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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.
81

Avaliação comparativa da refletância solar de tintas para telhas com o uso de \"pigmento frio\" e convencional nas cores cinza claro e escuro. / Comparative evaluation of solar reflectance of roof paints with the use of \"cool pigment\" and conventional in light gray and dark colors.

Souza, Ana Cristina Inacio de 21 November 2017 (has links)
O uso de \"pigmento frio\" é uma alternativa para minimizar os efeitos de \"ilhas de calor\" em grandes cidades como São Paulo. Este tipo de pigmento proporciona o desenvolvimento de fórmulas de tinta para aplicação em coberturas com cores escuras, próximo ao preto, apresentando refletância solar (SR) maior. Neste estudo, foi formulado um grupo de tintas na cor cinza claro e outro na cor cinza escuro. O primeiro grupo de tintas foi preparado com adição de pigmento preto convencional, o negro de fumo que possui natureza orgânica e o segundo grupo de tintas foi preparado com adição de \"pigmento frio\", que possui natureza inorgânica. A fração pigmentária de ambos os grupos de tintas foi preparada com auxílio do software \"CoolSim\". A revisão bibliográfica mostra que as tintas preparadas com pigmentos de natureza orgânica apresentam baixa refletância solar enquanto que as tintas preparadas com o uso do \"pigmento frio\" apresentam maior refletância solar. Os resultados de refletância solar de ambos os grupos de tintas confirmam os dados apresentados na revisão da bibliográfica. As fórmulas preparadas com o uso de \"pigmento frio\", mesmo tendo cor escura, resulta em produto mais adequado para a aplicação em superfície de cobertura como telha, devido sua capacidade de absorver menos calor, o que contribui na redução da temperatura do edifício, reduzindo a necessidade de uso de ar condicionado e auxiliando na redução do consumo de energia. / The use of \"cool pigment\" is one of the alternatives to minimize the effects of \"heat islands\" in big cities like São Paulo. This type of pigment provides the development of formulas for painting roofs with dark colors, near black, but showing higher solar reflectance (SR) than conventional pigments. In this study, a group of paint was formulated in light gray color and the other in dark gray color. The first group of paints was prepared with addition of conventional black pigment which is the carbon black that has organic nature. The second group of paints was prepared with addition of \"cool pigment\", which has inorganic nature. The pigment fraction of both groups of paints was obtained using the software \"CoolSim\". The literature review shows that finishes obtained with paints prepared with organic nature pigment has lower solar reflectance and finishes obtained with paints prepared with addition of \"cool pigment\", with inorganic nature, have a higher solar reflectance. The results of the study show that the solar reflectance of both groups of paint confirms the data obtained in the literature review. The paint formulas prepared with addition of \"cool pigment\", even presenting dark color, resulted in film more adequate for the application in surfaces of roofs and tiles due their capacity to absorb less heat. The use of \"cool pigment\" in formulas allow to obtain paints that can contribute to the reduction of the temperature of the building, by reduction the need to use air conditioning, resulting in lower energy consumption.
82

Contribution des matériaux de couverture à la contamination métallique des eaux de ruissellement / Contribution of roofing materials to the metal contamination of runoff

Sainte, Pauline 28 April 2009 (has links)
Ce travail de thèse a visé le développement d’un outil d’évaluation des flux métalliques annuels émis par les matériaux de couvertures à l’échelle d’un bassin versant, dans le contexte architectural et météorologique de l’Île-de-France. La méthodologie mise en place pour tendre vers ce but repose sur (1) l’évaluation des émissions annuelles de métaux par différents matériaux métalliques de couverture classiquement utilisés dans la région grâce à une approche expérimentale sur bancs d’essais, (2) l’établissement d’un cadre méthodologique pour la modélisation des flux métalliques émis à l’échelle annuelle par les toitures d’un bassin versant qui se base d’une part sur la modélisation des émissions métalliques par les matériaux à différentes échelles spatiales et temporelles (en fonction de la pluviométrie, de la géométrie du toit…) à partir des données obtenues sur les bancs d’essais, et d’autre part sur la quantification des surfaces métalliques des toitures d’un bassin versant. La première partie du travail a donc consisté à développer et à exploiter, sur deux sites différents, des bancs d’essais expérimentaux d’1/2 m², testant 12 matériaux métalliques issus de 5 familles (zinc, cuivre, plomb acier, aluminium), sous différentes mises en oeuvre (panneaux, gouttières, crochets de fixation). 13 espèces métalliques ont été quantifiées dans les eaux de ruissellement collectées ce qui a permis (1) d’acquérir une importante base de données de taux de ruissellement annuels par les différents matériaux, mettant en évidence que les taux de ruissellement annuels obtenus peuvent être assez importants, de l’ordre de plusieurs grammes par m² et par an pour les éléments constitutifs des matériaux, (2) de hiérarchiser ces matériaux en fonction de leur potentiel polluant, à travers la définition d’un indice de contamination métallique se basant sur les émissions de Cd, Cu, Ni, Pb et Zn et permettant de tenir compte des différences de toxicité des métaux. Une modélisation des émissions métalliques par les matériaux à différentes échelles de temps a été réalisée, conduisant à la conclusion que la hauteur de pluie, ainsi que la durée d’exposition sont des paramètres fondamentaux. Il est apparu que la hauteur de pluie seule est suffisante pour modéliser les émissions métalliques par les matériaux à des échelles de temps longues mais ne suffit pas à modéliser ces émissions sur quelques semaines. Un modèle plus complexe, basé sur une hypothèse d’accumulation / dissolution de produits de corrosion à la surface des matériaux donne des résultats satisfaisant à ces échelles de temps plus courtes. L’extrapolation spatiale des résultats de ruissellement obtenus sur les bancs d’essais s’est basé sur d’autres expérimentations, d’abord sur bancs d’essais conduisant à la conclusion que la longueur d’écoulement n’a pas d’influence sur la masse de métal entraînée dans le ruissellement, qui peut être calculée à partir de la hauteur de pluie, de la surface projetée et de l’inclinaison du panneau (qui s’avère négligeable quand elle est inférieure à 50°); puis à l’échelle de toits réels pour une étape de validation. Dans la seconde partie de ce travail, la quantification des surfaces de rampants à l’échelle d’un bassin versant a été effectuée grâce à un outil de classification d’image basé sur l’analyse de la radiométrie des matériaux à partir d’une photo aérienne. Les résultats obtenus sont encourageants, avec environ 75 à 80% des toits qui bien classés à l’issue de la classification. Les principales erreurs reposent sur des confusions de l’outil entre des matériaux de radiométries voisines (ardoise / zinc par exemple, qui peuvent être proches en fonction du degré d’ensoleillement)... / This thesis aimed to develop a tool for the evaluation of annual metallic flows emitted from roofing materials at the scale of a watershed in the architectural and meteorological context of Paris conurbation. The methodology used in this work is based on (1) the assessment of annual metallic emissions from different metallic materials typically used for roofing in the region considered through an experimental test bed, (2) the establishment of a methodological framework for modelling the metallic flow emitted from the roofs of catchment area, which is based both on the modelling of metal emissions from the materials at different spatial and temporal scales (depending on rainfall, geometry of the roof ...) from data obtained on the test bed, and on the quantification of metallic surface areas of roofs in the catchment area. The first part of the work has been based on the exploitation of experimental test beds of 1 / 2 m², testing 12 metallic materials from 5 families (zinc, copper, lead, steel, aluminium) in various implemented (panels, gutters, fixing brackets, exposed on two different sites. 13 metallic species were quantified in the collected runoff which allowed (1) to acquire a large database of annual runoff rates by different materials, highlighting that the annual runoff rates obtained can be fairly important, with an order of magnitude of several grams per square meter per year for the constitutive elements of materials, (2)to classify these materials according to their polluting potential, through the definition of an index of metal contamination taking into consideration the emissions of Cd, Cu, Ni, Pb and Zn and the differences in toxicity of metals. A modelling of metal emissions from the materials at different time scales has been conducted, leading to the conclusion that the rainfall quantity and the duration of exposure are fundamental parameters. It appeared that the rainfall value is sufficient to model metallic emission from materials for long time scales but not enough to model these emissions on a few weeks period. A more complex model, based on an assumption of accumulation / dissolution of corrosion products on the surface of the material gives satisfactory results for these time-scales periods. The spatial extrapolation of results obtained on the test bed scale was based on other experiments, first on test beds, leading to the conclusion that the length of flow has no influence on the mass of metal entrained in the runoff, which can be calculated from the rainfall quantity, the projected area and inclination of the panel (which is negligible when it is below 50 °), and then at the real roof scale for a validation step. In the second part of this work, quantification of surface areas of roofs at the scale of the catchment was conducted using a classification tool image analysis based on the radiometry of materials. The results are encouraging, with about 75 to 80% of roofs ranked on the basis of classification. The main errors are due to confusions between materials presenting nearby radiometry (slate / zinc, for example, which can be close depending on the amount of sunshine). Exploratory work was conducted for the consideration of singular elements - usually realized in metal -, from the use of unified technical documents. The evaluation of metal surfaces concerned has proved difficult to implement in an automatic way because of the small size of these elements, not visible on an aerial photo
83

Αξιοποίηση της Ερυθράς Ιλύος στη βιομηχανία παραδοσιακών κεραμικών / Utilisation of Red Mud in the heavy clay industry

Ποντίκης, Ιωάννης 05 November 2007 (has links)
Στην παρούσα Διατριβή παρουσιάζεται η μελέτη της δυνατότητας αξιοποίησης της ερυθράς ιλύος, ΕΙ, η οποία παράγεται κατά τη διαδικασία παραγωγής της αλουμίνας με τη διεργασία Bayer, για την παραγωγή δομικών παραδοσιακών κεραμικών, κύρια τούβλων και κεραμιδιών. Μελετήθηκαν αργιλούχα μίγματα με ΕΙ για ποσοστά ΕΙ από 10%κβ έως και 100%κβ.Επιγραμματικά, για την ΕΙ, πραγματοποιήθηκε χαρακτηρισμός και μελέτη της θερμικής συμπεριφοράς της. Για τα μίγματα της ΕΙ με αργιλούχες Α' ύλες, πραγματοποιήθηκε θεωρητικός σχεδιασμός τους, ενώ μελετήθηκε η επίδραση των σταδίων ανάμιξης και λειοτρίβησης, η επίδραση της ΕΙ στην πλαστικότητα, η θερμική συμπεριφορά, οι φυσικομηχανικές ιδιότητες των τελικών κεραμικών, η επίδραση της θερμοκρασίας και ατμόσφαιρας όπτησης καθώς και η περιβαλλοντική τους συμπεριφορά. Πραγματοποιήθηκαν επιπρόσθετα πιλοτικές δοκιμές παραγωγής τούβλων και κεραμιδιών. Τα αποτελέσματα της διατριβής, οδήγησαν στην ανάπτυξη μιας βέλτιστης διεργασίας παραγωγής κεραμικών με ΕΙ, η οποία αφορά στο σχεδιασμό του μίγματος με ΕΙ και την όπτησή του σε αναγωγικές συνθήκες. / In the present thesis, Bayer's process red mud, RM, is being studied as an additive and raw material for the production of heavy clay ceramics, mainly bricks and roofing tiles. A number of clay mixtures with RM were studied, for a RM content ranging from 10wt% to 100wt%. In summary, RM was characterised and studied for its thermal behaviour whereas, for the clay mixtures with RM, their design is provided, and the effect of comminution steps, the effect of RM on plasticity, their thermal behaviour, the influence of firing temperature and atmosphere, the physicomechanical properties of the end bodies, as well as their environmental behaviour are studied. In addition, pilot plan scale experiments were performed for the production of bricks and roofing tiles. The results of this thesis, led to the development of an optimised process for the production of ceramics with RM, which emphasises on the design of the body mixture as well as on the firing in reducing conditions.
84

Estudo da formula??o de massas cer?micas provenientes da regi?o do Serid?-RN para fabrica??o de telhas

Andrade, Felipe Lira Formiga 06 March 2009 (has links)
Made available in DSpace on 2014-12-17T14:57:50Z (GMT). No. of bitstreams: 1 FelipeLFA.pdf: 4959653 bytes, checksum: 0da7f126d56ee6a849bfaf9a5d53da1d (MD5) Previous issue date: 2009-03-06 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / This work has for objective study compared the characteristics and technological properties of ceramic bodies from the region of Serid?-RN. The region under study has identified 23 cities where they were 80 ceramics industries. To define the universe of search, there was a survey of pottery that are part of APL Serid? next to the IEL. The characteristics and operating conditions of ceramics industries of the region were identified through a socio-economic questionnaire applied locally, which addressed issues such as: profiles of companies, production process etc. The analysis of information collected from 24 companies identified in seven cities shows that the vast majority of industries is small, with family structure, obsolete equipment and labo, little qualified. Most of the pottery works with low technical knowledge, poor control of the production process and product technology. The raw collected were submitted to analysis of X ray diffraction, chemical composition, termical analysis, particle size distribution and plasticity. Then were produced five formulations and made by uniaxial pressure at 25 MPa for firing in temperatures varying from 850 to 1050 ?C. The firing technological properties evaluated were: mass loss to fire, lineal shrinkage, apparent density, apparent porosity, water absorption and flexural strength (3 points). The results indicated that the raw materials from the region have significant similarities in the composition chemical and mineralogical. Furthermore, it indicates the possibility of the use of cycles of firing faster and efficient than the current, limited to some clay mass burning of certain conditions / Este trabalho teve como objetivo estudar comparativamente as caracter?sticas e propriedades tecnol?gicas de massas cer?micas para telhas da regi?o do Serid?-RN. A Regi?o em estudo possui 23 munic?pios onde foram identificadas 80 ind?strias cer?micas. Para defini??o do universo da pesquisa, fez-se um levantamento das olarias que fazem parte da APL Serid? junto ao IEL do Estado. As caracter?sticas e condi??es de funcionamento das ind?strias cer?micas da regi?o foram identificadas atrav?s de um question?rio s?cio-econ?mico aplicado in loco, que abordava aspectos como: perfil das empresas, processo produtivo etc. A an?lise das informa??es coletadas em 23 empresas identificadas em sete munic?pios permite concluir que a grande maioria das ind?strias ? de pequeno porte, com estrutura familiar, equipamentos obsoletos e m?o-de-obra pouco qualificada. Grande parte das olarias opera com baixo conhecimento t?cnico, prec?rios controles do processo produtivo e tecnol?gico dos produtos. As mat?rias-primas coletadas foram submetidas a ensaios de difra??o de raios X, composi??o qu?mica, an?lise t?rmica, distribui??o de tamanho de part?culas e plasticidade. Em seguida foram produzidas cinco formula??es e confeccionados corpos-de-prova por prensagem uniaxial a 25 MPa para queima variando de 850 ?C a 1050?C. As propriedades tecnol?gicas de queima avaliadas foram: perda de massa ao fogo, retra??o linear, massa espec?fica aparente, porosidade aparente, absor??o de ?gua e carga de ruptura ? flex?o (3 pontos). Os resultados indicaram que as mat?rias-primas provenientes da regi?o apresentam significativas semelhan?as quanto ? composi??o qu?mica e mineral?gica. Al?m disso, indica-se a possibilidade da utiliza??o de ciclos de queima mais r?pidos e eficientes que os atuais, limitando algumas massas argilosas para certas condi??es de queima
85

Estudo numerico-experimental de treliças tubulares planas para coberturas padronizadas para grandes vãos. / Experimental and numerical study of hollow plane trusses for standardized roofs

Samarra, Fabio Aurelio 12 July 2007 (has links)
Orientadores: João Alberto Venegas Requena, Newton de Oliveira Pinto Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-10T14:00:01Z (GMT). No. of bitstreams: 1 Samarra_FabioAurelio_M.pdf: 11582111 bytes, checksum: 1ae70c924a9b1c83b6660980e776a855 (MD5) Previous issue date: 2007 / Resumo: O desenvolvimento de sistemas de cobertura pré-fabricados para grandes vãos, que tenham como características menor tempo de projeto, fabricação e montagem, aliado ao custo competitivo e fator estético, é tema de constantes estudos. O objetivo deste trabalho é desenvolver um sistema de cobertura metálica padronizado e modular utilizando perfis tubulares laminados sem costura. Este sistema se destina principalmente para coberturas de supermercados, shoppings, centros de distribuição, grandes lojas e indústrias, que necessitam de grandes áreas livres. Foi feita, inicialmente neste trabalho, uma descrição de todas as etapas envolvidas em um projeto, destacando, em cada uma, as vantagens e desvantagens da aplicação do perfil tubular. Através de estudos sobre os diversos sistemas de cobertura existentes, tanto no Brasil como no exterior, foi desenvolvido um sistema padronizado de cobertura para atender grandes vãos com utilização de perfis tubulares de seção circular. Para se avaliar o comportamento estrutural deste sistema, foi construído, de maneira inédita no Brasil, um protótipo de 900 m², para testar o sistema construtivo idealizado e realizar ensaios com os carregamentos reais neste tipo de estrutura. Foram realizadas análises experimentais e numéricas, que permitiram comparar o modelo real com o modelo computacional. Através dos modelos numéricos gerados, levando em conta a rigidez das ligações, foi possível identificar qual modelo computacional mais se aproxima com o real. Avaliando-se então o comportamento global da estrutura, com base em todos os resultados numéricos e experimentais obtidos, confirmou-se o comportamento previsto no cálculo computacional com o protótipo ensaiado / Abstract: This strucuture is applied mainly for supermarkets, large stores and industries. Initially, all stages involved on design of steel structure were discussed, especially the advantages and disadvantages of tubular structures. Through the study of existing roof systems, a new system using tubular steel sections was developed. To evaluate the structural behavior of this system a 900m2 prototype was built, an unprecedented occurrence in Brazil, to accomplish experimental tests with usual loads on this kind of structure. Experimental and numerical analyses were done, that allowed to compare the prototype with the numerical results. Evaluating the behavior of the entire structure, with all the results obtained on experimental tests and numerical analysis, it was concluded that the prototype is in accordance with the model / Mestrado / Estruturas / Doutor em Engenharia Civil
86

Avaliação comparativa da refletância solar de tintas para telhas com o uso de \"pigmento frio\" e convencional nas cores cinza claro e escuro. / Comparative evaluation of solar reflectance of roof paints with the use of \"cool pigment\" and conventional in light gray and dark colors.

Ana Cristina Inacio de Souza 21 November 2017 (has links)
O uso de \"pigmento frio\" é uma alternativa para minimizar os efeitos de \"ilhas de calor\" em grandes cidades como São Paulo. Este tipo de pigmento proporciona o desenvolvimento de fórmulas de tinta para aplicação em coberturas com cores escuras, próximo ao preto, apresentando refletância solar (SR) maior. Neste estudo, foi formulado um grupo de tintas na cor cinza claro e outro na cor cinza escuro. O primeiro grupo de tintas foi preparado com adição de pigmento preto convencional, o negro de fumo que possui natureza orgânica e o segundo grupo de tintas foi preparado com adição de \"pigmento frio\", que possui natureza inorgânica. A fração pigmentária de ambos os grupos de tintas foi preparada com auxílio do software \"CoolSim\". A revisão bibliográfica mostra que as tintas preparadas com pigmentos de natureza orgânica apresentam baixa refletância solar enquanto que as tintas preparadas com o uso do \"pigmento frio\" apresentam maior refletância solar. Os resultados de refletância solar de ambos os grupos de tintas confirmam os dados apresentados na revisão da bibliográfica. As fórmulas preparadas com o uso de \"pigmento frio\", mesmo tendo cor escura, resulta em produto mais adequado para a aplicação em superfície de cobertura como telha, devido sua capacidade de absorver menos calor, o que contribui na redução da temperatura do edifício, reduzindo a necessidade de uso de ar condicionado e auxiliando na redução do consumo de energia. / The use of \"cool pigment\" is one of the alternatives to minimize the effects of \"heat islands\" in big cities like São Paulo. This type of pigment provides the development of formulas for painting roofs with dark colors, near black, but showing higher solar reflectance (SR) than conventional pigments. In this study, a group of paint was formulated in light gray color and the other in dark gray color. The first group of paints was prepared with addition of conventional black pigment which is the carbon black that has organic nature. The second group of paints was prepared with addition of \"cool pigment\", which has inorganic nature. The pigment fraction of both groups of paints was obtained using the software \"CoolSim\". The literature review shows that finishes obtained with paints prepared with organic nature pigment has lower solar reflectance and finishes obtained with paints prepared with addition of \"cool pigment\", with inorganic nature, have a higher solar reflectance. The results of the study show that the solar reflectance of both groups of paint confirms the data obtained in the literature review. The paint formulas prepared with addition of \"cool pigment\", even presenting dark color, resulted in film more adequate for the application in surfaces of roofs and tiles due their capacity to absorb less heat. The use of \"cool pigment\" in formulas allow to obtain paints that can contribute to the reduction of the temperature of the building, by reduction the need to use air conditioning, resulting in lower energy consumption.
87

Conception pluridisciplinaire d’une méthode générale d’évaluation des flux de contaminants issus des ruissellements des matériaux de toitures à l’échelle urbaine : développement et illustration à partir du cas du zinc à Créteil / Multidisciplinary design of a general method for modelling roofing materials emissions on the city scale : development and illustration for zinc in the city of Créteil

Sellami, Emna 25 June 2014 (has links)
Ce travail de thèse vise à développer une méthode générale d'évaluation des flux de contaminants issus des ruissellements des matériaux de toiture à l'échelle urbaine. Cette méthode est fondée sur une démarche originale de changement d'échelles intégrant différents outils relevant des sciences de l'ingénieur et des sciences sociales. Le travail comprend la création d'une base de données bibliographique qui permet de disposer d'une vision synoptique des matériaux de toiture nouveaux et anciens utilisés à l'échelle urbaine, ainsi que des contaminants associés. La démarche de changement d'échelle – du toit à l'échelle urbaine – repose sur la notion de situation-type d'émission d'un contaminant par un matériau de toiture à laquelle est associé un flux unitaire unique. Cette notion propose une nouvelle définition de l'émission à l'échelle du toit incluant uniquement les paramètres pertinents à l'échelle urbaine. Afin de faciliter le calcul du flux à l'échelle urbaine, différents principes méthodologiques sont adoptés pour exploiter des bases de données urbaines existantes (base des modes d'occupation du sol, cadastre, images aériennes) et les adapter ou les interpréter au prisme de la problématique particulière des émissions de toitures. Ainsi, les principes de découpage et de croisement sont utilisés pour diviser l'échelle urbaine en entités homogènes. Une entité consiste en un regroupement de bâtiments, caractérisée par une répartition propre de matériaux de toitures. Ces entités sont obtenues en croisant une étude typologique des bâtiments (élaborée à partir de la base des modes d'occupation du sol) avec l'histoire urbaine et avec l'histoire des matériaux de toiture. La définition d'un ensemble de règles empiriques est nécessaire pour permettre la quantification des matériaux des différents éléments de toitures à l'échelle de la ville. Ces règles sont élaborées à partir d'une enquête et d'entretiens menés auprès d'experts des matériaux de toitures (fabricants, syndicats…) ainsi que d'une étude historique et d'une étude du marché des matériaux de toiture.Le développement intégral de la méthode jusqu'au calcul final rend indispensable le choix d'un terrain d'étude et d'un contaminant afin d'en illustrer en détail toutes les étapes de calcul. La ville de Créteil a été choisie car elle présente une mixité urbaine et historique suffisante pour embrasser la plupart des situations urbaines susceptibles d'être rencontrées en France. Elle offre également l'avantage de disposer d'un maximum de situations-types d'émissions renseignées pour le contaminant zinc qui a donc été retenu. Complétant les règles empiriques générales, une méthode statistique est développée sur ce cas d'étude. Croisée à une interprétation visuelle des matériaux de toiture à partir des images aériennes, elle permet d'évaluer la distribution des matériaux de toiture à partir d'un échantillonnage aléatoire simple de bâtiments appliqué à chaque entité homogène de la ville. Le couplage de cette distribution avec les situations-types concernées permet alors une estimation du flux de zinc émis par l'ensemble des toitures de Créteil, à savoir 813 kg.an-1 avec une incertitude de 16,6%.La méthode élaborée est généralisable à d'autres villes et d'autres contaminants. Dans cette optique, la démarche opérationnelle à suivre a été formulée de manière synthétique en fin de travail. Son utilisation peut permettre, d'une part d'évaluer à coût réduit l'impact des toitures d'une métropole ou d'une zone urbanisée sur l'environnement et, d'autre part, d'orienter les pratiques de gestion et l'utilisation des eaux de ruissellement en limitant l'apport de contaminants par les matériaux de toitures. Afin de pouvoir appliquer cette méthode à tout contaminant, des pistes ont été dressées pour définir une approche optimisant l'acquisition de données de flux annuels unitaires pour les différentes situations-types / This thesis aims to develop a general method for modelling roofing materials emissions on the city scale. This method is based on an original scaling approach integrating different tools within the engineering sciences and social sciences. The work includes the creation of a bibliographic database describing new and old roofing materials and their associated contaminants.The scaling approach - from roof to the city scale – is based on a new concept called typical-situation of contaminant emission from roofing material on the roof. For each typical situation a contaminant annual runoff rate is associated. This concept allows the transition between the roof scale and the city scale. To facilitate contaminant flow calculation on the city scale, different methodological principles are adopted to exploit and adapt existing urban databases (land use database, numerical cadastre, and aerial images) with respect to the specific issue of roofing material emissions. Thus, dividing and crossing principles are used to divide the city into homogeneous units. A unit is a cluster of buildings characterized by a specific roofing materials distribution. These units are obtained by crossing a typological buildings study (developed from the land use database) with the city urban history and the roofing material historical evolution. Defining empirical rules is necessary to quantify the distribution of the material in the different roofing elements on the city scale. These rules are developed from a survey made by conducting interviews with experts of the roofing material sector (industrials, masters of work, architects...) as well as a historical study and a market study for roofing materials.The full development of the method makes it essential to choose a study site and a contaminant in order to illustrate in detail all the calculation steps. Créteil city was selected because it presents a big diversity and a large number of buildings in order to represent most of the urban functions of any city in France. In the city of Créteil, zinc annual runoff rates have been produced for different metallic materials for the maximum of zinc typical-situation. A statistical approach was developed to complete empirical rules to compute roofing materials area distribution on the city scale. This approach is based on a stratified random sampling technique in conjunction with aerial images interpretation of the different roofing material element applied for each unit. Given the roofing material distribution and the zinc typical-situations, annual zinc flow from roofing material at Créteil city was estimated namely 813 kg.an-1 with an uncertainty of 16.6%.The developed method can be applied to other cities and other contaminants. In this context, the operational procedure of the application of this method was described at the end of this work. Our method can be used as a decision-making tool by urban planners at three levels to implement policies in order to reduce roofing pollutants emissions. In order to apply this method to any contaminant, different tracks were drawn to define an optimized approach to produce of runoff rates for different typical situations
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Estudo comparativo entre terças de aço, convencionais em vigas, em treliças planas e em treliças multiplanares / Comparative study of steel purlins in conventional beams, in planar trusses and multi-planar trusses

Vieira, Rodrigo Cuberos, 1983- 14 August 2018 (has links)
Orientador: João Alberto Venegas Requena / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-14T15:27:42Z (GMT). No. of bitstreams: 1 Vieira_RodrigoCuberos_M.pdf: 3840052 bytes, checksum: b4860daa77b57af17db9c3c0885bb512 (MD5) Previous issue date: 2009 / Resumo: As coberturas metálicas são muito utilizadas em edificações que necessitam de grandes espaços internos livres e possuem um prazo de execução pequeno, como por exemplo, galpões comerciais, industriais e centros de armazenamento e distribuição. Dentre as suas partes constituintes, as terças são responsáveis por uma parcela considerável do peso total da cobertura. Neste trabalho foi desenvolvido um amplo estudo sobre os diversos tipos de terças metálicas utilizadas em estruturas metálicas de médio e grande porte, com vãos de até 40 metros, abordando as terças em perfil laminado e formado a frio, e as terças treliçadas em perfis abertos e tubulares. Foram realizados estudos aprofundados sobre o dimensionamento de terças em perfil laminado e formado a frio, com o desenvolvimento de um programa de verificação e dimensionamento para esses tipos de terças. Também foram realizados estudos sobre o dimensionamento de terças treliçadas planas, também conhecidas como joists, que já têm a sua utilização bastante difundida, e de terças treliçadas tubulares multiplanares, cuja utilização ainda é pequena se comparada com os demais tipos de terças. Com esses estudos, foram feitas análises comparativas para diversos vãos, com as ações comumente utilizadas em estruturas que possuem coberturas metálicas, possibilitando identificar qual o tipo de terça mais adequado para cada situação estudada. Uma análise dos custos das terças também foi realizada, permitindo verificar a viabilidade da utilização das terças treliçadas tubulares em coberturas metálicas, principalmente das terças treliçadas tubulares multiplanares, cuja aplicação ainda é pequena. / Abstract: Steel roof systems are widely used in buildings that require large free internal spaces and small execution times, such as commercial and industrial warehouses and storage and distribution centers. The purlins have a considerable contribution in the roof system total weight composition. In this work was developed a study on the different types of purlins for medium and large spans, up to 40 meters, analyzing the hot-rolled sections, cold-formed sections and trusses with open or hollow sections. Purlin design studies were conducted for hot-rolled and cold-formed sections, with a computational software development for these purlin types. The use of planar trusses as purlins, also called steel joists, is already well known, and its design was studied too, as well as the multi-planar tubular trusses, whose use is still small when compared with the other purlin types. With these studies, a comparative analysis was made for various spans, applying the loads commonly used in steel roof systems, allowing the investigation of the best purlin type for each proposed situation. An analysis of the purlin costs was also performed, allowing to study the feasibility of the tubular trusses use in steel roof systems, especially the multi-planar tubular trusses, whose application is still small. / Mestrado / Estruturas / Mestre em Engenharia Civil
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Požární stanice typu P3 v Hlučíně / Fire station P3 in Hlučín

Komárková, Jana January 2018 (has links)
The subject of the diploma thesis is a new building of the P3 fire station in Hlučín. The facility will be used to perform the fire protection service of the population of the district fire brigade and municipal volunteer fire fighters. The fire station is designed as an isolated structure of rectangular shape, which is divided into three parts, and it is operationally and structurally interconnected. First part is partly underground two-storey administrative. The second part of the building is an exit garage and the third part forms of the technical background of the fire station. The object is designed as classic brick technology from Porotherm ceramic blocks on reinforced concrete base strips. The roof of part of fire and garage facilities is saddle, the roof of the technical background is flat.
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Analýza životnosti střešních PVC fólií / Analysis of the life service of PVC roofing foils

Rosecký, Pavel January 2019 (has links)
Roofing foils are known for several years as building material for roof hydro insulation but their life service is not yet fully known. This thesis is focused on problematics of life service of roofing foils. In theoretical part there is discribed structure of foils and impacts which assist degradation processes. Practical part modifies the methodology artificial aging which is simulated in QUV tester and Q-SUN XE3 tester lumber-rooms. The thesis is trying reach with the results to natural aging as close as possible. The testing captures attributes which are more prone to degradation.

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