Shear behaviour of steel-fibre-reinforced concrete simply supported beams

The structural behaviour of steel-fibre-reinforced concrete beams was studied using non-linear finite-element analysis and existing experimental data. The work aim was to examine the potential of using steel fibres to reduce the amount of conventional transverse steel reinforcement without compromising ductility and strength requirements set out in design codes. To achieve this, the spacing between shear links was increased while steel fibres were added as a substitute. Parametric studies were subsequently carried out and comparisons were also made with BS EN 1992-1-1 predictions. It was concluded that the addition of steel fibres enhanced the load-carrying capacity and also altered the failure mode from a brittle shear mode to a flexural ductile one. The provision of fibres also improved ductility. However, interestingly it was found that adding excessive amounts of fibres led to a less-ductile response. Overall, the study confirmed the potential for fibres to compensate for a reduction in conventional shear reinforcement.

Histoire, littérature et subversion dans Le Bulletin des agriculteurs (1940-1959)

Le Bulletin des agriculteurs existe depuis 1918 et a eu une incidence considérable sur la population rurale du Québec.Le présent mémoire porte sur la subversion dans douze récits fantastiques publiés dans la revue entre 1940 et 1959. Ce mémoire est divisé en trois chapitres distincts.Le premier relate la petite histoire de la revue. À ses débuts, en 1918,Le Bulletin des agriculteurs est une revue purement agricole qui n'a d'autre but que celui d'informer ses abonnés. Mais dès 1936, la revue adopte le style revue et apporte à ses nombreux lecteurs, en plus de l'information générale, des chroniques féminines, des articles humoristiques et des récits de fiction. Ce sont ces derniers qui sont à l'origine de ce mémoire.Le deuxième chapitre insistera sur l'aspect théorique de l'étude. Dans un premier temps, nous avons fait la typologie de tous les récits de fiction parus dans la revue entre 1934 et 1984 les classant par genre et par sous-genre. Dans un deuxième temps, nous avons étudié le fantastique et son potentiel subversif. Enfin, dans un troisième temps, nous avons identifié l'idéologie qui prévalait au Québec rural dans les années quarante et cinquante.Le troisième chapitre est consacré exclusivement à la recherche de subversion dans les douze contes fantastiques sélectionnés afin d'en faire une lecture sociocritique.

The Ms. Parma 1959 in the context of portuguese hebrew illumination

Tese de mestrado, Arte, Património e Teoria do Restauro, Universidade de Lisboa, Faculdade de Letras, 2011

Modelos de dinâmica da Terra aplicados à geologia de Portuga l: relevância da experimentação análoga no ensino e na divulgação da geologia

Tese de doutoramento, Geologia (Geodinâmica Interna), Universidade de Lisboa, Faculdade de Ciências, 2014

Genesis of the brecciated rocks from mid atlantic ridge hydrothermal systems : Lucky Strike (37º50’N) and Menez Gwen (37º50’N)

Tese de doutoramento, Geologia (Metalogenia), Universidade de Lisboa, Faculdade de Ciências, 2014

A Student Composers' Recital, May 7, 1959 8:30pm

Concert program for A Student Composers' Recital, May 7, 1959

U.W. Percussion and Steel Drum Ensembles, June 2, 2005

Concert Program for U.W. Percussion and Steel Drum Ensembles

Winston Churchill and the General Strike

Exploring the myths and legends which surround Churchill's role in the 1926 General Strike this places his involvement in the events of that year within the context of his views of sympathy strikes from before the Great War. The continuing importance of these views is shown to explain the marked contrasts between Churchill's approach to the General Strike in May 1926 and his efforts to find a way to resolve the coal dispute which dragged on throughout the year.

Microstructure, mechanical properties and chemical degradation of brazed AISI 316 stainless steel/alumina systems

The main aims of the present study are simultaneously to relate the brazing parameters with: (i) the correspondent interfacial microstructure, (ii) the resultant mechanical properties and (iii) the electrochemical degradation behaviour of AISI 316 stainless steel/alumina brazed joints. Filler metals on such as Ag–26.5Cu–3Ti and Ag–34.5Cu–1.5Ti were used to produce the joints. Three different brazing temperatures (850, 900 and 950 °C), keeping a constant holding time of 20 min, were tested. The objective was to understand the influence of the brazing temperature on the final microstructure and properties of the joints. The mechanical properties of the metal/ceramic (M/C) joints were assessed from bond strength tests carried out using a shear solicitation loading scheme. The fracture surfaces were studied both morphologically and structurally using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction analysis (XRD). The degradation behaviour of the M/C joints was assessed by means of electrochemical techniques. It was found that using a Ag–26.5Cu–3Ti brazing alloy and a brazing temperature of 850 °C, produces the best results in terms of bond strength, 234 ± 18 MPa. The mechanical properties obtained could be explained on the basis of the different compounds identified on the fracture surfaces by XRD. On the other hand, the use of the Ag–34.5Cu–1.5Ti brazing alloy and a brazing temperature of 850 °C produces the best results in terms of corrosion rates (lower corrosion current density), 0.76 ± 0.21 μA cm−2. Nevertheless, the joints produced at 850 °C using a Ag–26.5Cu–3Ti brazing alloy present the best compromise between mechanical properties and degradation behaviour, 234 ± 18 MPa and 1.26 ± 0.58 μA cm−2, respectively. The role of Ti diffusion is fundamental in terms of the final value achieved for the M/C bond strength. On the contrary, the Ag and Cu distribution along the brazed interface seem to play the most relevant role in the metal/ceramic joints electrochemical performance.

The effect of metal transfer modes and shielding gas composition on the emission of ultraafine particles in MAG steel welding

The present study aims to characterize ultrafine particles emitted during gas metal arc welding of mild steel and stainless steel, using different shielding gas mixtures, and to evaluate the effect of metal transfer modes, controlled by both processing parameters and shielding gas composition, on the quantity and morphology of the ultrafine particles. It was found that the amount of emitted ultrafine particles (measured by particle number and alveolar deposited surface area) are clearly dependent from the main welding parameters, namely the current intensity and the heat input of the Welding process. The emission of airborne ultrafine particles increases with the current intensity as fume formation rate does. When comparing the shielding gas mixtures, higher emissions were observed for more oxidizing mixtures, that is, with higher CO2 content, which means that these mixtures originate higher concentrations of ultrafine particles (as measured by number of particles. by cubic centimeter of air) and higher values of alveolar deposited surface area of particles, thus resulting in a more hazardous condition regarding welders exposure.

Emission of airborne ultrafine particles during welding of steel plates

The present study is focused on the characterization of ultrafine particles emitted in welding of steel using mixtures of Ar+CO2, and intends to analyze which are the main process parameters which may have influence on the emission itself. It was found that the amount of emitted ultrafine particles (measured by particle number and alveolar deposited surface area) are clearly dependent from the distance to the welding front and also from the main welding parameters, namely the current intensity and heat input in the welding process. The emission of airborne ultrafine particles seem to increase with the current intensity as fume formation rate does. When comparing the tested gas mixtures, higher emissions are observed for more oxidant mixtures, that is, mixtures with higher CO2 content, which result in higher arc stability. The later mixtures originate higher concentrations of ultrafine particles (as measured by number of particles by cm3 of air) and higher values of alveolar deposited surface area of particles, thus resulting in a more hazardous condition regarding worker's exposure. © 2014 Sociedade Portuguesa de Materiais (SPM). Published by Elsevier España, S.L. All rights reserved.

Rapid automated method for on-site determination of sulfadiazine in fish farming: a stainless steel veterinary syringe coated with a selective membrane of PVC serving as a potentiometric detector in a flow-injection-analysis system

Sulfadiazine is an antibiotic of the sulfonamide group and is used as a veterinary drug in fish farming. Monitoring it in the tanks is fundamental to control the applied doses and avoid environmental dissemination. Pursuing this goal, we included a novel potentiometric design in a flow-injection assembly. The electrode body was a stainless steel needle veterinary syringe of 0.8-mm inner diameter. A selective membrane of PVC acted as a sensory surface. Its composition, the length of the electrode, and other flow variables were optimized. The best performance was obtained for sensors of 1.5-cm length and a membrane composition of 33% PVC, 66% onitrophenyloctyl ether, 1% ion exchanger, and a small amount of a cationic additive. It exhibited Nernstian slopes of 61.0 mV decade-1 down to 1.0×10-5 mol L-1, with a limit of detection of 3.1×10-6 mol L-1 in flowing media. All necessary pH/ionic strength adjustments were performed online by merging the sample plug with a buffer carrier of 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid, pH 4.9. The sensor exhibited the advantages of a fast response time (less than 15 s), long operational lifetime (60 days), and good selectivity for chloride, nitrite, acetate, tartrate, citrate, and ascorbate. The flow setup was successfully applied to the analysis of aquaculture waters. The analytical results were validated against those obtained with liquid chromatography–tandem mass spectrometry procedures. The sampling rate was about 84 samples per hour and recoveries ranged from 95.9 to 106.9%.

Establishing the main Guidelines for Cast Steel to Produce Truck Parts

Este trabalho foi realizado na Scania CV AB e teve como principal objectivo estabelecer uma diretriz sobre a possível utilização de aços vazados. Existe uma grande necessidade na realização deste trabalho, de forma a apoiar os engenheiros de projecto no seu processo de selecção dos materiais mais adequados, para produzir componentes mais leves e de elevado desempenho. Esta diretriz apresenta informação relacionada com propriedades mecânicas, processos de fundição, vazabilidade, tipologia de defeitos, tratamentos térmicos, soldabilidade e tratamentos superficiais dos aços vazados. Este trabalho foi limitado, na seleção de materiais para componentes do camião, a aços vazados que poderiam ser aplicados em dois componentes específicos: um componente estrutural da carroçaria sujeito a esforços de fadiga e a um colector de gases de combustão, sujeito a fluência, oxidação, fadiga por corrosão, fadiga-térmica e fadiga-mecânica. Foi realizado um benchmark focado nestes dois componentes de forma a saber que materiais são utilizados de momento por outras empresas concorrentes. Foi realizada ainda uma análise sobre possíveis materiais que possam ser aplicados em cada componente referido. Foi conduzida uma caracterização no estado bruto de fundição de um aço inoxidável vazado usado para produzir um protótipo do colector de gases. Esta caracterização consistiu numa análise microestrutural e medição de macro e microdurezas. Além da caracterização inicial, foram aplicados um conjunto de tratamentos térmicos, de forma a estudar a possibilidade de eliminar os carbonetos presentes inicialmente nas fronteiras de grão. As principais conclusões deste trabalho são que o aço vazado apresenta potencial para ser uma escolha válida em diversas aplicações, devido a um leque alargado de propriedades apresentadas tipicamente por este material. Relativamente a aplicações estruturais, o aço vazado é vantajoso comparativamente ao ferro fundido, quando são requeridos, por exemplo, soldabilidade e elevada resistência, combinada com elevada tenacidade à fractura. Para componentes sujeitos a elevadas temperaturas de serviço, o aço inoxidável vazado é vantajoso quando usado a temperaturas superiores a 750°C, apesar do seu elevado custo. O tratamento térmico composto por um recozimento de solubilização seguido de envelhecimento, elimina quase na totalidade os carbonetos presentes nas fronteiras de grão e verifica-se um aumento de dureza através de uma precipitação de carbonetos finamente dispersos na matriz, que poderão também aumentar a resistência à fluência.

Traduzir Teatro no Estado Novo: Gata em Telhado de Zinco Quente (1959), tradução de Sérgio Guimarães, do original Cat on a Hot Tin Roof (1955), de Tennessee Williams

À luz da viragem cultural dos Estudos de Tradução ocorrida nos anos 80 e tendo em conta a interdisciplinaridade abordada nos campos literário, cultural e histórico pela Manipulation School (Lefevere, Bassnett, Lambert, Hermans e Toury), na esteira de Itamar Even-Zohar com a Teoria dos Polissistemas (1979), a presente dissertação pretende analisar a tradução portuguesa da peça Cat on a Hot Tin Roof (1955), da autoria de Tennessee Williams, intitulada Gata em Telhado de Zinco Quente (1959), de Sérgio Guimarães. Este pode ser um caso representativo de como a tradução para teatro actua na cultura receptora numa perspectiva diatópica, antevendo a dimensão intercultural da tradução para o palco. É ao tradutor que cabe a tarefa de transferir a peça de um sistema linguístico e cultural para outro, conhecendo, se possível, o grau de representabilidade da mesma e o contexto cultural de chegada. Deste modo, é evidenciada a competência artístico-criativa do tradutor teatral que trabalha com o intuito de manter, fidus interpres, as intenções do autor da obra original. No período em que Cat on a Hot Tin Roof foi escrita, ensombrado pelo controlo sociopolítico do Macartismo nos E.U.A. e o contexto em que a tradução foi concretizada, sob a vigência da Ditadura de Salazar, a (auto)censura desempenha um papel fundamental ao moldar a produção literária nos dois sistemas culturais. Numa época em que, mais do que nos dias de hoje, traduzir consistia numa actividade subserviente e secundária, Vasco Morgado, detentor do monopólio de teatros em Lisboa encomendou a Sérgio Guimarães a tradução de uma peça de Tennessee Williams. Com base na teoria desenvolvida por Lawrence Venuti em The Translator’s Invisibility (1995), não é despiciente problematizar, neste estudo de caso, a invisibilidade do tradutor/mediador entre o texto e a representação, abordando simultaneamente as estratégias então necessárias para a peça ser aprovada e posta em cena.