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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.
51

Thermally insulating carbon foams from carbonized kraft lignin / Värmeisolerande kolskum från karboniserat kraftlignin

Hernodh Svantesson, Isabelle January 2021 (has links)
Kolmaterial, såsom kolfibrer och kolskum, används som värmeisolatorer i applikationer vid höga temperaturer. För närvarande härleds dessa material från fossilbaserade källor, vilket tyder på ett behov av att hitta alternativa kandidater baserade på förnybara källor. Detta examensarbete undersökte möjligheten att använda kraftlignin som ett förnyelsebart startmaterial för framställning av kolskum med värmeisoleringsegenskaper. Två kraftligniner av barrträd med olika molekylvikter och ett kraftlignin av lövträd användes. De tre kraftligninerna karboniserades vid 1000°C efter att ha blandats i olika förhållanden och kombinationer (formuleringen av råmaterialet). Formuleringen av råmaterialet påverkade densiteten och porositeten hos de erhållna materialen, vilket i sin tur ledde till skillnader i kompressionsstyrkan och värmeledningsförmågan hos de erhållna kolskummen. Kolskummen hade olika värmeledningsförmåga (0,11-0,35 W/mK), porositet (80,55-97,53%) och densitet (0,08-0,42 g/cm3). För skummet med den högsta densiteten uppskattades krossstyrkan till cirka 10,03 MPa vilket är jämförbart med kommersiellt använda kolskum för högtemperaturisolerande applikationer. Kolskummens värmeledningsförmåga var inom omfånget för kommersiellt använda kolskum för högtemperaturapplikationer. Detta arbete visar möjligheten att tillverka kolskum från 100% kraftlignin som har liknande egenskaper som kommersiellt tillgängliga termiska isoleringsmaterial för högtemperaturapplikationer. / Carbon materials, such as carbon fibres and carbon foams, are used as thermal insulators in high-temperature applications. At present, these materials are derived from fossil-based sources, which suggests a need of finding alternatives candidates based on renewables. This thesis work investigated the possibility of using kraft lignin as a renewable starting material for the preparation of carbon foams with thermal insulation properties. Two softwood kraft lignins with different molecular weights and a hardwood kraft lignin were used. The three kraft lignins were carbonized at 1000°C after being mixed in different ratios and combinations (precursor formulation). The precursor formulation affected the density and porosity of the obtained materials, which in turn led to differences in compression strength and thermal conductivity of the carbon foams derived. The obtained carbon foams had different thermal conductivities (0.11-0.35 W/mK), porosity (80.55-97.53%) and density (0.08-0.42 g/cm3). For the foam with the highest density, the crushing strength was estimated to approximately 10.03 MPa which is comparable to commercially used carbon foams for high-temperature insulating applications. The thermal conductivity of the prepared carbon foams was in the range of commercially used carbon foams for high-temperature applications. This work demonstrates the possibility of preparing carbon foams from 100% kraft lignin which has properties similar of commercially available insulating materials for high-temperature applications.
52

Hasičská stanice / Fire station

Horváthová, Radka January 2022 (has links)
The topic of the diploma thesis is the elaboration of project documentation for the construction of a fire station with almost zero energy consumption. The building will serve as a fire station type P4 with the scope of the JPO I unit - a unit of the fire department with a territorial scope, usually within 20 minutes drive from the place of deployment. The designed building is a detached object with two above-ground and one underground floor. The building is designed as a reinforced concrete skeleton. It consists of two operating units. The administrative and operational part has three floors. In this part, the main entrance to the building is on the 1st floor, oriented on the south side. The technical rooms of the fire department are located on the first floor and are functionally connected to the administrative part. Exit garages, a car wash and a dryer are also attached to it. Prior to the elaboration of the project, a visit to the regional fire station in Trnava and a consultation with the director of this station took place regarding the needs and requirements of the fire department.
53

Polyfunkční dům / multifunctional building

Šelep, Miroslav January 2022 (has links)
The subject of this diploma thesis is structural and constructional design of a new multifunctional building in Spišská Belá. It is a new detached building structure with one basement floor and three above-ground floors, designed on a plot number 1859 in cadastre unit Spišská Belá. The designed building is constructed of clay masonry system with contact thermal insulation and supported by strip foundations. Ceiling constructions of above-ground floors are made of prefabricated components. The basement ceiling is made of reinforced concrete. Object is roofed by saddle roof set on wooden roof truss. There are four three room flats, one accessible flat, bicycle shop and flats facilities, situated in the building. The focus during development was on wheelchair access.
54

Att bygga fuktsäker källargrund enligt olika krav / To build moisture proof basement according to different requirements

Timosson, Anton, Loftby, Alexander January 2017 (has links)
Vid byggande av hus med källargrund vill de flesta kunna använda den ytan som en del av bostaden samt för aktiviteter såsom olika hobbyverksamheter. När källaren nyttjas som bostad krävs fuktskydd och värmeisolering i golv och väggar. Man vill ha en torr källare så möjlighet att välja ytskikt finns.När man väljer material i källaryttergrundmuren väljer man med hänsyn till överbyggnadens konstruktion. Exempel på material är murad vägg av betonghålblock, murad vägg av lättbetongblock, murad vägg av lättklinkerblock, platsgjuten betong, stående källarväggselement av lättbetong, stående källarväggselement av lättklinker och betongelement. Är det ett flerbostadshus med källaryttergrundmur byggs det nästan enbart av platsgjuten betong medan det vid småhus i regel utförs av lättbetong, lättklinker samt element av lättbetong och lättklinkerbetong.Utöver material för den bärande konstruktionen måste även material för tilläggsisolering och fuktisolering väljas. Utan isoleringen uppfyller inte byggnaden de energikrav som finns. Likaså måste de flesta ytterväggrundmurar förses med någon typ av fuktisolering. Vad är då det bästa sättet att bygga en fuktsäker källare med eventuellt tillkommande krav? / When building houses with a basement, most people want to use that area as part of the accommodation as well as activities such as various hobby activities. When the basement is used like the rest of the house, as a warm living area, moisture protection and thermal insulation are required in both floors and walls. One wants a dry basement so the possibility of choosing surface layers is available.When selecting materials within the basement wall, it is with regards of the construction above. Examples of materials are brick walls of concrete boulders, brick walls of aerated concrete, brick walls of haydite blocks, cast concrete, standing concrete wall elements of aerated concrete, standing brick wall elements of haydite and concrete elements. If it is a multi-storey house with basement terraced ground, it is almost exclusively made of cast concrete, but for individual buildings it is usually made of aerated concrete, haydite and elements of aerated concrete and haydite concrete.In addition to material for the supporting structure, additional insulation and moisture insulation materials must also be selected. Without isolation, the building does not meet the energy requirements. Likewise, most exterior walls must be provided with some type of moisture insulation. What is then the best way to build a moisture proof basement with any additional requirements?
55

Vibro-acoustic products from re-cycled raw materials using a cold extrusion process. A continuous cold extrusion process has been developed to tailor a porous structure from polymeric waste, so that the final material possesses particular vibro-acoustic properties.

Khan, Amir January 2008 (has links)
A cold extrusion process has been developed to tailor a porous structure from polymeric waste. The use of an extruder to manufacture acoustic materials from recycled waste is a novel idea and the author is not aware of any similar attempts. The extruder conveys and mixes the particulates with a reacting binder. The end result is the continuous production of bound particulates through which a controlled amount of carbon dioxide gas that is evolved during the reaction is used to give the desired acoustic properties. The cold extrusion process is a low energy consuming process that reprocesses the post manufacturing waste into new vibro-acoustic products that can be used to meet the growing public expectations for a quieter environment. The acoustical properties of the developed products are modelled using Pade approximation and Johnson-Champoux-Allard models. Applications for the developed products are widespread and include acoustic underlay, insulation and panels in buildings, noise barriers for motorways and railway tracks, acoustic insulation in commercial appliances and transport vehicles.
56

Acoustic and Thermal Properties of Recycled Porous Media

Mahasaranon, Sararat January 2011 (has links)
This thesis is concerned with developing porous materials from tyre shred residue and polyurethane binder for acoustic absorption and thermal insulation applications. The resultant materials contains a high proportion of open, interconnected cells that are able to absorb incident sound waves through viscous friction, inertia effects and thermal energy exchanges. The materials developed are also able to insulate against heat by suppressing the convection of heat and reduced conductivity of the fluid locked in the large proportion of close-cell pores. The acoustic absorption performance of a porous media is controlled by the number of open cells and pore size distribution. Therefore, this work also investigates the use of catalysts and surfactants to modify the pore structure and studies the influence of the various components in the chemical formulations used to produce these porous materials. An optimum type and amounts of catalyst are selected to obtain a high chemical conversion and a short expanding time for the bubble growth phase. The surfactant is used to reduce the surface tension and achieve a homogenous mixing between the solid particulates tyre shred residue, the water, the catalyst and the binder. It is found that all of the components significantly affect the resultant materials structure and its morphology. The results show that the catalyst has a particularly strong effect on the pore structure and the ensuing thermal and acoustical properties. In this research, the properties of the porous materials developed are characterized using standard experimental techniques and the acoustic and thermal insulation performance underpinned using theoretical models. The important observation from this research is that a new class of recycled materials with pore stratification has been developed. It is shown that the pore stratification can have a positive effect on the acoustic absorption in a broadband frequency range. The control of reaction time in the foaming process is a key function that leads to a gradual change in the pore size distribution, porosity, flow resistivity and tortuosity which vary as a function of sample depth. It is shown that the Pade approximation is a suitable model to study the acoustic behaviour of these materials. A good agreement between the measured data and the model was attained. / Ministry of Science and Technology of Thailand; Naresuan University, Phitsanulok, Thailand,
57

Fabrication de semiconducteurs poreux pour améliorer l'isolation thermique des MEMS

Newby, Pascal January 2014 (has links)
Résumé : L’isolation thermique est essentielle dans de nombreux types de MEMS (micro-systèmes électro-mécaniques). Elle permet de réduire la consommation d’énergie, améliorer leurs performances, ou encore isoler la zone chaude du reste du dispositif, ce qui est essentiel dans les systèmes sur puce. Il existe quelques matériaux et techniques d’isolation pour les MEMS, mais ils sont limités. En effet, soit ils ne proposent pas un niveau d’isolation suffisant, sont trop fragiles, ou imposent des contraintes trop importantes sur la conception du dispositif et sont difficiles à intégrer. Une approche intéressante pour l’isolation, démontrée dans la littérature, est de fabriquer des pores de taille nanométrique dans le silicium par gravure électrochimique. En nanostructurant le silicium ainsi, on peut diviser sa conductivité thermique par un facteur de 100 à 1000, le transformant en isolant thermique. Cette solution est idéale pour l’intégration dans les procédés de fabrication existants des MEMS, car on garde le silicium qui est déjà utilisé pour leur fabrication, mais en le nanostructurant localement, on le rend isolant là où on en a besoin. Par contre sa porosité cause des problèmes : mauvaise résistance chimique, structure instable au-delà de 400°C, et tenue mécanique réduite. La facilité d’intégration des semiconducteurs poreux est un atout majeur, nous visons donc de réduire les désavantages de ces matériaux afin de favoriser leur intégration dans des dispositifs en silicium. Nous avons identifié deux approches pour atteindre cet objectif : i) améliorer le Si poreux ou ii) développer un nouveau matériau. La première approche consiste à amorphiser le Si poreux en l’irradiant avec des ions à haute énergie (uranium, 110 MeV). Nous avons montré que l’amorphisation, même partielle, du Si poreux entraîne une diminution de sa conductivité thermique, sans endommager sa structure poreuse. Cette technique réduit sa conductivité thermique jusqu’à un facteur de trois, et peut être combinée avec une pré-oxydation afin d’atteindre une réduction d’un facteur cinq. Donc cette méthode permet de réduire la porosité du Si poreux, et d’atténuer ainsi les problèmes de fragilité mécanique causés par la porosité élevée, tout en gardant un niveau d’isolation égal. La seconde approche est de développer un nouveau matériau. Nous avons choisi le SiC poreux : le SiC massif a des propriétés physiques supérieures à celles du Si, et donc à priori le SiC poreux devrait conserver cette supériorité. La fabrication du SiC poreux a déjà été démontrée dans la littérature, mais avec peu d’études détaillées du procédé. Sa conductivité thermique et tenue mécanique n’ont pas été caractérisées, et sa tenue en température que de façon incomplète. Nous avons mené une étude systématique de la porosification du SiC en fonction de la concentration en HF et le courant. Nous avons implémenté un banc de mesure de la conductivité thermique par la méthode « 3 oméga » et l’avons utilisé pour mesurer la conductivité thermique du SiC poreux. Nous avons montré qu’elle est environ deux ordres de grandeur plus faible que celle du SiC massif. Nous avons aussi montré que le SiC poreux est résistant à tous les produits chimiques typiquement utilisés en microfabrication sur silicium. D’après nos résultats il est stable jusqu’à au moins 1000°C et nous avons obtenu des résultats qualitatifs encourageants quant à sa tenue mécanique. Nos résultats signifient donc que le SiC poreux est compatible avec la microfabrication, et peut être intégré dans les MEMS comme isolant thermique. // Abstract : Thermal insulation is essential in several types of MEMS (micro electro-mechanical systems). It can help reduce power consumption, improve performance, and can also isolate the hot area from the rest of the device, which is essential in a system-on-chip. A few materials and techniques currently exist for thermal insulation in MEMS, but these are limited. Indeed, either they don’t have provide a sufficient level of insulation, are too fragile, or restrict design of the device and are difficult to integrate. A potentially interesting technique for thermal insulation, which has been demonstrated in the literature, is to make nanometer-scale pores in silicon by electrochemical etching. By nanostructuring silicon in this way, its thermal conductivity is reduced by a factor of 100 to 1000, transforming it into a thermal insulator. This solution is ideal for integration in existing MEMS fabrication processes, as it is based on the silicon substrates which are already used for their fabrication. By locally nanostructuring these substrates, silicon is made insulating wherever necessary. However the porosity also causes problems : poor chemical resistance, an unstable structure above 400◦C, and reduced mechanical properties. The ease of integration of porous semiconductors is a major advantage, so we aim to reduce the disadvantages of these materials in order to encourage their integration in silicon-based devices. We have pursued two approaches in order to reach this goal : i) improve porous Si, or ii) develop a new material. The first approach uses irradiation with high energy ions (100 MeV uranium) to amorphise porous Si. We have shown that amorphisation, even partial, of porous Si leads to a reduction of its thermal conductivity, without damaging its porous structure. This technique can reduce the thermal conductivity of porous Si by up to a factor of three, and can be combined with a pre-oxidation to achieve a five-fold reduction of thermal conductivity. Therefore, by using this method we can use porous Si layers with lower porosity, thus reducing the problems caused by the fragility of high-porosity layers, whilst keeping an equal level of thermal insulation. The second approach is to develop a new material. We have chosen porous SiC: bulk SiC has exceptional physical properties and is superior to bulk Si, so porous SiC should be superior to porous Si. Fabrication of porous SiC has been demonstrated in the literature, but detailed studies of the process are lacking. Its thermal conductivity and mechanical properties have never been measured and its high-temperature behaviour has only been partially characterised. We have carried out a systematic study of the effects of HF concentration and current on the porosification process. We have implemented a thermal conductivity measurement setup using the “3 omega” method and used it to measure the thermal conductivity of porous SiC. We have shown that it is about two orders of magnitude lower than that of bulk SiC. We have also shown that porous SiC is chemically inert in the most commonly used solutions for microfabrication. Our results show that porous SiC is stable up to at least 1000◦C and we have obtained encouraging qualitative results regarding its mechanical properties. This means that porous SiC is compatible with microfabrication processes, and can be integrated in MEMS as a thermal insulation material.
58

Análise da resistência residual de compressão de blocos, prismas e pequenas paredes de alvenaria estrutural de blocos de concreto submetidos à situação de incêndio / Residual compressive strength of blocks, prisms and walls of concrete structural masonry under fire situation.

Dupim, Rafael Henrique 03 June 2019 (has links)
Alvenaria estrutural é um sistema construtivo em que paredes exercem tanto função estrutural como de vedação. Apesar de ser largamente utilizada no Brasil atualmente, não há uma norma nacional com procedimentos para o dimensionamento deste sistema em situação de incêndio. Muito se deve pelo fato de as pesquisas nesta área serem substancialmente escassas se comparadas com os sistemas construtivos em concreto armado ou aço. Neste contexto, este trabalho tem por objetivo realizar ensaios experimentais para avaliar a resistência residual de compressão da alvenaria estrutural com blocos de concreto. Foram avaliadas duas variações de blocos de concreto, com resistências características de 4,0 e de 10,0 MPa, ambos com espessura nominal de 140 mm e os corpos de prova estudados foram os prismas e as pequenas paredes. Realizou-se a caracterização física, geométrica e mecânica da alvenaria em temperatura ambiente e na sequência os corpos de prova foram submetidos a uma simulação de incêndio-padrão normalizado pela ISO 834-1:1999, durante 120 minutos que é o TRRF máximo recomendado pela ABNT NBR 14432:2001. Na primeira fornada foram avaliados os elementos de 140 mm sem revestimento e segunda fornada todos os elementos revestidos com uma camada de 5 mm de gesso. Após o resfriamento lento até a temperatura ambiente, os corpos de prova foram submetidos ao ensaio de compressão simples para avaliar a resistência residual de compressão dos blocos, prismas e pequenas paredes. Em todos os casos as resistências encontradas ficaram abaixo do suficiente para garantir a segurança durante a ação de um incêndio, uma vez que o máximo de resistência residual encontrado foi de 22%. A influência da compartimentação na resistência residual das pequenas paredes, foi brevemente avaliada, para isso três pequenas paredes de 4,0 MPa e 140 mm com o interior isolado dos gases externos foram submetidas ao incêndio-padrão e compressão pós resfriamento, verificou-se que a perda de resistência neste caso foi de 54% enquanto nas pequenas paredes com fogo em todas as faces e expostas ao fogo pelo mesmo período a perda foi de 86%. Estas pequenas paredes compartimentadas foram instrumentadas com a finalidade de avaliar a transferência de calor ao longo da sessão transversal e verificar o tempo de atendimento do critério de isolamento, que neste caso foi de 62 minutos, abaixo do TRRF máximo de 120 minutos. / Structural masonry is a building system that walls work as structure and has sealing function too. Even though it is widely used in Brazil nowadays, there is no national standardization for the masonry design in fire situation. One of the reasons is that researches in this area are substantially sparse if compared with other building systems like reinforced concrete and steel. In this context, the purpose of this work is to evaluate the residual compressive strength of concrete structural masonry by experimentally tests. Two concrete block variations were evaluated, with strengths of 4,0 and 10,0 MPa, both with 140 mm nominal thickness, the elements studied were prisms and walls, beyond blocks. In the first stage, the masonry was characterized in ambient temperature and in the second stage, the elements were submitted to fire simulation standardized by ISO 834-1: 1999 for 120 minutes, which is the maximum TRRF recommended by ABNT NBR 14432: 2001. In the first fire simulation the 140 mm elements were evaluated without covering and in the second one, all the elements were covered with 5 mm layer of plaster. Then, after slow cooling until ambient temperature, the residual compressive strength of the blocks, prisms and walls was evaluated by compression test. In all cases the resistances were not enough to ensure safety during the fire, since the maximum residual resistance found was 22%. Still in this stage, the influence of the compartmentation on the residual resistance of the walls was briefly evaluated. Three walls of 4.0 MPa and 140 mm were placed in a triangle that was thermally insulated inside, and after the fire simulation were subjected in a post-cooling compression test. The loss of resistance found in this case was 54% while in the walls with fire on all faces and exposed to fire for the same period the loss was 86%. These compartmentalized walls were instrumented with the purpose of evaluating the heat transfer along the cross section and to check the time of the isolation criterion attendance, which in this case was 62 minutes, below the 120-minute established as maximum TRRF.
59

Painéis de resíduos madeireiros e de borracha de pneu associados à espuma poliuretana à base de mamona para aplicação como composições termoacústicas / Panels from wood and tire rubber wastes associated with castor-oil-based polyurethane foam for application as thermo-acoustic compositions

Bertolini, Marília da Silva 04 September 2014 (has links)
Questões ligadas ao desempenho térmico e acústico de edificações têm sido cada vez mais abordadas, num cenário em que ganham importância a economia de energia e o controle do ruído. O advento dos materiais compósitos propiciou o emprego de resíduos de processos que, aliados a materiais de origem renovável, contribuem para a obtenção de produtos de reduzido impacto ambiental. Neste contexto, o presente trabalho teve como objetivo a produção e caracterização de painéis de partículas e espuma poliuretana à base de óleo de mamona, para destinação em composições termoacústicas. Os painéis de partículas foram produzidos utilizando-se resíduos de madeira de Pinus sp., tratado com CCB (preservante de cromo, cobre e boro - base óxido), borracha de pneus inservíveis e adesivo poliuretano à base de óleo de mamona. Foram adotadas variações na produção dos painéis, quanto aos fatores: proporção e configuração da borracha, espessura e pressão de prensagem; verificando sua influência no desempenho dos painéis. As propriedades físicas e mecânicas dos painéis foram determinadas conforme a ABNT NBR 14810-3 (2006) e avaliadas segundo os principais requisitos de normas neste âmbito. Análises estatísticas (ANOVA) foram realizadas para verificação da influência dos fatores de produção, e de suas interações, nas propriedades físicas e mecânicas dos painéis. Também foram avaliadas a morfologia e estabilidade térmica dos painéis e espumas. O isolamento térmico foi avaliado pela determinação experimental da condutividade térmica. A absorção sonora dos painéis e espumas, em diferentes montagens, foi determinada por medições em câmara reverberante, conforme ISO 354 (1985). Os resultados das propriedades físicas e mecânicas dos painéis estiveram em grande parte condizentes com os documentos normativos. O teor de borracha e a sua interação com os demais fatores apresentaram influência estatística nas propriedades físicas e mecânicas dos painéis. A morfologia dos painéis e espumas permitiu visualizar sua adequação aos produtos propostos, por meio da porosidade. Em relação ao isolamento térmico e absorção sonora, os painéis e espumas, bem como as composições formadas, apresentaram desempenho coerente com produtos e normas utilizados como referência. Sendo assim, verificou-se a viabilidade de produção e aplicação dos painéis e espuma poliuretana à base de mamona em composições destinadas ao conforto termoacústico. / Issues relating to thermal and acoustic performance of buildings have been increasingly addressed in a scenario where energy savings and noise control are essential. Advent of composite materials enabled the use of residues from production processes that, coupled with renewable source materials, contribute to obtain products with low environmental impact. So, this study aimed to the production and characterization of particleboards and castor-oil-based polyurethane foam, for thermo-acoustic compositions. Panels were produced with residues of Pinus sp., treated with CCB (chromium, copper and boron basic oxide preservative), tire rubber wastes and castor-oil-based polyurethane adhesive. Variations in the production parameters were adopted: proportion and configuration of tire rubber; panels thickness; and pressing pressure, to determine their influence on panel performance. Physical and mechanical properties of particleboards were determined based on ABNT NBR 14810-3 (2006) and evaluated according to the main requirements of standards in this area. Statistical analysis (ANOVA) was performed to check the influence of production factors, and their interactions, in those properties. Morphology and thermal stability of foams and panels were also evaluated. Thermal insulation was evaluated by experimental values of thermal conductivity. Sound absorption of the panels and foams, in different assemblies, was determined by measurement in a reverberation room, according to ISO 354 (1985). Results of evaluated panel properties were consistent with the normative requirements. The tire rubber content and its interaction with other factors influenced in almost all physical and mechanical properties of the particleboards. Morphology of the foams and panels permitted confirming their suitability to the proposed product by the porosity. With respect to thermal insulation and sound absorption, panels and foams as well as the correspondent compositions showed performance consistent to the references. Therefore, it was demonstrated the production feasibility and applying of studied compositions intended for the thermo-acoustic comfort.
60

Avaliação da utilização de isolantes térmicos no interior das cavidades de blocos cerâmicos componentes de alvenarias de vedação externa para o clima de São Leopoldo, RS

Brenner, Bruna Liliane 14 March 2017 (has links)
Submitted by JOSIANE SANTOS DE OLIVEIRA (josianeso) on 2017-06-05T14:55:48Z No. of bitstreams: 1 Bruna Liliane Brenner_.pdf: 2490760 bytes, checksum: 60445eff926b3f639cef6a24f01ba88f (MD5) / Made available in DSpace on 2017-06-05T14:55:48Z (GMT). No. of bitstreams: 1 Bruna Liliane Brenner_.pdf: 2490760 bytes, checksum: 60445eff926b3f639cef6a24f01ba88f (MD5) Previous issue date: 2017-03-14 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A necessidade da minimização dos impactos ambientais causados pelas mais diversas atividades humanas fica mais evidente a cada ano. Esta realidade leva pesquisadores a buscar alternativas para a otimização do uso de recursos naturais como a água e a energia. A energia proveniente de fontes hidrelétricas e termoelétricas é um recurso largamente consumido no Brasil, em grande parte pelas edificações. Diversas discussões a respeito da ampliação da eficiência energética nos edifícios levam, consequentemente, à questão do desempenho térmico. Em alternativa às soluções para ampliação do desempenho térmico com custo elevado, exigência de mão de obra especializada e acréscimo de tempo ao cronograma da obra em edificações, esta pesquisa teve como objetivo analisar o efeito do uso de isolantes térmicos no interior das cavidades dos blocos cerâmicos componentes da alvenaria. Esta apresenta-se como uma opção de isolamento facilitada em relação a outras técnicas conhecidas no mercado. O estudo foi realizado através de análises em protótipos de escala reduzida. Foram construídos quatro protótipos experimentais na cidade de São Leopoldo, RS sendo um deles utilizado como referência, representando a forma convencional de construção da alvenaria de blocos e os demais com as cavidades de seus blocos constituintes preenchidas com três diferentes tipos de isolantes térmicos: Esferas soltas de EPS, EPS de baixa densidade e perlita expandida. Nesta pesquisa foi utilizado EPS em forma de resíduo de uma empresa da região. Após a realização da pesquisa, coleta de dados e análise dos resultados verificou-se que os protótipos com isolamento apresentaram oscilações térmicas diárias minimamente menores em relação ao referência sendo as mais baixas obtidas pelo protótipo com preenchimento em EPS de baixa densidade, seguido pela perlita expandida e EPS em esferas. Apesar disto devido ao fato de estas terem sido muito pequenas não é possível afirmar que a utilização de isolantes térmicos no interior das cavidades de blocos cerâmicos constituintes da alvenaria pode trazer benefícios para o desempenho térmico em edificações em escala real. A utilização de isolantes em forma de resíduos apresentou-se como uma alternativa para reduzir custos com isolamento. / The need to minimize the environmental impacts caused by the most diverse human activities is more evident each year. This reality leads researchers to seek alternatives for optimizing the natural resources use such as water and energy. Energy from hydroelectric and thermoelectric sources is a widely used resource in Brazil, largely by buildings. Several discussions about increase energy efficiency in buildings therefore lead to the issue of thermal performance. As an alternative to solutions to increase the thermal performance with high cost, demand of specialized labor and increase of time to the work schedule in buildings, this research had as objective to analyze the effect of the use of thermal insulation inside the cavities of the ceramic blocks components of masonry. This is presented as an easier insulation option in relation to other techniques known in the market. The study was carried out through small scale prototype analyzes. Four experimental prototypes were constructed in São Leopoldo, RS, one of them being used as reference, representing the conventional construction form of the blocks masonry and the others with the cavities of its constituent blocks filled with three different thermal insulation types: EPS spheres, low density EPS and expanded perlite. In this research EPS was used in waste form from a company in the region. After the research, data collection and the results analysis, it was verified that the prototypes with insulation presented daily thermal oscillations minimally smaller in relation to the reference, being the lowest ones obtained by the prototype with low density EPS filling, followed by the expanded perlite and EPS spheres. Despite the fact that these diferences were very small, it is not possible to state that the use of thermal insulation inside the ceramic block cavities constituent of the masonry can bring benefits to the thermal performance in real buildings. The use of insulators in the form of residues was presented as an alternative to reduce costs with insulation.

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