreira para impedir o ataque químico dos álcalis do cimento. A análise da eficiência dessas telas em relação à durabilidade foi feita por meio de processo de envelhecimento acelerado e, a seguir, foram estudados os vários tipos de aplicação delas em elementos construtivos à base de matrizes cimentícias concomitantemente como o uso de barras de GFRP. Como resultado final comprovou-se a eficiência da resina desenvolvida na pesquisa para impregnação das fibras em relação à sua durabilidade frente ao meio alcalino do cimento Portland e a adequação do uso das telas impregnadas com essa resina em diversos tipos de produtos de matrizes cimentícias para construção civil. / Glass fibers are used since several years to improve the tensile and impact strengths of cement composites. But, the alkalis from Portland cement attack the glass fibers causing the deterioration of its mechanical properties. For overcome this degradation, some years ago, were developed the fibers alkali-resistant (AR) which, although presented as the best performance fiber glass conventional, still show a loss of performance over time. This work deals with the development of a new type of fiber in the form of mesh, from conventional glass staple fibers, using a PVC impregnation as barrier to hinder the chemical attack alkalis them it cement to these. The analysis of the efficiency of these fibers in relation to the durability was made by means of process accelerated ageing and, next, concomitantly studied some types of application of these fibers in constructive elements to the cements matrix with the use of bars of GFRP. The final result showed tha the resin developed in this work is efficient how coating of conventional fibers to get durability on the alkaline environment and the mesh impregnated with this resin are appropriates of the use in many kinds of products to construction made from cements matrixes.
3

Comportamento das fibras de vidro convencionais em matriz de cimento Portland modificada com látex e adição de sílica ativa. / Behavior of conventional glass fibers in matrix of Portland cement modified with latex and with the addition of silica fume.

Peruzzi, Antônio de Paulo 22 July 2002 (has links)
As argamassas e concretos de cimento Portland são materiais de construção duráveis, relativamente baratos que, embora apresentem boa rigidez e adequada resistência à compressão, têm outras propriedades deficientes, tais como: resistência à tração, ao impacto, à fadiga, além de baixa tenacidade e ductilidade. Uma considerável melhora destas propriedades pode ser obtida com adição de fibras, em quantidades adequadas, na composição destes materiais. A utilização de fibra de vidro convencional (tipo E) no reforço das argamassas de cimento Portland, pode ser viável uma vez contornado o ataque do meio alcalino à fibra, principalmente o hidróxido de cálcio Ca(OH)2, produzido na hidratação do cimento. No presente trabalho foi obtida uma menor intensidade de ataque alcalino às fibras de vidro E, por meio da modificação com látex Estireno Butadieno, da adição de sílica ativa em substituição ao cimento Portland e da utilização de ambos concomitantemente. Outro procedimento utilizado, visando uma maior durabilidade das fibras de vidro, foi a proteção da superfície desta fibra com uma película de látex Estireno Butadieno e de uma mistura deste látex e sílica ativa. A eficiência de um e outro procedimento foi verificada por meio da comparação dos resultados de ensaio à tração e flexão, em amostras submetidas a processo de hidratação convencional e acelerado e observações pro meio de microscopia óptica. / Portland cement mortar and concrete are durable building materials, relatively cheap and, despite they display a good rigidity and an adequate compressive strength, they have other deficient properties such as tensile strength, impact, fatigue, beyond low toughness and ductility. A considerable improvement of these properties can be obtained adding fibers, in adequate quantities, in the composition of the materials. The use of conventional glass fiber (E-glass) in the reinforcement of Portland cement mortar can be possible if the attack of the alkaline environment, produced by cement hydration (chiefly by calcium hydroxide), to the fiber is controlled. In this work, a lesser intensity of alkaline attack on the E-glass fibers was succeded through the modification of the Portland cement matrix by styrene butadiene latex, the addition of silica fume or through the utilization of both additives at the same time. Another proceeding, aiming at a greater durability of the E-glass, has been the protection of the fiber surface with a styrene butadiene latex coating or with a mixture of this same latex and silica fume. The efficiency of each proceeding was verified by the comparison of tensile strength and flexural strength in samples submitted to accelerate and conventional hydration processes and by the observation of the interface glass/matrix with optical microscopy.
4

Comportamento das fibras de vidro convencionais em matriz de cimento Portland modificada com látex e adição de sílica ativa. / Behavior of conventional glass fibers in matrix of Portland cement modified with latex and with the addition of silica fume.

Antônio de Paulo Peruzzi 22 July 2002 (has links)
As argamassas e concretos de cimento Portland são materiais de construção duráveis, relativamente baratos que, embora apresentem boa rigidez e adequada resistência à compressão, têm outras propriedades deficientes, tais como: resistência à tração, ao impacto, à fadiga, além de baixa tenacidade e ductilidade. Uma considerável melhora destas propriedades pode ser obtida com adição de fibras, em quantidades adequadas, na composição destes materiais. A utilização de fibra de vidro convencional (tipo E) no reforço das argamassas de cimento Portland, pode ser viável uma vez contornado o ataque do meio alcalino à fibra, principalmente o hidróxido de cálcio Ca(OH)2, produzido na hidratação do cimento. No presente trabalho foi obtida uma menor intensidade de ataque alcalino às fibras de vidro E, por meio da modificação com látex Estireno Butadieno, da adição de sílica ativa em substituição ao cimento Portland e da utilização de ambos concomitantemente. Outro procedimento utilizado, visando uma maior durabilidade das fibras de vidro, foi a proteção da superfície desta fibra com uma película de látex Estireno Butadieno e de uma mistura deste látex e sílica ativa. A eficiência de um e outro procedimento foi verificada por meio da comparação dos resultados de ensaio à tração e flexão, em amostras submetidas a processo de hidratação convencional e acelerado e observações pro meio de microscopia óptica. / Portland cement mortar and concrete are durable building materials, relatively cheap and, despite they display a good rigidity and an adequate compressive strength, they have other deficient properties such as tensile strength, impact, fatigue, beyond low toughness and ductility. A considerable improvement of these properties can be obtained adding fibers, in adequate quantities, in the composition of the materials. The use of conventional glass fiber (E-glass) in the reinforcement of Portland cement mortar can be possible if the attack of the alkaline environment, produced by cement hydration (chiefly by calcium hydroxide), to the fiber is controlled. In this work, a lesser intensity of alkaline attack on the E-glass fibers was succeded through the modification of the Portland cement matrix by styrene butadiene latex, the addition of silica fume or through the utilization of both additives at the same time. Another proceeding, aiming at a greater durability of the E-glass, has been the protection of the fiber surface with a styrene butadiene latex coating or with a mixture of this same latex and silica fume. The efficiency of each proceeding was verified by the comparison of tensile strength and flexural strength in samples submitted to accelerate and conventional hydration processes and by the observation of the interface glass/matrix with optical microscopy.
5

A utilização de GRC na renovação de edifícios : caso de estudo: centro de I&D do IPCA

Pereira, Ana Cláudia Costa January 2013 (has links)
Tese de Mestrado Integrado. Mestrado em Engenharia Civil (Construções). Faculdade de Engenharia. Universidade do Porto. 2013
6

Koll på SOX : En fallstudie av implementeringen av SAP GRC Version 10  inom delar av ABB-koncernen

Öberg, Jacob, Björmsjö, Lars January 2012 (has links)
Magisteruppsats i företagsekonomi inom ramen för Civilekonomprogrammet med företagsekonomisk inriktning vid Internationella Handelshögskolan i Jönköping Titel                                   Koll på SOX – En fallstudie av implementeringen av SAP GRC Version 10 inom delar av ABB-koncernen. Författare                           Lars Björmsjö, Jacob Öberg Handledare                       Gunnar Rimmel Ämnesord                         GRC, intern kontroll, SAP, Sarbanes-Oxley Act Sammanfattning Bakgrund (och problem): Med de redovisningsskandalerna som skakat den finansiella världen i början av 2000-talet, har lagstiftningen stramats åt för företag för att förhindra att detta inträffar igen. Lagar som SOX ger tydliga direktiv på hur företagen ska stärka sina interna kontroller. Att efterleva SOX är en kostsam historia då, de ställer hårda krav på intern kontroll samt system för att hantera de ökade kontrollerna. Problembakgrunden till denna uppsats bygger på kraven att efterleva SOX och hur ett internationellt företag kan använda sig av ett IT-verktyg som SAP GRC för att klara av de hårdare kraven. Syfte: Syftet med detta examensarbete är att utföra en fallstudie på hur processen bakom implementeringen av SAP GRC version 10 ser ut i ett multinationellt företag som ABB och vilken roll SOX har i sammanhanget Avgränsningar: Författarna har valt att avgränsa sig till att enbart titta på implementeringen av SAP GRC, och tittar då inget på andra aktörers liknande produkter. Vidare har författarna valt att bara titta på implementeringen inom det brittiska ABB.  Metod: Studien har ett kvalitativ angreppssätt. Studien är en fallstudie vilket innebär att personlig kontakt i form av telefonintervjuer har varit enda metoden för att samla in data till empirin. Resultat/Slutsats: Författarnas slutsats av undersökningen fastställs i att SOX har en väldigt viktig roll i implementeringen av SAP GRC, det är anledningen till implementeringen. Vidare har det framkommit att implementeringen är ett väldigt omfattande arbete, som är mycket kostsamt i både monetära mått samt tid. Dock är detta, det mest effektiva och kostnadseffektiva sättet att efterfölja SOX från ett ABB perspektiv Diskussion: Författarna ser ett par områden för förbättring inom användningen av GRC på ABB för att få ut det mesta av verktyget, samt att effektivera hanteringen av risker. Vidare ser författarna förslag till vidare forskning. I dag finns det ingen direkt forskning på konceptet eller verktyget GRC, författarna finner det intressant om en vetenskapligt grundad definition skulle undersökas. / Master Thesis in Business Administration within the Civilekonomprogram at Jönköping International Business School Title                                   Keeping track of SOX – A case study of the implementation of SAP GRC Version 10 in parts of the ABB Group Authors                              Lars Björmsjö, Jacob Öberg Tutor                                                        Gunnar Rimmel Subject terms            GRC, internal control, SAP, Sarbanes-Oxley Act Abstract Background (and problem): In the reflections of the accountings scandals that occurred in the beginning of this millennium, legislations have tightened to prevent this kind of event to reoccur. Legislations like SOX provide clear directives on how companies should strengthen their internal controls. Compliance with SOX is a costly affair when, they place heavy demands on internal controls and systems to manage the increased controls. Problem discussion to this thesis is based on the requirements to comply with SOX and how an international company can use a tool like SAP GRC to meet the stricter requirements  Purpose: The purpose of this thesis is to conduct a case study on how the process behind the implementation of SAP GRC version 10 looks in a multi-national company such as ABB and the role played by SOX in the implementation process. Delimitations: The authors have chosen to delimitate thesis merely to look at the implementation of SAP GRC, and do not look at other players at the market, nor their GRC solutions. Furthermore, the authors have chosen to only look at the implementation of SAP GRC at ABB in the United Kingdom. Method: The study has only a qualitative approach. The study is a case study which means that personal contact in the form of telephone interviews has been the only method to gather data for empirical choose of the authors. Results and Conclusions: The authors' conclusion of the study acknowledges that SOX has a very important role in the implementation of SAP GRC, and is the main reason for the implementation. Furthermore, it has emerged that the implementation is a very comprehensive work, which is very costly in both monetary and time measures. However the authors have concluded that implementing SAP GRC is the most efficient and cost effective way to comply with SOX from an ABB perspective. Discussion: According to the authors opinion there are a few areas for improvement in the use of GRC at ABB, in order to get the most out of the tool and to streamline the management of risks. Due to the lack of current research within the field, the authors would find it very interesting if a scientifically based definition of GRC would be investigated.
7

A fibra de vidro em matrizes poliméricas e cimentícias e seu uso estrutural em construção civil : o estado-da-arte. / Glass fiber in polymeric or cimenticious matrix and their structural use in civil construction the state-of-art.

Ortenzi Junior, Altibano 25 July 2007 (has links)
Made available in DSpace on 2016-06-02T20:09:07Z (GMT). No. of bitstreams: 1 DissAOJ.pdf: 6192010 bytes, checksum: fa94e00175e6f6ea0adcf64f7dcaee5f (MD5) Previous issue date: 2007-07-25 / Financiadora de Estudos e Projetos / This dissertation deals with the use of fiberglass as a concrete addition, in order to improve its mechanical properties such as better crack distribution, or as polymer reinforcement, in order to form a composite to be externally or internally used as reinforcement to other material as concrete or masonry or to use itself as a structural member. The literature review presented is believed to achieve the current state-of-art of the fiberglass use in civil construction applications. Next, usual approaches to dimensioning structural members in GFRP are presented. Construction systems and processes using this material are assessed focused to civil construction. Themes as the technology spread up, Brazilian applications and eventual difficulties are focused. With this research one expects to approach the text to the state-of-art up today. / Essa dissertação trata da utilização da fibra de vidro de duas formas distintas. A primeira como uma adição ao concreto para melhorar suas propriedades mecânicas num elemento estrutural qualquer, visando minimizar a propagação de fissuras por diversas ações. A segunda forma como reforço de polímeros diversos, os quais dão origem a elementos estruturais ou componentes de reforço estrutural interno ou externo de estruturas de concreto, em complemento ou substituição ao aço. É feita a revisão bibliográfica sobre as pesquisas e aplicações que representam hoje o estado-da-arte do uso desses materiais em construção civil. Em seguida, enumeram-se alguns processos de cálculo usuais para esse sistema construtivo. Posteriormente, são apresentados diversos exemplos de aplicação que fazem uso da fibra de vidro. do GRC ou dos GFRP como componentes estruturais, com enfoque para a construção civil. São abordados aspectos relativos à disseminação da tecnologia, aplicações no Brasil e dificuldades a serem transpostas. Com essa pesquisa espera-se aproximar o texto ao estadoda- arte até hoje.
8

An enterprise systems perspective to GRC IS implementation process

Spanaki, Konstantina January 2014 (has links)
Governance, Risk and Compliance (GRC) Information Systems (IS) as an integrated technology has been introduced recently to facilitate the demanding operational and financial environment of the enterprises. The implementation process and the adoption of such systems is considered as a significant parameter influencing the success of operational performance and financial governance and could support the competitive advantage practices within the organisations. However, GRC literature is limited regarding the analysis of the implementation and adoption success. Therefore, there is a need for further research and contribution about these systems and more specifically their implementation process. Consequently, this investigation and analysis can provide an insight of this process by examining the aspects of the implementation, the lifecycle phases followed and the enterprise value drivers in each of these phases. Therefore, a framework was developed for structuring the analysis of this implementation including all these three elements as these were provided by the theoretic background. The empirical context of this research includes three field investigation studies based on the experience of key implementation stakeholder groups as participants. These investigation studies were analysed using thematic techniques following an interpretative qualitative analysis approach. It was proved that organisations have, directly or indirectly, followed specific lifecycle phases when they implement GRC systems as these are also described in the framework. Also they should consider specific aspects about the GRC systems and enterprise value drivers for the different lifecycle phases but also for a holistic approach of the implementation process. Hence new GRC implementation projects can use the phases and the analysis of these elements to facilitate and ease their decision-making and strategic planning before launching the implementation project. The analysis of the GRC implementation proved that a strict GRC environment can be established in the organisations through the successful implementation of a GRC technology. The implementation process of such technologies would require a preparation for the organisational environment in order the implementation project to succeed the GRC goals and the system to be integrated and optimised harmoniously within the enterprise environment. This study provides insight of how this implementation projects could be planned and developed and gives a directive blueprint for preparing organisations hosting such technological initiatives. The results of all field investigation phases, which can be considered as the contributions to theory and practice of this research, can have twofold implications: initially the development of a theoretical framework based on enterprise systems theories, and also an analysis of the GRC implementation process in specific. The framework is designed to structure the analysis of the GRC implementation aspects, the lifecycle phases and the enterprise value drivers of the GRC implementation process. This framework is used for visualising and structuring a specific analysis of the GRC adoption and success, and therefore this analysis can be used by practitioners and researchers to further evaluate and analyse this process. Furthermore, organisations can use this analysis for decision-making processes; as this analysis can provide a primary view for the implementation projects.
9

The History of the Geelong Regional Commission.

McLean, Graham Alwin, mikewood@deakin.edu.au January 2005 (has links)
This thesis is the first systematic history of the Geelong Regional Commission (GRC), and only the second history of a regional development organisation formed as a result of the growth centres policy of the Commonwealth Labor Government in the first half of the 1970s. In particular, the thesis examines the historical performance of the GRC from the time of its establishment in August 1977 to its abolition in May 1993. The GRC Commissioners were subject to ongoing criticism by some elements of the region's political, business, rural and local government sectors. This criticism focused on the Commissioners' policies on land-use planning, their interventionist stance on industrial land development, major projects and industry protection and their activities in revitalising the Geelong central business district. This thesis examines these criticisms in the light of the Commission's overall performance. This thesis found that, as a statutory authority of the Victorian Government, the GRC was successful over its lifetime, when measured against the requirements of the Geelong Regional Commission Act, the Commission's corporate planning objectives and performance indicators, the corporate performance standards of private enterprise in the late 1990s, and the performance indicator standards of today's regional economic development organisations in the United States of America, parts of the United Kingdom and Australia. With the change of Government in Victoria in October 1992 came a new approach to regional development. The new Government enacted legislation to amalgamate six of the nine local government councils of the Geelong region and returned regional planning responsibilities to the newly formed City of Greater Geelong Council. The new Government also made economic development a major objective of local government. As a result, the raison d'etre for the GRC came to an end and the organisation was abolished.
10

Contribuição ao estudo das propriedades dos materiais cimentícios reforçados com fibras de vidro (Glass Fibre Reinforced Cement - GRC) / Contribution to the study of properties of glass fibre reinforced cement - GRC

Lameiras, Rodrigo de Melo January 2007 (has links)
Os materiais cimentícios são materiais frágeis que apresentam resistências à tração e capacidades de deformação muito baixas. Uma das formas de contornar a fragilidade destes materiais é a utilização de fibras curtas, descontínuas e dispersas. Um exemplo destes materiais cimentícios são os produzidos com fibras de vidro, comumente denominados pela sigla GRC. Apesar dos diversos avanços apresentados na tecnologia do GRC, ele ainda apresenta uma degradação significativa das suas propriedades ao longo do seu envelhecimento. Além disso, por ser um material que começou a ser produzido em escala industrial há pouco tempo no Brasil, há uma carência de pesquisas que caracterizem os GRCs produzidos com materiais locais. Portanto, esta pesquisa veio com o objetivo geral de avaliar o GRC produzido com fibras de vidro álcali-resistente (tipo AR) e com os materiais disponíveis comercialmente na cidade de Porto Alegre com relação as suas propriedades mecânicas e durabilidade. Mais especificamente, estudou-se a influência do tamanho das fibras (35mm e 17,5mm), da adição de sílica ativa (5%) e metacaulim (5%, 10% e 15%), da relação agregado/cimento (1,00 e 1,10) e da idade (28, 42, 49 e 56 dias). As propriedades estudadas foram: limite de proporcionalidade (PEL), módulo de ruptura (MOR), índices de tenacidade (I5, I10 e I30), módulo de elasticidade na flexão (MEF), absorção de água (ABS), massa especifica (MES) e porosidade aparente (PAP). Além disso, utilizou-se um método acelerado de ataque em água a 50°C, em diversos períodos de ataque (14, 21 e 28 dias), para estudar o efeito do envelhecimento nas propriedades mecânicas do GRC. Os resultados mostraram que, enquanto algumas propriedades são majoritariamente dependentes da matriz, outras são fundamentalmente dependentes das propriedades do reforço. Apesar do aumento das fibras provocar melhorias na resistência última e na capacidade de absorção de energia do material, ele também gera pertubação naquelas propriedades que as características da matriz são mais relevantes devido ao fato das fibras dificultarem o adensamento do GRC. Com o uso de elevados teores de metacaulim, os compósitos produzidos com fibras curtas apresentaram MOR e índices de tenacidade elevados (também obtidos com fibras longas), mantendo o efeito benéfico do uso deste tamanho de fibras nas propriedades que dependem mais das matrizes. As propriedades majoritariamente dependentes das características das fibras (MOR, I5, I10 e I30) se mostraram muito sensíveis ao ataque. Ademais, o uso das adições pozolânicas não se mostrou capaz de reter tais propriedades para os tempos estudados. / The cementitious materials are fragile materials that show low tensile strengths and low capacity of deformation. One way of dealing with the fragility of these materials is the utilization of short, discontinuous and disperse fibres. One of these cementitious materials is the one usually called by the term GRC. Despite the advances of the GRC technology, this material shows high degradation of its properties throughout the life cycle. Besides that, the fact of being a material which has recently been produced in Brazil on a industrial scale, there is an enormous lack on researches about GRC produced with local materials. Therefore, this research was envisioned with the main objective of evaluating the GRC properties produced with alkali-resistent glass fibres (AR type) and with materials commercially available in Porto Alegre, analyzing its mechanical properties and durability. Specifically, it studied the influence of fibre length (35 mm and 17,5 mm), of silica fume (5%) and metakaolin addition (5%, 10% and 15%), of aggregate/cement relation (1,00 and 1,10) and of the age (28, 42, 49 and 56 days). The measured properties were: proportional limit (PEL), modulus of rupture (MOR), toughness indexes (I5, I10 and I30), modulus of elasticity in bending (MEF), water absorption (ABS), bulk density (MES) and apparent porosity (PAP). In addition, the mechanicals properties of GRC under the effect of ageing (stored in water at 50°C to accelerate the ageing) were investigated where the test were carried out after 14, 21 and 28 days of the accelerated ageing. The results showed that while some properties are mainly influenced by the matrix properties (PEL, MEF, ABS, MES and PAP), others are basically dependent on the fiber reinforcement properties (MOR, I5, I10 and I30). Despite the fact that GRC produced with greater fibre length showed increases at MOR and in energy absorption capacity, it lead to losses of those properties that are mainly influenced by the matrix because it is more difficult to consolidate this GRC. Furthermore, the addition of high contents of metakaolin in composites produced with short fibres leads to MOR and toughness indexes to the higher levels found (gotten with long fibres), keeping the benefic effect of using short fibres at the properties that are basically function of the matrix properties. The MOR, I5, I10 and I30 decreased when the GRC suffer accelerated ageing. The results also showed that the use of pozzolanic additions wasn't able to retain the mechanical properties of GRC throughout time

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