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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.
101

Construire des charpentes autrement : le Midi rhôdanien à la fin du Moyen-Âge / Other ways to build wood frameworks : the south side of the Rhone Valley at the end of the middle age

Bouticourt, Emilien 22 October 2014 (has links)
Les édifices médiévaux du Midi rhodanien apparaissent souvent comme dépourvus de charpente ou simplement couverts de structures en bois sans grand intérêt technique. Cette idée s’appuie sur un constat indubitable : le paysage architectural de la région est essentiellement minéral. Très tôt, l’art du maçon a été favorisé par un sous-sol inépuisable en pierre à bâtir et des forêts relativement limitées dans la production de bois d’œuvre de qualité. Longtemps passés sous silence, les ouvrages charpentés existent et dénotent une singularité méconnue. L’objectif de ce travail est donc de mettre en lumière les charpentes de toit et de plancher réalisées dans ce territoire peu propice à leur réalisation. Il vise à apporter des éléments nouveaux permettant de nuancer l’idée d’une architecture sans bois. Il cherche à mettre en évidence une autre manière de concevoir les charpentes, sans doute moins monumentales que celles des régions riches en forêts mais tout aussi innovantes. La démonstration s’appuie sur des vestiges appartenant principalement aux XIVe et XVe siècles, dont la réalisation indique l’existence d’un secteur du bâtiment particulièrement actif et révélant des savoir-faire particuliers. Les charpentiers ont ainsi su pallier certaines difficultés d’approvisionnement en mettant en œuvre des formes et des techniques originales. / Most of the medievial buildings on the south side of the Rhone Valley turn out to be without roof frameworks or simply covered by wooden structures showing little technical interest. This idea is supported by an unmistakable observation: the architectural landscape of the region is mostly mineral. From early times, masonry work developed thanks to an unlimited building-stone reserve in the subsoil, and furthermore forests produced little high-quality lumber. Even though they have long been ignored, timber roof structures exist and (they) bring out remarkable singularities. The purpose of this study is to bring to light roof frameworks and floor frameworks which were built in an area little suited to their construction. It aims to bring new evidence that allows to moderate the notion of a wooden- free architecture. The study seeks to point out another way of designing of roof frames, undoubtedly less monumental than the ones built in areas with extensive forests, and yet equally innovative. The theory is based on remains dating back from the 14th to 15th centuries, the study of which proves the existence of a particularly active building sector, and reveals specific skills. Carpenters thus managed to overcome wood supply difficulties by implementing original shapes and techniques.
102

Avaliação de aspectos e impactos ambientais ao longo do ciclo de vida de telhas de fibrocimento com e sem amianto

Marques, Vinícius Martins 20 February 2014 (has links)
Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2015-06-22T13:58:54Z No. of bitstreams: 1 Vinícius Martins Marques.pdf: 1733853 bytes, checksum: bb01aad5177e6a806c2cd05405f859e3 (MD5) / Made available in DSpace on 2015-06-22T13:58:54Z (GMT). No. of bitstreams: 1 Vinícius Martins Marques.pdf: 1733853 bytes, checksum: bb01aad5177e6a806c2cd05405f859e3 (MD5) Previous issue date: 2014-02-20 / FAPERGS - Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul / Sinduscon-NH - Sindicato das Indústrias da Construção Civil, de Olarias, Ladrilhos Hidráulicos, Produtos de Cimento, Serrarias e Marcenarias de Novo Hamburgo / A indústria da construção civil tem passado por transformações significativas no Brasil e há de se destacar a crescente demanda na reutilização dos resíduos do setor, incentivada principalmente pela regulamentação da resolução n° 307/2002 do Conselho Nacional do Meio Ambiente e da lei federal n° 12.305/2010 que institui a Política Nacional de Resíduos Sólidos. Em paralelo à preocupação com os resíduos de construção, verifica-se um agravante com relação aos resíduos classificados como perigosos, especificamente, para este trabalho, tratando-se do uso de materiais com amianto. Embora se tenha conhecimento sobre as consequências e os malefícios do uso deste constituinte, observa-se resistência do setor em substituir o material. É neste cenário que se insere o presente trabalho, que tem por objetivo avaliar o ciclo de vida deste tipo de resíduo através da aplicação da técnica de Análise do Ciclo de Vida (ACV) do material amianto no setor da construção civil, especificamente as telhas empregadas em coberturas. Nesta avaliação determinaram-se, para todas as etapas, as emissões atmosféricas causadoras do efeito estufa e da chuva ácida e as que possuem toxicidade humana, além do consumo de insumos (água e energia). Posteriormente foi aplicada a técnica do Levantamento de Aspectos e Impactos Ambientais (LAIA), a fim de comparar os melhores cenários criados na análise do ciclo de vida. Este levantamento agregou à avaliação da ACV os impactos de utilização de recursos naturais e os riscos à saúde devido aos fatores cancerígenos dos materiais constituintes das telhas. Foram avaliados seis cenários de ciclo de vida de telhas de fibrocimento, sendo três com amianto e três com polipropileno (fibra alternativa). Em todos estes cenários, se fixou o local de extração das matérias-primas, o local da obra em que seriam utilizadas as telhas e o local de destinação final dos resíduos após o ciclo de vida, variando-se o local de fabricação das mesmas. Como resultado final, perante as técnicas de ACV e LAIA, o melhor cenário com polipropileno apresentou melhor avaliação em quatro das sete categorias estudadas, em comparação ao melhor cenário com amianto, que obteve índices melhores nas outras três categorias. Por outro lado, quando foram desconsideradas as etapas de transporte na avaliação, o melhor cenário com amianto gerou menos impactos em seis das sete categorias, quando comparado com o melhor cenário com as fibras de polipropileno. Deste modo, na ciência de que a etapa de transporte sempre estará presente nos ciclos de vida, considerandose as duas técnicas, e sob o foco ambiental, verifica-se que os cenários de fabricação de telhas de fibrocimento sem amianto mostraram uma menor geração de emissões, porém com maior utilização de insumos (água e energia). Cabe salientar que, de todo ciclo de vida, os resultados mostraram uma maior geração de emissões nas etapas de transporte, portanto, ao se adotar valores de transportes menores, poderiam-se encontrar cenários mais favoráveis. / The construction industry has passed through significant changes in Brazil and it is of big importance to emphasize the growing demand for the reuse of this sector’s wastes, which is encouraged mainly by the National Environment Council’s regulation of the resolution 307/2002 and by the federal law 12.305/2010, which establishes the National Policy of Solid Waste. Together with the concern about construction waste, there are additional challenges regarding waste classified as hazardous, specifically, in this research project, the use of wastes composed by asbestos. Although the consequences and disadvantages of asbestos’ use are known, there is considerable resistance of the sector in substituting its use. This research project is, then, inserted in this scenario, with the purpose of evaluating the life cycle of this type of waste by applying the technique of Life Cycle Assessment (LCA) of asbestos in the civil construction sector, specifically in roof sheets. In this evaluation, the atmospheric emissions that cause the greenhouse effect and acid rain and the emissions with human toxicity potential beyond resource consumption (water and energy) were determined, in all the stages of the life cycle. After, aiming to compare the best scenarios generated in the life cycle analysis, the Assessment of Aspects and Environmental Impacts (AAEI) technique was applied. This assessment of the LCA evaluation added the impact on the use of natural resources and the health risk due the carcinogen factors of the tiles’ constituent material. Six scenarios of the fiber-cement tiles’ life cycle were evaluated, three of them containing asbestos and the other three containing polypropylene (alternative fiber). For all of them, the raw material extraction location, the location of the construction site in which the roof sheets would be used and the destination of the waste after its life cycle were determined, varying the location of production. As a final result, regarding the LCA and AAEI techniques, the best scenario with polypropilene had a better evaluation in four of the seven categories analyzed, in comparison to the best scenario with asbestos, which had better rates in the other three categories. When the transportation stages were not considered in the evaluation, the best scenario with asbestos generated fewer impacts in six of the seven categories than the one with polypropylene fiber (alternative fiber). Thus, with the knowledge that the transportation stages always will be part of life cycles, with both techniques considered, under the light of environmental evaluation, it is noticed that production scenarios of roofing tiles without asbestos show smaller generation of emissions, although with a higher resource consumption (water and energy). It is important to mention that, regarding the entire life cycle, the results have shown higher emission generation in the transportation stages; therefore, in adopting smaller transportation values, it would be possible to find more favorable scenarios.
103

Aktivacija procesa sinterovanja kod silikatnih sistema promenom atmosfere pečenja / Activation of the sintering processes in silicate systems by changing the firing atmosphere

Rekecki Robert 27 January 2015 (has links)
<p>Proces pečenja u proizvodnji keramičkog crepa u većini slučajeva se izvodi u<br />oksidavionoj atmosferi. Dobijena mikrostruktura koja obezbeđuje najvažnije osobine<br />primene zavisi od mineralo&scaron;kog sastava polaznog materijala i temperature termičkog<br />tretmana.<br />Sa stanovi&scaron;ta proizvodnje glinenog crepa, sirovina sa značajnim sadržajem karbonata kao &scaron;to je kop gline u Kanjiži, predstavlja problem te se ne može koristiti u njenom prirodnom sastavu. U oksidacionom termičkom tretmanu, staklasta faza koja se formira razgradnjom lakotopivih glinenih minerala ne kvasi u dovoljnoj meri zemnoalkalne okside nastale razgradnjom karbonata. Očekivane nove kristalne faze, kao &scaron;to su gelenit i anortit, koje predstavljaju osnovu dobrih tehničkih osobina crepa, ne mogu nastati u potrebnoj količini. Jedno od re&scaron;enja ovog problema je pobolj&scaron;anje interakcije između silikata i CaO/MgO promenom kvaliteta atmosfere pečenja.<br />Cilj je bio da se dobije odgovor na pitanje, da li se mogu promenom tehnolo&scaron;kih<br />parametara pečenja pobolj&scaron;ati karakteristike finalnog proizvoda dobijenog od sirovinske sme&scaron;e sa visokim masenim udelom karbonata.<br />Dati su rezultati pečenja u oksidacionoj i redukcionoj atmosferi u pogledu fizičkomehaničkih karakteristika i nastanka novih kristalnih faza. U radu su primenjene metode 57Fe M&ouml;ssbauer spektroskopije, difrakcija X zraka i dilatometrijska analiza za<br />identifikaciju promena faza tokom pečenja u oksidacionoj i redukcionoj atmosferi<br />(CO/N2 atmosfera) na temperaturama od 700-1060&deg;C. Ove promene reflektuju<br />dehidroksilaciju glinenih minerala, dekompoziciju karbonata, denzifikaciju i formiranje<br />novih kristalnih faza (plagioklasi). U cilju analize industrijskih uzoraka, pored 57Fe<br />M&ouml;ssbauer spektroskopije, primenjene su i sledeće metode: skenirajuća elektronska<br />mikroskopija (SEM) sa EDS analizom, živina porozimetrija, fotoelektronska spektroskopija (XPS) i karakterizacija apsorbcije vode, otpornosti na mraz i nosivosti.<br />Primena redukujuće atmosfere pokazala se kao opravdana, dobijen je glineni crep<br />pobolj&scaron;anih karakteristika u odnosu na standardni proizvod pečen u oksidacionoj<br />atmosferi.</p> / <p>The firing process in clay roofing tile production is normally carried out in oxidizing<br />firing atmosphere. The obtained microstructure which provides the most important<br />properties of the application depends on the mineralogical composition of the starting raw material and the firing temperature.<br />Concerning the production of roofing tiles, clay raw materials with a high content of<br />carbonates such as the Kanjiza clay material, possess an inappropriate composition. The melt phase is formed after the decomposition of clay minerals during the common firing process. This liquid phase, due to its extent wetting characteristics, is not able to wet properly the earth alkali oxides obtained after the decomposition of the carbonates. The expected new crystalline phases, like gehlenite and anorthite, which are needed for the favorable technical properties of the roofing tiles, can not be formed in the required quality and quantity. One solution to this problem is the limebonding improvement by changing the conditions of the firing atmosphere.<br />The main aim of this work is to examine the effects of firing conditions on the<br />properties of clay roofing tiles with high carbonate content. The obtained physical and<br />mechanical properties and the obtained new crystalline phases are described in detail.<br />The experiment used dilatometry, X-ray diffractometry, 57Fe M&ouml;ssbauer<br />spectroscopy to identify the changes during the firing process in oxidizing and<br />reducing atmosphere (CO/N2 atmosphere) at temperatures between 700 and 1060&deg;C.<br />Furthermore, for industrial sample analysis, scanning electronmicroscopy with EDS,<br />XPS, Hg porosimetry, water absorption procedure, frost resistance and bending<br />measurements were applied.<br />The application of reducing atmosphere was proved to be valid. The obtained<br />roofing tiles had improved properties compared to the standard production which uses<br />oxidizing firing atmosphere.</p>
104

Αξιοποίηση μεταλλευτικών, βιομηχανικών παραπροϊόντων στην παραγωγή δομικών κεραμικών υλικών

Χριστογέρου, Αγγελική 14 February 2012 (has links)
Στην παρούσα διατριβή ερευνήθηκε η αξιοποίηση μεταλλευτικών, βιομηχανικών παραπροϊόντων, των στερεών Υπολειμμάτων Βορίου (ΥΒ), που δημιουργούνται σε διάφορα στάδια κατά την παραγωγική διαδικασία προϊόντων βορίου. Τα εν λόγω παραπροϊόντα, που κατηγοριοποιούνται σε πέντε ποιότητες, SBW, DBW, SSBW, TBW και MBW, χρησιμοποιήθηκαν ως πρόσθετο Α’ υλών για την παραγωγή τούβλων και κεραμιδιών, και ως Α΄ ύλη για την παρασκευή τεχνητών ελαφροαδρανών. Πραγματοποιήθηκε φυσικοχημικός χαρακτηρισμός και θερμική ανάλυση όλων των ΥΒ. Στη συνέχεια μελετήθηκε η επίδραση προσθήκης διαφορετικών συγκεντρώσεων ΥΒ (SBW και SSBW) σε αργιλούχες Α΄ ύλες. Έγινε μια πρώτη προσέγγιση παρασκευής και ελέγχου κεραμικών δοκιμίων με τη μέθοδο της ξηρής ανάμιξης και αξονικής συμπίεσης, προκειμένου να περιοριστεί το φαινόμενο διάχυσης υδατοδιαλυτών ενώσεων βορίου που περιέχονται στα ΥΒ. Η προσθήκη 5%κβ SSBW και θερμοκρασία όπτησης 900-950°C οδήγησε σε κεραμικά με παραπλήσιες ή ακόμα και βελτιωμένες ιδιότητες (αυξημένες μηχανικές αντοχές) συγκριτικά με τα κεραμικά αναφοράς. Επιπλέον εξετάστηκε η παραγωγή δειγμάτων με ΥΒ (SBW) και διάλυμα εμπορίου με βορικό (Evansite®) ακολουθώντας διαδικασία παραπλήσια της βιομηχανικής πρακτικής. Στους 1000°C, παρατηρήθηκε μείωση της απορρόφησης νερού και αύξηση της αντοχής σε κάμψη για τα δείγματα με βορικά, σε σύγκριση με τα δείγματα αναφοράς. Η προσθήκη βορικών ευνόησε τη δημιουργία νέων κρυσταλλικών κατά την όπτηση. Δεδομένης της χημικής και ορυκτολογικής σύνθεσης των ΥΒ (πλούσια σε συλλιπάσματα και υψηλές απώλειες πύρωσης), πραγματοποιήθηκε επιπρόσθετα μελέτη των φυσικοχημικών μηχανισμών θερμικής διάσπασής τους. Σε θερμαινόμενη τράπεζα παρατηρήθηκε η ικανότητα διόγκωσης και ανάπτυξης ρευστής φάσης των ΥΒ, καθώς και μιγμάτων αυτών με άλλα υλικά, με σκοπό την εργαστηριακή παραγωγή ελαφροαδρανών. Βάσει των αποτελεσμάτων προτάθηκε ένα μίγμα αποτελούμενο από 70%κβ ΥΒ, 20%κβ αργιλούχο μίγμα και 10%κβ χαλαζιακή άμμο, για τη μορφοποίηση ξηρών σφαιριδίων. Απότομη θέρμανσή τους στους 760°C οδήγησε σε πορώδη υαλοποιημένα αδρανή με φαινόμενη πυκνότητα <1g/cm3. Το ενεργειακό κόστος παραγωγής των συγκεκριμένων αδρανών είναι χαμηλότερο, καθώς παρατηρήθηκε μείωση στη θερμοκρασία σε σχέση με άλλα τεχνητά ελαφροαδρανή, που παρασκευάζονται στους 1100°C. Για την αντιμετώπιση της διάχυσης ενώσεων βορίου προς την επιφάνεια των ξηρών σφαιριδίων, που οδήγησε σε προβλήματα κατά την πειραματική διαδικασία και σε υποβάθμιση της ποιότητας των τελικών προϊόντων, εξετάστηκε η προσθήκη φρουκτόζης ως παρεμποδιστή στο μίγμα Α’ υλών, με στόχο την βελτιστοποίηση της διαδικασίας παραγωγής ελαφροαδρανών από ΥΒ. Προσθήκη έστω και 0.5%κβ φρουκτόζης οδήγησε σε ικανοποιητικό έλεγχο, ενώ οι φυσικές ιδιότητες των παραχθέντων αδρανών τα κατατάσσουν στην κατηγορία των ελαφροαδρανών, σύμφωνα με το πρότυπο ASTM 330-97. Τα αποτελέσματα οδήγησαν στην κατανόηση βασικών φαινομένων θερμικής διάσπασης και στην ανάπτυξη μιας βέλτιστης διεργασίας παραγωγής τεχνητών ελαφροαδρανών χρησιμοποιώντας ΥΒ ως εναλλακτικές Α’ ύλες, με προφανές ενεργειακό και περιβαλλοντικό όφελος. / In the present thesis, the valorisation of mining and industrial by-products, the solid boron-containing Wastes (ΒW), which are created at various stages during the production process of concentrated and refined boron products, were investigated. The by-products under consideration, existing in five types SBW, DBW, SSBW, TBW and MBW, were used as additives and raw materials in clay mixes for the production of heavy clay ceramics (bricks, tiles and artificial lightweight aggregates). The BW were characterised in means of chemical and mineralogical composition and studied for their thermal behaviour. In addition, clay mixes with different amounts of BW (SBW and SSBW) were studied. A first approach was made on the formation of ceramic samples by dry pressing in order to minimize the borate migration towards the surface. The physical and mechanical properties, as well as the microstructure of the final products were studied. For 5 wt% SSBW addition and firing at 900-950°C, the sintered bodies presented comparable or improved physical and mechanical properties with respect to the reference formulation. Moreover, SBW or a commercial available borate solution (Evansite®) were introduced in a clay-based mix aiming to investigate their behaviour during a processing cycle comparable with that followed in the heavy clay industry. For firing at 1000°C, water absorption was reduced and bending strength increased for the samples with borates, compared to the reference samples. The addition of borates resulted in the formation of new crystalline phases during firing at high temperatures. BW consist of important fluxing oxides as well as of gas producing minerals during firing. Tests were performed on the bloating behavior of BW and mixes of them with other materials, by means of heating microscopy, aiming at the laboratorial production of lightweight aggregates (LWA). A new mix was proposed, according to the obtained results, consisting of 70wt% BW, 20wt% clay mixture and 10wt% quartz sand, for the formation of pellets. Abrupt heating of the dry pellets at 760°C, for 5min, resulted in porous LWA with bulk density <1g/cm3. The process was less energy demanding as the temperature was reduced compared to the one of the synthetic aggregates produced, where the firing temperature is 1100°C. During drying a white layer of boron salts was formed on the surface of the green pellets, which result on firing of a glassy layer causing alterations of their surface and experimental difficulties. In order to address this problem, fructose was added in the raw mix as a migration inhibitor. Addition of even 0.5wt% fructose inhibited the salt formation and a glassy impervious layer was formed after firing. The physical properties of the final samples meet the requirements of LWA according to the standard ASTM 330-97. The results of this thesis, led to the development of an optimised process for the production of artificial LWA with BW, as an alternative raw material.
105

Estudo de composição para concreto extrudável para pré fabricados

Quevedo, Valéria Ramos Baltazar 23 July 2013 (has links)
Capes / Bem estabelecido e amplamente utilizado nas indústrias de polímeros e cerâmicas, o processo de extrusão vem sendo também explorado pela indústria de concreto. Embora a indústria de pré fabricados estruturais de concreto utilize superplastificantes, ainda não existem ensaios específicos para caracterizar o comportamento no estado fresco de concretos utilizados para extrusão. Foi observado que, mesmo em empresas de grande porte, a avaliação consiste no ensaio de abatimento em tronco de cone e na experiência intuitiva de um funcionário ao manipular o concreto com uma pá manual. No entanto o lançamento do concreto nos moldes é realizado por máquinas extrusoras que possuem maior força e constância na aplicação. Assim, a extrudabilidade do concreto é baseada no ensaio de “slump test” e na avaliação pessoal do operador, sendo confirmado num lote piloto no próprio processo industrial. Este trabalho teve como base o processo de fabricação de telhas extrudadas autoportantes. Visando simular algumas condições do processo de produção, foi realizada uma adaptação do ensaio da caixa-L, no qual foi inserido um vibrador de mangote no reservatório da caixa. O ensaio consistiu em avaliar o comportamento do concreto ao ser inserido no reservatório da caixa-L e logo após a abertura da comporta, com e sem vibração prévia do concreto no reservatório, para assim melhor definir um procedimento de ensaio. Para uma análise reológica foi proposta a realização de ensaio de squeeze-flow, realizado com argamassa e concreto da dosagem de concreto para extrusão. Foram utilizadas as mesmas configurações do ensaio utilizado para a argamassa: máquina de ensaio do tipo universal, célula de carga de 2000 N, prato superior e amostra, ambos com 10 cm de diâmetro, deformação livre, e com o diâmetro do punção igual ao diâmetro da amostra. Ensaios para adaptação da altura da amostra (5 cm) foram realizados de modo a evitar que ao invés de se deformar por cisalhamento ocorresse a compressão simples da brita. Foi realizada caracterização das matérias primas e testes de compactação, que determinaram a melhor proporção entre a areia fina natural, areia artificial e brita nas seguintes proporções: 25%: 25%: 50% e 0%: 50%: 50%, em massa. Para cada uma destas proporções, foram determinadas composições para o concreto com valores de “m” variando de 4,0, 4,5 e 5,0, que reduzem a quantidade de cimento em até 16%. Utilizou- se aditivo superplastificante de 3a geração à base de Policarboxilato. Para definir os teores de aditivo, foi realizado ensaio de slump test, referência na indústria para escolha de composição, definindo assim as 16 composições para estudo. A realização do ensaio possibilitou criar uma metodologia para verificar o comportamento do concreto sobre vibração, fornecendo informações tais como: aparência, coesão, tixotropia e o perfil do fluxo. Isso pode permitir realizar ajustes reais de trabalhabilidade do concreto com base nas características do processo de produção e perfil da peça extrudada. A análise reológica verificou que as condições de fluxo sofridas pela argamassa não são mantidas para o concreto, principalmente quanto à coesão e aderência. Outros fatores também foram observados, como a segregação, exsudação e comportamento ao longo do tempo. Os resultados mostram que ocorrem diferenças significativas, sendo que algumas características apresentadas na argamassa não se reproduzem no concreto. Ensaios de resistência mecânica à compressão mostraram que todas as composições atendem ao valor mínimo previsto em norma e quanto à trabalhabilidade observou-se que as composições somente com areia artificial apresentaram falta de coesão, perceptível no ensaio de slump test. Definiu-se o ensaio de caixa-L adaptado com vibração prévia como melhor procedimento de ensaio. Os resultados mostraram que mesmo composições com abatimento nulo, que seriam descartadas pela indústria, apresentaram trabalhabilidade e fluíram com vibração, sendo que os teores de aditivo influenciaram no perfil e no tempo do escoamento. / A well established and widely used in the industries of ceramics and polymers, the extrusion process has been also explored by the concrete industry. Although the industry of prefabricated structural concrete using superplasticizers, there are still no specific tests to characterize the behavior in the fresh concrete used for extrusion. Although the industry prefabricated concrete structural use superplasticizers, there're not no specific tests to characterize the behavior of the fresh concrete used for extrusion. It was observed that, even in large companies, the evaluation consists of the slump test in truncated cone and the intuitive experience of an employee to handle the concrete with a shovel manual. However the concrete cast in molds is done by extruding machines that have greater strength and consistency in application. Thus extrudability of concrete is based on the testing of "slump test" and the personal evaluation of the operator, being confirmed in a pilot batch in industrial process itself. This work was based on the manufacturing process of extruded tiles freestanding. Aiming to simulate some of the conditions of the production process, there was an adaptation of the test box-L, which was inserted in the reservoir hose vibrator housing. The test consisted in assessing the behavior of the concrete to be inserted into the reservoir from the L-box and immediately after opening the gate, with and without prior vibration of concrete in the tank, so as to better define a test procedure. For a rheological analysis was proposed to carry out squeeze flow test conducted with concrete mortar and concrete strength for extrusion. We used the same settings as used for the test mortar testing machine universal type, load cell 2000 N, and sample top plate, both 10 cm in diameter, free deformation, and the punch diameter equal to the diameter sample. Assays for adjusting the height of the sample (5 cm) were made in order to avoid that instead of being deformed by the compressive shear occur in the gravel. Was performed characterization of raw materials and compression testing which determined the best ratio between the fine sand natural, artificial sand and gravel in the following proportions: 25%: 25%: 50% to 0%: 50%: 50% by mass. For each of these ratios were determined for concrete compositions with values of "m" ranging from 4.0, 4.5 and 5.0, which reduces the amount of cement up to 16%. We used superplasticizer 3rd generation based Polycarboxylate. To set the content of admixture slump test was performed test, the industry benchmark for the choice of composition, thereby setting the 16 estudo.Para compositions for each of these ratios were determined for concrete compositions with values of "m" varying from 4.0, 4.5 and 5.0, which reduces the amount of cement up to 16%. We used superplasticizer 3rd generation based Polycarboxylate. The main test possible to create a methodology to assess the behavior of concrete on vibration, providing information such as: appearance, cohesion, thixotropy and flow profile. This can make adjustments allow real concrete workability based on the characteristics of the production process and extruded profile part. The rheological analysis verified that the flow conditions experienced by the cement is not retained in the concrete, especially in regard to cohesion and adhesion. Other factors were also observed, such as segregation, exudation and behavior over time. The results show that significant differences occur, and some features disclosed in the mortar on the concrete not reproduced. Testing of mechanical strength showed that all compositions meet the minimum standards set out in and about the workability was observed that the compositions only with artificial sand showed a lack of cohesion noticeable slump test. Set up the test L-box pre adapted as best vibration test procedure. The results showed that even compositions with zero rebate which would be discarded by the industry had flowed workability and vibration, and the admixture levels and influence the time profile of the flow.
106

Estudo comparativo da qualidade da água de chuva coletada em cobertura convencional e em telhado verde

Budel, Marcel Aramis 31 March 2014 (has links)
CAPES / O estudo consiste em uma comparação da qualidade da água da chuva coletada em duas formas distintas de captação: um sistema composto por um telhado inclinado com telhas de concreto, nomeada (casa 1) e o outro composto por uma cobertura plana com telhado verde, ou seja, vegetado, nomeada (casa 2). Tem por objetivo caracterizar os sistemas utilizados nas duas formas de cobertura, analisar a qualidade da água da chuva captada nos dois sistemas e fazer o acompanhamento da qualidade da água armazenada para posterior uso ao longo do estudo com o intuito de verificar a eficiência e comportamento dos sistemas de captação. Objetiva ainda encontrar relações nas variáveis envolvidas e apresentar os resultados de forma a estabelecer uma comparação qualitativa no desempenho das duas coberturas. O estudo foi realizado em duas casas localizadas na região noroeste da cidade de Curitiba, capital do Paraná. Na casa 1, com telhas de concreto, a água da chuva que escoa pelo telhado é primeiramente coletada por uma calha, seguindo por um duto vertical até o nível do solo, no qual se encontra um filtro simples, então a água é encaminhada para uma cisterna, onde é armazenada, para posterior uso na torneira externa para onde a água é bombeada. Já na casa 2, com cobertura plana vegetada, a água da chuva após passar pelo telhado verde é conduzida por dutos verticais até a cisterna de concreto no nível do solo, então uma eletrobomba recalca a água até um reservatório localizado na cobertura, acima do nível do telhado verde, para armazenamento e posterior uso na torneira externa. As amostras coletadas em nove eventos (17/05/2013 a 03/12/2013) foram analisadas quanto à: pH, turbidez, oxigênio dissolvido e temperatura, que foram medidos no próprio local. Demanda química de oxigênio (DQO), amônia, nitrito, nitrato e fosfato foram amostrados e analisados no laboratório de Saneamento da UTFPR, Campus Ecoville. Ainda quanto à presença de coliformes totais e termotolerantes (E. Coli), foram realizados em um laboratório terceirizado. Observou-se que o telhado convencional da casa 1 apresentou maior qualidade no parâmetro turbidez e demanda química de oxigênio (DQO), já o telhado verde diminuiu a acidez natural da água da chuva. As duas coberturas se mostraram eficientes pela concentração de amônia e nitrato, contudo indicaram concentrações elevadas de fosfato. Nos parâmetros microbiológicos os dois telhados não obtiveram qualidade suficiente para atender a NBR 15.527/2007. Desta forma, tomadas as devidas precauções, se recomenda o uso da água proveniente dos telhados, vegetados e convencional, para descargas de bacias sanitárias, irrigação de gramados e plantas ornamentais, lavagem de veículos, limpeza de calçadas e ruas, limpeza de pátios, espelhos d'água e usos industriais, conforme estabelecido na norma. / The study consists of a comparison of the quality of rainwater collected in two distinct ways of catchments: a system composed of a pitched roof with concrete tiles and another consisted of a vegetated flat coverage, as known as green roof. It aims to characterize the systems used in both forms of coverage, to analyze the quality of rainwater captured in the two systems and to monitor the quality of water stored for later use throughout the study in order to verify the efficiency and performance of catchment systems. It also aims to find relations in the involved variables and to present the results in order to establish a qualitative comparison in the performance of two coverages. The study was conducted in two houses located in the northwest region of the city of Curitiba, capital of Paraná. The appointee, house 1, has a pitched roof with concrete tiles, the rainwater that seeps through the roof is first collected by a trough, followed by a vertical duct to the ground level, with a simple filter, then the water is sent into a tank where it is stored for later use in the external faucet where the water is pumped. However, at house 2, with vegetated flat roof, after passing through the green roof the rainwater is driven by vertical ducts to the concrete tank at ground level, then an electric pump represses the water to a reservoir located on the roof, above the green roof ́s level for storage and later use on the external tap. Samples collected in nine events (17/05/2013 to 03/12/2013) were analyzed for pH, turbidity, dissolved oxygen and temperature, they were measured in situ. Chemical oxygen demand (COD), ammonia, nitrite, nitrate and phosphate were sampled and analyzed in the laboratory of Sanitation UTFPR Campus Ecoville. Nevertheless, for the presence of total and fecal coliforms (E. coli), tests were performed on an outsourced laboratory. As for the results obtained, the conventional roof house 1 rainwater had higher quality in turbidity and chemical oxygen demand (COD) parameter, whereas in house 2 the green roof reduced the natural acidity of rainwater. The two covers were effective in the concentration of ammonia and nitrate, though indicated high concentrations of phosphate. Microbiological parameters in neither roofs met the NBR 15.527/2007 quality. Thus, taken due precautions, it is recommend the use of water from roofs, vegetated and conventional, to flush toilets, to irrigate lawns and ornamental plants, to wash vehicles, to clean sidewalks and streets, to clean patios, water mirrors and to industrial uses, as defined in the standards.
107

Estudo comparativo da qualidade da água de chuva coletada em cobertura convencional e em telhado verde

Budel, Marcel Aramis 31 March 2014 (has links)
CAPES / O estudo consiste em uma comparação da qualidade da água da chuva coletada em duas formas distintas de captação: um sistema composto por um telhado inclinado com telhas de concreto, nomeada (casa 1) e o outro composto por uma cobertura plana com telhado verde, ou seja, vegetado, nomeada (casa 2). Tem por objetivo caracterizar os sistemas utilizados nas duas formas de cobertura, analisar a qualidade da água da chuva captada nos dois sistemas e fazer o acompanhamento da qualidade da água armazenada para posterior uso ao longo do estudo com o intuito de verificar a eficiência e comportamento dos sistemas de captação. Objetiva ainda encontrar relações nas variáveis envolvidas e apresentar os resultados de forma a estabelecer uma comparação qualitativa no desempenho das duas coberturas. O estudo foi realizado em duas casas localizadas na região noroeste da cidade de Curitiba, capital do Paraná. Na casa 1, com telhas de concreto, a água da chuva que escoa pelo telhado é primeiramente coletada por uma calha, seguindo por um duto vertical até o nível do solo, no qual se encontra um filtro simples, então a água é encaminhada para uma cisterna, onde é armazenada, para posterior uso na torneira externa para onde a água é bombeada. Já na casa 2, com cobertura plana vegetada, a água da chuva após passar pelo telhado verde é conduzida por dutos verticais até a cisterna de concreto no nível do solo, então uma eletrobomba recalca a água até um reservatório localizado na cobertura, acima do nível do telhado verde, para armazenamento e posterior uso na torneira externa. As amostras coletadas em nove eventos (17/05/2013 a 03/12/2013) foram analisadas quanto à: pH, turbidez, oxigênio dissolvido e temperatura, que foram medidos no próprio local. Demanda química de oxigênio (DQO), amônia, nitrito, nitrato e fosfato foram amostrados e analisados no laboratório de Saneamento da UTFPR, Campus Ecoville. Ainda quanto à presença de coliformes totais e termotolerantes (E. Coli), foram realizados em um laboratório terceirizado. Observou-se que o telhado convencional da casa 1 apresentou maior qualidade no parâmetro turbidez e demanda química de oxigênio (DQO), já o telhado verde diminuiu a acidez natural da água da chuva. As duas coberturas se mostraram eficientes pela concentração de amônia e nitrato, contudo indicaram concentrações elevadas de fosfato. Nos parâmetros microbiológicos os dois telhados não obtiveram qualidade suficiente para atender a NBR 15.527/2007. Desta forma, tomadas as devidas precauções, se recomenda o uso da água proveniente dos telhados, vegetados e convencional, para descargas de bacias sanitárias, irrigação de gramados e plantas ornamentais, lavagem de veículos, limpeza de calçadas e ruas, limpeza de pátios, espelhos d'água e usos industriais, conforme estabelecido na norma. / The study consists of a comparison of the quality of rainwater collected in two distinct ways of catchments: a system composed of a pitched roof with concrete tiles and another consisted of a vegetated flat coverage, as known as green roof. It aims to characterize the systems used in both forms of coverage, to analyze the quality of rainwater captured in the two systems and to monitor the quality of water stored for later use throughout the study in order to verify the efficiency and performance of catchment systems. It also aims to find relations in the involved variables and to present the results in order to establish a qualitative comparison in the performance of two coverages. The study was conducted in two houses located in the northwest region of the city of Curitiba, capital of Paraná. The appointee, house 1, has a pitched roof with concrete tiles, the rainwater that seeps through the roof is first collected by a trough, followed by a vertical duct to the ground level, with a simple filter, then the water is sent into a tank where it is stored for later use in the external faucet where the water is pumped. However, at house 2, with vegetated flat roof, after passing through the green roof the rainwater is driven by vertical ducts to the concrete tank at ground level, then an electric pump represses the water to a reservoir located on the roof, above the green roof ́s level for storage and later use on the external tap. Samples collected in nine events (17/05/2013 to 03/12/2013) were analyzed for pH, turbidity, dissolved oxygen and temperature, they were measured in situ. Chemical oxygen demand (COD), ammonia, nitrite, nitrate and phosphate were sampled and analyzed in the laboratory of Sanitation UTFPR Campus Ecoville. Nevertheless, for the presence of total and fecal coliforms (E. coli), tests were performed on an outsourced laboratory. As for the results obtained, the conventional roof house 1 rainwater had higher quality in turbidity and chemical oxygen demand (COD) parameter, whereas in house 2 the green roof reduced the natural acidity of rainwater. The two covers were effective in the concentration of ammonia and nitrate, though indicated high concentrations of phosphate. Microbiological parameters in neither roofs met the NBR 15.527/2007 quality. Thus, taken due precautions, it is recommend the use of water from roofs, vegetated and conventional, to flush toilets, to irrigate lawns and ornamental plants, to wash vehicles, to clean sidewalks and streets, to clean patios, water mirrors and to industrial uses, as defined in the standards.
108

Formula??o e caracteriza??o de massas de gr?s porcelanato preparadas a partir de mat?rias-primas naturais do Rio Grande do norte e com adi??o de chamote de telhas / Formulation and characterization of porcelanized stoneware tiles mixtures from regional raw materials and roofing tile chamote

Melo, Maxymme Mendes de 19 May 2006 (has links)
Made available in DSpace on 2014-12-17T14:57:51Z (GMT). No. of bitstreams: 1 MaxymmeMM.pdf: 1674410 bytes, checksum: 96bf3d5d9b4ae824e79c65b37e8b9bf7 (MD5) Previous issue date: 2006-05-19 / Traditional ceramics have an important role in the economy of Rio Grande do Norte. The local industries manufacture over 50 million shingles a month, corresponding to 60% of their overall production. As a result of processing flaws, roughly 20% of the production must be discarded, since little or no use has been envisaged for such fired components. Therefore, the use of this kind of residue, especially in the composition of other ceramic materials, comes as an interesting option from the economical and environmental point of view. In this scenario, the objective of the present study was to assess the effect of the addition of fired shingle waste in the composition of porcelainized stoneware tiles. To that end, two porcelainized stoneware tiles compositions were initially prepared. Subsequently, contents from 10 to 30% of roofing tiles chamote were added to each one of them. All raw materials and grog were characterized by FRX, XRD, and thermal analysis. The ceramics were fired using natural gas for 30 min at different temperatures, i.e. 1150, 1200 and 1250?C, and fully characterized. The addition of roofing tiles chamote resulted in composition with superior properties compared to additive-free compositions. Porcelainized stoneware tiles products that fulfill required standards for practical applications were achieved / A ind?stria de cer?mica vermelha ? um dos segmentos de maior import?ncia na economia do Rio Grande do Norte. Nesse setor, o material mais produzido ? a telha, ocupando mais de 60% de todos os artefatos produzidos, com mais de 50 milh?es de pe?as fabricadas por m?s. Sabe-se que devido ? falhas no processamento, o teor de res?duos desse material no RN, pode chegar a um valor de at? 20%, o que significa mais de 10 milh?es de telhas indo diretamente para aterros, visto que estas, depois de queimadas, n?o podem ser reutilizadas no processo de fabrica??o. Desta forma, o uso desse rejeito na produ??o de cer?micas com alto valor agregado, como ? o caso do gr?s porcelanato, se torna uma op??o vi?vel. Do ponto de vista econ?mico essa viabilidade se d?, pelo fato de utilizar-se um rejeito como parte da formula??o. Do ponto de vista ambiental, a viabilidade est? em reduzir o ac?mulo desses rejeitos nos aterros sanit?rios. Desta forma, o presente trabalho tem o objetivo de estudar a influ?ncia da adi??o de descarte de telhas em formula??es de gr?s porcelanatos. Para isso, utilizou-se duas formula??es, adicionando concentra??es de 10, 20 e 30% de chamote para cada uma delas. O Chamote e as mat?rias-primas foram caracterizadas por FRX, DRX, TG, ATD e AG. As queimas foram realizadas em forno a g?s natural com tr?s temperaturas, por 30 minutos de patamar: 1150, 1200 e 1250?C. Ap?s a sinteriza??o os corpos-de-prova foram submetidos a: ensaios f?sicos de RL, AA, PA, MEA, TRF e dilatometria; an?lise mineral?gica por DRX; e microestrutural por MEV. Obteve-se para algumas das formula??es com a adi??o de chamote, propriedades superiores ?s das exigidas por normas para o gr?s porcelanato
109

O uso do pet em telhas translúcidas visando o conforto natural lumínico e térmico / The use of pet in translucent roofing in order to a luminous, thermal and natural comfort

CAVALCANTE, Christiane Rosa de Paiva 23 September 2011 (has links)
Made available in DSpace on 2014-07-29T15:01:48Z (GMT). No. of bitstreams: 1 Dissertacao Christiane R de P Cavalcante.pdf: 2530151 bytes, checksum: c8418cc369a22584f8884d3a586e48ae (MD5) Previous issue date: 2011-09-23 / The PET, tereftalato of ethylene, is the most known and appropriated material in the manufacture of several packings of nourishing products, specially the bottles of beverages. The correct management of the urban solid residues to the transformation into those which return to the use and the environment education are essential tasks to guarantee the exploitation of the complete useful life of this material and to prevent it on environmental focus. From the industrial point of view, the PET recycling in Brazil is still a recently activity. All around the country there are recycling industries, but they were created specially for environmental reasons. Although they became an important source of jobs and income. That s why, nowadays, recycling industries are considered an important social order factor. In Brazil, there are industries which transform the PET into roofing tiles for covering for drawing or injection. In this work, the main analyzed topic was the properties of the transparent roofing tiles of PET and other materials, the polycarbonate and the available fiberglass in the civil construction market through the main properties and relative parameters to the natural illumination, including its optic properties and the objective of the luminous and thermal comfort. Using the results of the spectrophotometer device, it was made a comparison among the studied materials in order to help the best choice of luminous and thermal comfort materials. PET, compared to the other studied materials, is not the best choice, even concerned to the price. However, for environmental solutions, the best way to use this solid waste recycling is the utilization of the PET as transparent roofing tiles, specially considering the amount of material all around rivers, scoots, attires, and so on. / O PET, tereftalato de etileno, é o material mais conhecido e apropriado na fabricação de várias embalagens de produtos alimentícios, entre as quais se destacam as garrafas de refrigerante. A correta gestão dos resíduos sólidos urbanos, com a transformação desses resíduos para o retorno ao uso, e a educação ambiental são tarefas essenciais para garantir o aproveitamento da totalidade da vida útil daquele material e evitar que seja ele o foco de contaminação ambiental. Do ponto de vista industrial, a reciclagem de PET no Brasil ainda é uma atividade recente. Há indústrias recicladoras em todo o território nacional criadas primordialmente para guarnecer uma questão ambiental, mas que culminou em uma questão de ordem social com geração de empregos e renda. No mercado existem no Brasil empresas que transformam o PET em telhas de cobertura por extrusão ou injeção. Neste trabalho foram analisadas as propriedades das telhas transparentes de PET e de outros materiais, o policarbonato e a fibra de vidro disponíveis no mercado da construção civil através das principais propriedades e parâmetros relativos à iluminação natural, incluindo suas propriedades óticas e com o objetivo do conforto lumínico e o térmico. Por meio dos resultados obtidos pelo uso do aparelho de espectrofotômetro, elaborou-se uma comparação entre os materiais estudados a fim de auxiliar na sua escolha, visando um melhor conforto lumínico e térmico. O PET não obteve o comportamento ansiado em comparação com os demais materiais estudados, também em relação ao custo pode-se observar que é mais onerosa a instalação do telhado de PET. Mas já em relação ao quesito de reaproveitamento de resíduos sólidos urbanos descartados no meio ambiente, o PET possui melhor desempenho uma vez que seu material se encontra em abundância e pode ser transformado e reaproveitado, amenizando o impacto ambiental.
110

Železniční stanice ve Zlíně / Railway Station in Zlin

Benýšek, David January 2018 (has links)
The diploma thesis deals with design assessment railway station steel structure with roofing platform in Zlín. The structure has a lenght 80m, a width 44m and a height 9,87m. The structure is divided into two parts, first part consists office building and second part consistsroofing platform.The supporting structure of the hall is a transverse bond, which is formed by rounded truss ginder and truss columns with axial distance of 5 meters. The main construction material is steel S355JR. The work contains structural design report load-bearing elements, including joints and details. The calculations are processed according to the valid norms ČSN EN.

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