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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.
41

Náhrada křemičitého plniva v opravných maltách umělým hutným materiálem / Substitution of silica filler in the correction mortars by artifical compact material

Jankovský, Július January 2009 (has links)
Master‘s thesis “Substitution of silica filler in the repair mortars by artifical compact material“ could by generally divided into two parts theoretical and experimental. The theoretical part is mainly focused on summarizing knowledge about repair mortars. The repair mortars are used for reprofilation of disrupted concrete layers, and therefore some of the most common defects of these layers, from which we can determine requirements for repair mortars are listed in the thesis. In the theoretical part, there is also mentioned a general formula of how to prepare a repair mortar, also there are described manufacture and characteristics of the most important ingredients of mortars such as cement, filler (aggregate), water and chemical modificators. Above all the theoretical part is focused on the effects that individual ingredients have on the resulting properties of repair mortars. The experimental part could be further divided into two parts. In the first part there are listed properties of the individual investigated materials and also there is introduced theoretical basis for particular tests of properties of repair mortars, such as analysis of grading distribution of a filler (aggragate), tests of flexular and compression strengths and frost resistance. In the first part there are also proposed formulae of mortar mixtures, where part of the original filler was substituted by an abrasive material TRYMAT, artificial compact aggregate made from blast furnace slag UHK d/D, or their combination. The properties of these mortar mixtures were compared to referential mortar mixture PANBEX R1. In the second part of experimental section is dedicated to summarization and discussion of the obtained results for individual mortar mixtures.
42

Analýza organických příměsí v historických maltových materiálech / Analysis of organic additives in historical mortars

Křížová, Iva January 2012 (has links)
- 4 - Abstrakt The aim of this diploma thesis was to determine the possibility of identifying the protein and lipid additives, such as blood, gelatine, curd, lard and eggs, in the model samples of lime based mortars using Raman spectroscopy and gas chromatography- mass spectrometry. It was proved that the method of Raman spectroscopy can determine the presence of organic additives in the order of one weight percent. The gas chromatography enables to detect lipid additives from the order of hundredths weight percent. Unambiguous resolution of protein additives can be done in the samples with the concentrations up to the order of one weight percent of the additives.
43

Étude de la valorisation des déblais de chantiers de tunnels en granulats à béton / Study of the use of tunnel excavated materials from Lyon-Turin railway link as aggregates for concrete structures

Colas, Jérémy 04 December 2012 (has links)
La société LTF (Lyon Turin Ferroviaire), filiale de RFF (Réseau Ferré de France) et de RFI (Réseau Ferré Italien) est le promoteur de la section transfrontalière de la future liaison ferroviaire entre Lyon et Turin. LTF souhaite valoriser une grande partie des 16 millions de m3 de déblais qui seront générés par les chantiers du futur tunnel de base en granulats à béton pour le revêtement du tunnel. Cette solution est proposée dans le cadre d'une démarche de développement durable. Cependant, pour une partie des matériaux qui doivent être valorisés en granulats à béton, la teneur en sulfates est comprise entre 1,61 et 4,30% en masse (exprimé en SO3). Ces matériaux se démarquent alors par rapport au contexte réglementaire qui limite la teneur en sulfates dans les granulats à béton à 0,2% pour ce type d'ouvrage. Cette prescription est appliquée pour éviter les risques de dégradation du béton par réaction des sulfates apportés par les granulats avec certains composants présents dans le ciment. Ce phénomène est connu sous le terme de réaction sulfatique interne. Les travaux de recherche ont porté dans un premier temps sur la lixiviation des sulfates issus des matériaux d'excavation. Les résultats ont montré que les sulfates sont rapidement accessibles dans les fractions granulométriques inférieures à 4 mm. Un possible traitement des matériaux par lavage avant leur utilisation dans le béton peut être une solution pour limiter l'attaque sulfatique interne. Dans un second temps, pour définir un liant adapté à ce type de granulats, une étude comparative de différents ciments supposés résistants aux sulfates a été mise en place. Trois essais accélérés ont été développés afin de prendre en compte le risque de dégradation des matériaux cimentaires par formation d'ettringite et de thaumasite. Seuls deux ciments présentent un bon comportement vis-à-vis de la réaction sulfatique interne engendrée par des granulats contenant une forte teneur en sulfates. Il s'agit d'un ciment Portland à très faibles teneur en alcalins et ne contenant quasiment pas d'aluminates tricalciques ainsi qu'un ciment sursulfaté. Enfin, une dernière solution innovante a été proposée et réside dans l'utilisation des sulfates apportés par les matériaux d'excavation pour réaliser le gypsage du ciment. Les sulfates provenant du sable excavé permettent de réguler correctement la prise du matériau cimentaire au même titre que les sulfates de calcium ajoutés au clinker dans le ciment / The construction of a 57 km length base tunnel for the future railway link between Lyon (France) and Turin (Italy) promoted by Lyon Turin Ferroviaire (LTF), subsidiary of Réseau Ferré de France (RFF) and Rete Ferroviaria Italiana (RFI), will result in the production of 16 millions of m3 of excavated materials. In order to promote efficient and sustainable management of natural resources and to reduce greenhouse gas emission and environmental impact, one wish of LTF is to use the most part of these materials as concrete aggregates. However, a part of the excavated materials from LTF tunnel has a sulphate content between 1.46 and 4.30% (expressed in mass of SO3) and cannot be used considering the European standards, which drastically limit the sulphate content in order to avoid structural damages resulting from internal sulphate attack. The sulphate content is limited to 0.2% for this type of construction. The first study, carried out in order to define solutions for the use of these excavated materials, focuses on the behaviour of sulphates, more particularly on their leaching in solution in order to determine the sulphate content that could be released in the concrete. The results show that the sulphates are quickly available for the particles size lower than 4 mm. The washing of excavated materials before their use in concrete can be a solution to limit the internal sulphate attack. The second study has been conducted in order to define a suitable cement for the use of excavated materiels as aggregates. A comparative study of different cements supposed to be resistant to sulphates has been carried out. Three accelerated tests have been developed to assess the risk of degradation of cementitious materials by formation of ettringite and thaumasite. Only two cements show a good behavior against the internal sulphate attack resulting from sulphated aggregates. These cements are a Portland cement with a very low calcium aluminates and alkaline contents and an over sulphated cement.In the frame of a third study, an innovative solution has been proposed and concerns the using of excavated materials as a source of sulphates for regulating the hydration of cement. Sulfates from the excavated sand can regulate the cement hydration and then cancel any further damage due to sulphates
44

Contribution à l’étude du patrimoine bâti. Méthodes de diagnostic des pathologies des structures et moyens de restauration : Etude de cas. Site archéologique Volubilis au Maroc / Contribution to the study of the built heritage. methods of diagnosis of pathologies of the structures and means of restoration : Case study. The archaeological site of Volubilis in Morocco

Aalil, Issam 05 December 2017 (has links)
La restauration du patrimoine bâti est une exigence pour assurer sa pérennité. Le site archéologique Volubilis au Maroc, classé patrimoine mondial de l’UNESCO depuis 1997, nécessite des travaux de restauration. L’objectif de cette thèse est de déterminer les causes de dégradation de ses pierres, et de proposer des mortiers pour la restauration de ses monuments. Dans un premier temps, une caractérisation multi-échelle a été réalisée sur les trois faciès de la calcarénite, la pierre la plus prépondérante du site. Elle a révélé que malgré la composition minéralogique similaire des trois faciès, ils présentent des propriétés hydriques, thermiques et mécaniques dissemblables et des durabilités contrastées vis-à-vis de la cristallisation de sel. Des essais non destructifs permettraient de distinguer les trois faciès en estimant leurs porosités et leurs coefficients de capillarité. Dans un second temps, une étude de diagnostic a révélé la présence l’halite et du gypse dans la majorité des pierres altérées par des détachements et des pertes de matière. Ces sels proviennent des mortiers avoisinants, utilisés pendant les interventions antérieures. De plus, l’altération des calcarénites non contaminées est vraisemblablement due à des contraintes thermiques. Dans la dernière partie, nous avons formulé des mortiers à base de chaux, du sable et de la poudre de brique à l’aide de la méthode des plans de mélanges. Cette démarche permettrait de déterminer des mortiers compatibles à la pierre calcarénite. / The restoration of the built heritage is mandatory to ensure its sustainability. The archaeological site of Volubilis in Morocco, registered on the UNESCO World Heritage list since December 1997, requires restoration works. The main objective of this thesis is to determine the causes of stones’ deterioration and to propose mortars for restoration of its monuments. Firstly, a multi-scales characterization study was carried out on the three facies of the calcarenite, the main building stone in the site. It showed that despite their similar mineralogical composition, the three facies have dissimilar hydric, thermal and mechanical properties and they are quite different in terms of durability against salt crystallization. Besides, non-destructive testing could be used to distinguish the three facies by estimating their porosities and their coefficients of capillarity. Secondly, a diagnosis study revealed the presence of halite and gypsum in most deteriorated stones affected by detachment and loss of material. These salts originated from neighboring mortars, used during the previous interventions. In addition, the deterioration of uncontaminated calcarenites is likely due to thermal stresses. In the last part, we formulated mortars using lime, sand and the brick dust using the mixtures method. This approach would determine compatible mortars to the stone calcarenite.
45

Aderência de chapiscos em concretos estruturais - melhoria da microestrutura da zona de interface pela adição da sílica da casca de arroz / Adherence of slurry mortars in structural concretes – microstructure improvement of the interfacial transition zone through addition of silica obtained from rice husk

Silva, Vanessa Silveira 09 February 2004 (has links)
Avaliação da aderência de chapiscos em substratos de concretos estruturais. Com o objetivo de aprimorar a microestrutura da zona de interface argamassa/concreto e aumentar a resistência de aderência do revestimento, utilizou-se chapisco com baixa relação água/aglomerante e adição da sílica ativa extraída da casca de arroz como tratamento da zona de interface da argamassa e substrato. Para avaliar a aderência do revestimento realizaram-se ensaios de determinação da resistência de aderência à tração. Utilizou-se a técnica de microscopia eletrônica de varredura associada à espectrografia por dispersão de energia para analisar a microestrutura da zona de interface do chapisco e concreto. Os resultados do programa experimental evidenciaram que, quando se utiliza a sílica extraída da casca de arroz no chapisco, em teores de 5% em relação à massa de cimento, há aumentos significativos de resistência de aderência do revestimento. Nos estudos microestruturais, foi possível observar que devido às ações físicas e químicas da sílica da casca de arroz, formou-se uma microestrutura densa, de baixa porosidade e com a presença de produtos hidratados pouco cristalinos na interface chapisco/concreto. A implementação de uma ponte de ligação constituída por chapiscos com sílica ativa, entre os substratos e as argamassas de revestimento, mostrou-se eficiente em superfícies muito lisas ou em materiais pouco porosos, como no caso das estruturas de concreto armado. / The present thesis evaluates the adherence of slurry mortars in substrates of structural concretes. To optimize the microstructure of the interfacial transition zone of mortar and concrete and to improve the adherence of mortar renderings, slurry mortars of lower water/cement ratio with silica obtained from rice husk were used as treatment of interfacial transition zone. In order to evaluate adherence, bond strength tests were realized. The microstructural characterization of the interfacial transition zone of slurry mortars and concrete was performed by scanning electronic microscopy. The results indicate that adding silica obtained from rice husk into the slurry mortars increases the bond strength. Moreover, the formation of a dense microstructure is observed in the interfacial transition zone of slurry mortar and concrete due to the microfiller effect and high pozzolanic activity of the silica obtained from rice husk. The implementation of a connection bridge constituted by slurry mortars with the addition of the silica obtained from rice husk between the substrate and the mortar rendering showed to be efficient in the substrates with low porosity, as in the case of concrete structures.
46

Desempenho de argamassas de revestimentos produzidas com agregados reciclados oriundos do res?duo de constru??o e demoli??o da Grande Natal-RN / Performance of mortar coating produced with recycled aggregates derived from construction and demolition waste (CDW) produced in the Grande Natal-RN

Ara?jo, Neuber Nascimento de 28 March 2014 (has links)
Made available in DSpace on 2014-12-17T14:48:17Z (GMT). No. of bitstreams: 1 NeuberNA_DISSERT.pdf: 3614551 bytes, checksum: 214bf692c54f433fec3b97fdac3c0659 (MD5) Previous issue date: 2014-03-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The construction industry is responsible for generating a lot of waste because of their activities. Consequently, it is noticeable the occurrence of environmental problems in terms of its disposal in inappropriate places. Faced with this problem, some studies have been conducted with the aim of developing technologies and alternatives for recycling construction and demolition waste (CDW), motivated by the scarcity of natural resources and reduction of environmental problems generated. The research aims to characterize the recycled aggregates derived from construction and demolition waste (CDW) produced in the Greater Natal-RN and analyze the performance of mortar coating produced with recycled aggregates. The study includes the chemical , physical and microstructural characterization of recycled aggregates , as well as conducting microscopic analysis and laboratory tests in the fresh state (consistency index , water retention , bulk density and content of entrained air ) and in the hardened state ( compressive strength , tensile strength in bending , water absorption by immersion and capillary , mass density and void ratio ) for mortars produced from different levels of substitution of aggregates ( 0, 20 %, 40 %, 60 %, 80 % and 100 %). The results were satisfactory, providing mortars produced with recycled aggregates, smaller mass density and dynamic modulus values as well as an increase in the rates of absorption and porosity. The tensile strength in bending and compression for TP1 (1:2:8) trait were lower for mortars produced with recycled aggregates and the best result was 20% for replacement. For the TP2 (1:8) mapping, there was an increase in resistance to traction and compression and the best result was for 100% replacement of natural aggregates by recycled. The experiments led to the conclusion that the technical and economic point of view that the mortars produced with recycled aggregates can be used in construction, only if there is an effective control in production processes of recycled aggregate and at the dosage of mortars / A ind?stria da constru??o civil ? respons?vel por gerar uma grande quantidade de res?duos em fun??o de suas atividades, ocasionando problemas ambientais, econ?micos e sociais. Diante dessa problem?tica, alguns estudos v?m sendo realizados com o objetivo de desenvolver tecnologias e alternativas de reciclagem para os res?duos de constru??o e demoli??o (RCD), motivados pela escassez de recursos naturais e pela diminui??o dos problemas ambientais gerados. A pesquisa tem por objetivo caracterizar os agregados reciclados produzidos na Grande Natal-RN e analisar o desempenho de argamassas de revestimento produzidas com estes agregados. O estudo inclui a caracteriza??o qu?mica, f?sica e microestrutural dos agregados reciclados, assim como a realiza??o de an?lises microsc?picas e ensaios laboratoriais das argamassas no estado fresco (?ndice de consist?ncia, reten??o de ?gua, densidade de massa e teor de ar incorporado) e no estado endurecido (resist?ncia a compress?o, resist?ncia a tra??o na flex?o, absor??o de ?gua por imers?o e por capilaridade, densidade de massa e ?ndice de vazios), para argamassas produzidas a partir de diferentes teores de substitui??o de agregados (0, 20%, 40%, 60%, 80% e 100%). Os resultados obtidos foram satisfat?rios, proporcionando ?s argamassas produzidas com agregados reciclados, valores menores de densidade de massa e m?dulo de elasticidade din?mico, assim como um incremento nos ?ndices de absor??o e porosidade. A resist?ncia ? tra??o na flex?o e ? compress?o para o tra?o TP1 (1:2:8) foram inferiores para as argamassas produzidas com agregados reciclados e o melhor resultado foi para 20% de substitui??o. Para o tra?o TP2 (1:8), ocorreu um incremento na resist?ncia ? tra??o e ? compress?o e o melhor resultado foi para 100% de substitui??o dos agregados naturais pelos reciclados. Os experimentos conduziram a concluir que do ponto de vista t?cnico, as argamassas produzidas com agregados reciclados podem ser utilizadas na constru??o civil, desde que haja um controle eficiente nos processos de produ??o do agregado reciclado e na dosagem das argamassas
47

Argamassas do grupo escolar Augusto Severo/RN: caracteriza??o e incid?ncia de manifesta??es patol?gicas / Mortar from the grupo escolar Augusto Severo/RN: Characterization and incidence of pathological manifestations

Sousa, Adla Kellen Dionisio 30 May 2014 (has links)
Made available in DSpace on 2014-12-17T14:48:18Z (GMT). No. of bitstreams: 1 AdlaKDS_DISSERT.pdf: 6516382 bytes, checksum: bb93b728f29a7dc065eda95971bed62b (MD5) Previous issue date: 2014-05-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The search for cultural heritage preservation should be a constant, in order to minimize the lost of historical and cultural identity of a country. As part of this cultural heritage, highlights the importance of historical buildings. For the principles of restoration are met its important to know the state of conservation and the existing materials. Given the above, this work aims to study the pathological manifestations of the mortar coating from the Grupo Escolar Augusto Severo. For this, was conducted historical survey of the building, on-site visits with visual observation, collecting samples of mortar coating and characterization through visual and laboratory analysis, XRF, XRD, TG/DTG, OM and SEM-EDS. From the observations, pathological manifestations were found as: cracks, detachment of the coating, dirt, use of inappropriate material basis of cement, efflorescence, mold and mildew and also incompatible material base of cement. It was found that the pathological manifestations were intensified due to lack of coverage in some spots and especially the abandonment of the building, that many years does not have restoration or any other type of preventive and corrective maintenance. The results of laboratory tests indicated that the mortars studied are based on lime, with calcitic nature, and siliceous aggregate, with the presence of clay in two samples. From the samples collected, two are composed of lime, sand and clay and two by lime and sand. In this regard, it is important to conduct periodic inspections and maintenance, as well as carrying out restoration with use of material compatible with the original / A busca pela preserva??o do patrim?nio cultural deve ser uma constante, para que n?o haja a perda da identidade hist?rica e cultural de um pa?s. Como parte deste patrim?nio cultural, destaca-se a import?ncia das edifica??es hist?ricas. Para que os princ?pios de restauro sejam atendidos ? de suma import?ncia conhecer o estado de conserva??o desses bens e os materiais existentes. Diante do exposto, este trabalho tem como objetivo estudar as manifesta??es patol?gicas presentes nos revestimentos argamassados, bem como caracterizar as argamassas, de maior valor patrimonial, do Grupo Escolar Augusto Severo. Para isso, foi realizado um levantamento hist?rico da edifica??o, visitas in loco com observa??o visual e registro fotogr?fico, coleta de amostras de argamassas de revestimento e caracteriza??o por meio de an?lise visual e laboratorial, FRX, DRX, TG/DTG e MEV-EDS. A partir das observa??es realizadas, foram identificadas manifesta??es patol?gicas como: fissuras, desprendimento do revestimento, sujidade, efloresc?ncia, mofo e bolor, al?m da utiliza??o de material inadequado ? base de cimento. Constatou-se que as manifesta??es patol?gicas foram intensificadas devido ? falta de cobertura em alguns pontos e, sobretudo pelo abandono da edifica??o, que h? muitos anos n?o passa por restaura??o ou qualquer outro tipo de manuten??o preventiva e corretiva. Os resultados das t?cnicas em laborat?rio indicaram que as argamassas estudadas s?o ? base de cal, de natureza calc?tica, e agregado silicoso, com presen?a de argila em duas amostras. Das amostras coletadas, duas s?o compostas por cal, areia e argila e duas por cal e areia. Neste sentido, ressalta-se que ? de relevante import?ncia a realiza??o de inspe??es e manuten??es peri?dicas, bem como a realiza??o de restaura??o com a utiliza??o de material compat?vel com o original
48

Avaliacao do comportamento frente a corrosao pelo ataque de cloreto de argamassa armada apos varios tratamentos protetores

CRIVELARO, MARCOS 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:46:53Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:47Z (GMT). No. of bitstreams: 1 08513.pdf: 9974543 bytes, checksum: 92f7076f974608407acb3c472a6d993b (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
49

Estudo da durabilidade de argamassas utilizando cinzas e casca de arroz. / Study of the durability of mortars using ash and husk of rice.

SOUZA, Jozilene de. 05 October 2018 (has links)
Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-10-05T14:15:18Z No. of bitstreams: 1 JOZILENE DE SOUZA - TESE (PPGEP) 2008.pdf: 3086749 bytes, checksum: d738b230b5a0dcf70a631cd0699b9989 (MD5) / Made available in DSpace on 2018-10-05T14:15:18Z (GMT). No. of bitstreams: 1 JOZILENE DE SOUZA - TESE (PPGEP) 2008.pdf: 3086749 bytes, checksum: d738b230b5a0dcf70a631cd0699b9989 (MD5) Previous issue date: 2008-12-19 / O Brasil está, atualmente, entre os maiores produtores de grãos do mundo, em especial o arroz. Com o beneficiamento deste produto são geradas grandes quantidades de resíduos (casca) que ocasionam problemas ambientais, pela deposição inadequada no meio ambiente e por seu longo tempo de degradação. A incorporação destes resíduos industriais a componentes para construção civil, como concretos e argamassas, é uma das possíveis soluções para o aproveitamento de subprodutos poluentes estando em acordo com os princípios da sustentabilidade. Este trabalho tem como objetivo estudar a durabilidade de argamassas convencionais e alternativas incorporadas com resíduos de cinza da casca de arroz substituindo parte do aglomerante e casca de arroz substituindo o agregado miúdo, através do envelhecimento acelerado, por ciclos de molhagem e secagem. Inicialmente foi realizada com as matérias-primas convencionais e alternativas uma caracterização física, química e mineralógica através dos seguintes ensaios: análise granulométrica por peneiramento e difratometria a laser, área especifica, massa unitária, análise química, difração de raios X, análise térmica diferencial e gravimétrica. Para avaliar a durabilidade pelo método do envelhecimento acelerado, por ciclos de molhagem e secagem, foram confeccionados corpos-deprova de argamassas convencionais e argamassas alternativas nos traços 1:4; 1:6 e 1:8 incorporando 3%, 6%, 9%, 15%, 20% e 30% de resíduo de cinza de casca de arroz em substituição ao aglomerante e 10%, 20% e 30% de casca de arroz em substituição ao agregado miúdo por períodos de cura de 28, 63, 91, 180 e 360 dias. As propriedades físico-mecânicas determinadas foram: absorção de água, densidade aparente e resistência. Os resultados dos ensaios de caracterização das matérias-primas convencionais (cimento e agregado miúdo) e alternativos (cinza e casca de arroz) encontram-se dentro dos padrões estabelecidos pelas normas da ABNT, indicando superfície específica e índice de finura da cinza de casca de arroz bem superior a do cimento empregado. Os resultados evidenciaram que a cinza de casca de arroz é predominantemente amorfa e tem alta pozolanicidade de acordo com as especificações da ABNT, possibilitando seu uso em concretos e argamassas pelas suas características de grande finura. Em relação ao comportamento mecânico, foram encontrados valores superiores dos corpos-de-prova alternativos incorporados com cinza de casca de arroz em relação aos convencionais mesmo quando expostos ao envelhecimento acelerado, enquanto os corpos-de-prova das argamassas incorporados com casca de arroz apresentaram valores dentro das especificações da ABNT e inferiores aos convencionais, comprovando a viabilidade técnica da utilização destes resíduos,uma vez que não se evidenciou influência na durabilidade, além de ser uma medida ecologicamente correta. / Brazil is one of the greatest producers of grain in the world, especially in rice. With the industrialization of this product great amount of waste (husk) is generate and cause environmental problems, by the inadequate discharge in the environment and by the long time to deteriorate. The incorporation of this industrial residue as components to civil construction, as concrete and mortars, is one of the possible solutions to use this pollutants sub products and this is in agreement with the sustainable principle. The aim of this work is to study the durability of the conventional and alternative mortars incorporated with husk rice ash residue by substituting part of the agglomerate and rice husk substituting small aggregate. The durability was study by the accelerate weathering (by wetting and drying cycles). Firstly it was done a physical, chemical and mineralogical characterization of the conventional and alternatives raw materials by the following techniques: particle size by sieving and laser diffraction, surface area, specific mass, chemical analysis, X-rays diffraction, differential thermal analysis and gravimetry. The pozzolanic activity was measured according to the BNT NBR 12653(1997) norm. To evaluate the durability by the accelerate weathering (wetting and drying cycles) it was made body sample with conventional and alternative mortars with traces of 1:4; 1:6 e 1:8 incorporated with 3%, 6%, 9%,15%, 20% and 30% of ash rice husk residue in substitution of agglomerate and 10%, 20% and 30% of rice husk in substitution to small aggregate, for cure period of 28, 63, 91, 180 and 360 days. The physical and mechanical properties were: water absorption, apparent density,mechanical resistance and mass loss. The results of the conventional (cement and small aggregate) and alternative (ash and husk rice) raw materials characterization are in the standard values established by ABNT norms, indicating surface area and amount of fine particles of the husk rice ash are superior to the cement used. The results put in evidence that the husk rice ash is predominantly amorphous and has high pozzolanicity according to the specifications of the ABNT. This makes possible the use of this ash in concrete and mortars due to the great amount of fine particles. In relation to the mechanical properties, the results shown values superior to the body samples incorporated with husk rice in relation to the conventional even when exposed to the accelerate weathering. To the body samples incorporated with husk rice presented values according to the ABNT specifications and inferior to the conventional ones. It was concluded that the use of these residues are technical viable once did not present influence in the durability and also is an ecological correct action.
50

Proposta de formulação de argamassas para assentamento e revestimento de paredes e tetos com incorporação de pó de exaustão de fundição / Proposed formulation with casting waste powder for laying and covering mortars

Pereira, Helena Ravache Samy 18 August 2014 (has links)
Made available in DSpace on 2016-12-08T15:56:17Z (GMT). No. of bitstreams: 1 resumo tese.pdf: 15008 bytes, checksum: b3fcb8e618165bdab7dabdeefc264a32 (MD5) Previous issue date: 2014-08-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The use of casting waste powder from industry in mortars brings environmental benefits by minimizing the impact caused by the disposal of waste on the environment. Casting exhaust powder is a waste product from the regeneration of sand molds from the core making process sector from a foundry industry located in Joinville/SC. This work aims to propose a formulation method for laying mortars, and wall and ceiling coating mortars incorporating casting waste powder whose use would result in a product with adequate technical performance. The fine aggregates, the casting waste powder and mortars were characterized by standard assays, electron microscopy and X-ray powder diffraction. The laying and coating mortar compositions were based on a system of equations obtained using the mixture design methodology. Through this study, results of experimental character and a method for formulating mortars that can be useful in the construction sector were obtained, thus contributing to a better understanding of the use of casting waste in mortars. / O uso de resíduos de fundição como o pó de exaustão em argamassas traz benefícios ambientais através da minimização do impacto causado pelo descarte do resíduo no meio ambiente. O pó de exaustão de fundição é um resíduo proveniente da regeneração dos moldes de areias do setor de macharia de uma indústria de fundição localizada em Joinville/SC. Este trabalho tem por objetivo propor um método de formulação para argamassas de assentamento e revestimento de paredes e tetos com incorporação de pó de exaustão cuja utilização resulte em um produto com desempenho técnico adequado. Os agregados miúdos, o resíduo pó de exaustão de fundição e as argamassas foram caracterizados por ensaios normalizados, microscopia eletrônica e difração de raios-X. As composições das argamassas em massa foram obtidas através de planejamento de experimentos de delineamento por misturas. A proposta de formulação de argamassas de assentamento e revestimento de paredes e tetos foi baseada na resolução de sistemas de equações obtidas através do modelamento estatístico das propriedades. Por meio deste estudo, foram obtidos resultados de caráter experimental e um método de formulação de argamassas que podem ser úteis ao setor de construção civil, contribuindo desta forma com o melhor entendimento do uso de resíduos de fundição em argamassas.

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