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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.
91

The effect of freezing on hydraulic-cement mortar different hours after mixing

Bales, Eugene Dean, Price, Albert Earl January 1947 (has links)
As was stated before, the purpose of this problem was to find out the effect of freezing on mortar at different hours after mixing. This was a continuation of the work done by G.H. Harris in 1945. It was hoped that by using different materials, steel molds, and by molding, freezing and testing the specimens as accurately as was possible to do so with the equipment available the peculiar results obtained by Harris could either be verified or disproved. The results obtained by this problem were very irregular but did show a slight trend and did not show the great difference in strength over a short period of time as was shown by Harris’s results. To get a definite answer a large number of samples should be run for each different time of set before freezing. A large variety of materials should be used and it is also believed that test cylinders 6”x12” would give better results. / Master of Science
92

Performance Criteria Recommendations for Mortars Used in Full-Depth Precast Concrete Bridge Deck Panel Systems

Scholz, Donald P. 20 December 2004 (has links)
The use of full-depth precast concrete bridge deck panels is becoming more and more attractive to transportation authorities throughout the country. In comparison to conventional cast-in-place decks, precast decks are of higher quality, allow for the bridge to be opened to traffic in less time and are easier to maintain, rehabilitate, and replace. This ultimately results in lower costs for transportation authorities and less disruption for the motoring public. Unfortunately, the use of precast deck panel systems is hindered by the lack of design standardization and information regarding the performance of such systems. This research focuses on a key element of the system, the mortar or grout, which is used to connect the precast panels to the bridge girders by filling the space in the horizontal shear pockets and the haunches. Several essential mortar characteristics were identified and investigated in order to create a specification that indicates required performance criteria for mortars. This specification can be used to determine whether particular mortars or grouts are suitable for use in a full-depth precast concrete bridge deck panel system. / Master of Science
93

Une extension de la méthode mortar pour application aux contacts et au couplage de maillages / Extended mortar method for contact and mesh-tying applications

Akula, Basava Raju 04 February 2019 (has links)
Cette thèse a pour but de développer un ensemble de méthodes permettant de gérer les problèmes de contact et de couplage de maillages dans le cadre de la méthode des éléments finis classiques et étendus. Ces problèmes d'interfaces sont traités le long de surfaces réelles et virtuelles, dites “surfaces immergées”. Le premier objectif est d’élaborer une formulation de Mortar tridimensionnelle, efficace et parfaitement cohérente en utilisant la méthode du Lagrangien augmenté monolithique (ALM) pour traiter les problèmes de contact et de frottement. Cet objectif est réalisé dans le cadre de la méthode des éléments finis classique. Divers aspects du traitement numérique du contact sont discutés : la détection, la discrétisation, l’évaluation précise des intégrales de Mortar (projections, découpage, triangulation), la parallélisation du traitement sur des architectures parallèles à mémoire distribuée et l’optimisation de la convergence pour les problèmes impliquant à la fois le contact/frottement et les non-linéarités de comportement des matériaux. Grâce aux formulations de Mortar tirées des méthodes de décomposition de domaines, les problèmes de couplage de maillage pour la classe des interfaces non-compatibles sont également présentés.En outre, une nouvelle méthode numérique a été élaborée en 2D : nous la dénommons “MorteX”, car elle rassemble à la fois des fonctionnalités de la méthode Mortar et de la méthode X-FEM (méthode des éléments finis étendus). Dans ce cas, le couplage des maillages entre des domaines qui se chevauchent ainsi que le contact frottant entre des surfaces réelles d'un solide et certaines surfaces immergées au sein du maillage d'un autre corps peuvent être traités efficacement. Cependant, la gestion du couplage/contact entre des géométries non conformes à l'aide de surfaces immergées pose des problèmes de stabilité numérique. Nous avons donc proposé une technique de stabilisation qui consiste à introduire une interpolation des multiplicateurs de Lagrange à grains grossiers. Cette technique a été testée avec succès sur des “patch-tests” classiques et elle s'est également avérée utile pour les méthodes Mortar classiques, ce qui est illustré par plusieurs exemples pratiques.La méthode MorteX est aussi utilisée pour traiter des problèmes d’usure en fretting. Dans ce cas, l’évolution des surfaces de contact qui résulte de l’enlèvement de matière dû à l’usure est modélisée comme une évolution de surface virtuelle qui se propage au sein du maillage existant. L’utilisation de la méthode MorteX élimine donc le besoin de recourir aux techniques complexes de remaillage. Les méthodes proposées sont développées et implémentées dans le logiciel éléments finis Z-set. De nombreux exemples numériques ont été considérés pour valider la mise en œuvre et démontrer la robustesse, la performance et la précision des méthodes Mortar et MorteX. / In this work we develop a set of methods to handle tying and contact problems along real and virtual (embedded) surfaces in the framework of the finite element method. The first objective is to elaborate an efficient and fully consistent three-dimensional mortar formulation using the monolithicaugmented Lagrangian method (ALM) to treat frictional contact problems. Variousaspects of the numerical treatment of contact are discussed: detection, discretization, accurate evaluation of mortar integrals (projections, clipping, triangulation), the parallelization on distributedmemory architectures and optimization of convergence for problems involving both contact and material non-linearities. With mortar methods being drawn from the domain decomposition methods, the mesh tying problems for the class on non-matching interfaces is also presented.A new two-dimensional MorteX framework, which combines features of the extended finite element method (X-FEM) and the classical mortar methods is elaborated. Within this framework, mesh tying between overlapping domains and contact between embedded (virtual) boundaries can be treated. However, in this setting, severe manifestation of mesh locking phenomenon can take place under specific problem settings both for tying and contact. Stabilization techniques such as automatic triangulation of blending elements and coarse-grained Lagrange multiplier spaces are proposed to overcome these adverse effects. In addition, the coarse graining of Lagrange multipliers was proven to be useful for classical mortar methods, which is illustrated with relevant numericalexamples.The MorteX framework is used to treat frictional wear problems. Within this framework the contact surface evolution as a result of material removal due to wear is modeled as an evolving virtual surface. Use of MorteX method circumvents the need for complex remeshing techniques to account for contact surface evolution. The proposed methods are developed and implemented in the in-house finite element suite Z-set. Numerous numerical examples are considered to validate the implementation and demonstrate the robustness, performance and accuracy of the proposed methods.
94

Avaliação da influência da técnica de execução no comportamento dos revestimentos de argamassa aplicados com projeção mecânica contínua. / The influence of different execution techniques on the behavior of cement based rendering applied with the wet sprayed method.

Zanelatto, Kátia Cristina 26 September 2012 (has links)
No Brasil, a quase totalidade dos edifícios habitacionais empregam revestimentos de argamassa em suas fachadas. Este revestimento vem passando por alterações significativas ao longo do tempo, dentre as quais se destaca a substituição do lançamento manual de argamassas pela projeção, por meio de equipamentos mecânicos, em especial a aplicação mecanizada contínua, com bombas helicoidais. Acredita-se que este sistema, por possibilitar o fluxo contínuo na etapa de aplicação e promover a diminuição da interferência das habilidades dos operários durante a execução, permite alcançar maior produtividade e melhorar a qualidade dos revestimentos, mas as diferentes técnicas de execução empregadas para a produção dos revestimentos de argamassa aplicados com projeção mecânica contínua ainda não foram avaliadas sistemicamente quanto à sua interferência no comportamento destes revestimentos. Sendo assim, o objetivo deste trabalho é avaliar a influência de algumas variáveis empregadas na execução dos revestimentos de fachada de argamassa aplicados com projeção mecânica contínua, no seu comportamento, mais especificamente na adesão inicial, fissuração e aderência. Estas variáveis foram selecionadas através de um levantamento bibliográfico e aplicadas a um estudo experimental, no qual foram executados vinte e sete painéis de revestimento, para verificação da influência das variáveis no comportamento destes revestimentos. Ao final, foram apresentados e avaliados os resultados obtidos, por meio de análises qualitativas (adesão inicial e fissuração) e quantitativas (no caso de resistência de aderência). Os resultados obtidos permitiram concluir que, apesar de haver um acréscimo significativo da resistência de aderência à tração com a projeção mecânica contínua da argamassa, em comparação à aplicação manual, o teor de água das argamassas, associado à condição de umidade do substrato e ao tempo entre demãos, e as técnicas de acabamento da superfície do revestimento podem influenciar significativamente o comportamento dos revestimentos, aumentando ou diminuindo a resistência de aderência. / In Brazil, almost all residential buildings make use of exterior cement-based rendering. This rendering has been going through significant changes over time, among which the substitution of hand application of the mortar by mechanical methods of application, in particular the wet spraying method using rotor type machines. It is believed that this system, by allowing the continuous flow in the application step and reducing user skill interference, promotes greater productivity and helps to increase the quality of the rendering, but the different execution techniques employed in its production still havent been systematically evaluated regarding their interference in the renderings behavior. Hence, the objective of this study is to evaluate the influence of some variables related to the execution techniques of exterior cement-based rendering applied with the wet spraying method using rotor type machines on their behavior, more specifically on initial bonding, cracking and adhesion. These variables were selected through bibliographic data gathering, and then applied to an experimental study on which twenty seven rendering panels were executed for the verification of the influence of the variables on their behavior. The results were presented and evaluated by qualitative (in the case of initial bond and cracking) and quantitative analyses (in the case of adhesion). The results obtained allowed to conclude that, despite a significant increase in adhesion with the mechanical projection of the mortar compared to manual application, the water content of the mortar, associated with substrate moisture condition and time between coatings, as well as the techniques of surface finishing of the coating may affect the rendering quality by increasing or decreasing the adhesion strengths.
95

Avalia??o da utiliza??o de residuo de vidro de garrafas na produ??o de argamassa

Lordelo, Rodrigo Seixas Dourado 16 July 2018 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2018-09-10T20:23:00Z No. of bitstreams: 1 AVALIA??O DA UTILIZA??O DE RES?DUO DE VIDRO DE GARRAFAS NA PRODU??O DE ARGAMASSA.pdf: 2101422 bytes, checksum: 3e30e4c6ad0b0e448d0f28282d5385fa (MD5) / Made available in DSpace on 2018-09-10T20:23:00Z (GMT). No. of bitstreams: 1 AVALIA??O DA UTILIZA??O DE RES?DUO DE VIDRO DE GARRAFAS NA PRODU??O DE ARGAMASSA.pdf: 2101422 bytes, checksum: 3e30e4c6ad0b0e448d0f28282d5385fa (MD5) Previous issue date: 2018-07-16 / The use of waste incorporated in building materials has been pointed out as an alternative for more adequate disposal of solid waste. Among the wastes generated in Brazil, are the glass. Less than half of the glass bottles produced in Brazil are recycled. In the present work the influence of the use of waste glass of brown bottles, crushed, as partial substitute of the natural sand, in the production of mortars was evaluated. The substitution contents evaluated were 10, 20 and 30%, by mass, in addition to the reference mortar (without waste glass). The properties of the mortars in the fresh state were evaluated (workability, specific mass and incorporated air content) and also in the hardened state (flexural tensile strength, compressive strength, water absorption, void index, specific mass and alkali-silica reactivity). The results of the tests indicated that the use of waste glass bottles, replacing the natural aggregate, did not alter the fluidity of the mortars, but decreased the density and increased the content of incorporated air. The incorporation of the waste provided an increase in the tensile strengths in flexion and compression, in relation to the reference mortar. With respect to the possible alkali-silica reactivity, it was verified that the mortars with the waste glass bottle did not exceed the expansion limit established in accordance with NBR 15577-4 (ABNT, 2009). Based on the results it was concluded that it is possible to use up to 30% of waste glass of brown bottles, replacing the natural sand. / A utiliza??o de res?duos incorporados ? materiais de constru??o vem sendo apontada como uma alternativa para destina??o mais adequada dos res?duos s?lidos. Dentre os res?duos gerados no Brasil, est?o os de vidro. Menos da metade das embalagens de vidro produzidas no Brasil s?o recicladas. No presente trabalho foi avaliado a influ?ncia da utiliza??o de res?duo de vidro de garrafas de cor marrom, triturado, como substituto parcial do agregado mi?do natural, na produ??o de argamassas. Os teores de substitui??o avaliados foram de 10, 20 e 30%, em massa, al?m da argamassa de refer?ncia (sem res?duo). Foram analisadas propriedades das argamassas no estado fresco (trabalhabilidade, massa espec?fica e teor de ar incorporado) e no estado endurecido (resist?ncia ? tra??o na flex?o, resist?ncia ? compress?o, absor??o de ?gua, ?ndice de vazios, massa espec?fica e reatividade ?lcali-s?lica). Os resultados dos ensaios indicaram que o uso de res?duo de vidro de garrafa, em substitui??o ao agregado natural, n?o alterou a fluidez das argamassas, mas diminuiu a densidade e aumentou o teor de ar incorporado. A incorpora??o do res?duo proporcionou aumento nas resist?ncias ? tra??o na flex?o e ? compress?o, comparado ? argamassa de refer?ncia. Com rela??o ? poss?vel reatividade ?lcali-s?lica, verificou-se que as argamassas com o res?duo de vidro de garrafa n?o excederam o limite de expans?o estabelecido conforme a NBR 15577-4 (ABNT, 2009). Com base nos resultados concluiu-se que ? poss?vel utilizar at? 30% de res?duo de garrafa de vidro de cor marrom, em substitui??o ao agregado natural.
96

Estruturas tipo sanduíche com placas de argamassa projetada / Sandwich-type structures with plates made of projected mortar

Bertini, Alexandre Araújo 22 February 2002 (has links)
Elementos tipo sanduíche, com placas de argamassa projetada, têm sido utilizados na construção de edificações em alguns países, inclusive no Brasil, apresentando boas características de resistência mecânica, térmica e acústica. De maneira geral, a aplicação desse tipo de elemento tem se restringido a obras de edificações, sendo utilizado principalmente como painéis de fechamento, portantes ou não, existindo ainda um potencial a ser explorado em obras de infra-estrutura, tais como: muros de arrimo, canais, galerias e reservatórios de água. Apesar de ser um método utilizado na construção de edificações, existem dúvidas, tais como: resistência efetiva da argamassa projetada, colaboração entre as placas resistentes em função do tipo de núcleo, modo de combater os efeitos de retração da argamassa, etc. Apresenta-se neste trabalho um estudo sobre a resistência efetiva da argamassa projetada, no qual se obteve que a sua resistência é de aproximadamente 80% da resistência à compressão de corpos-de-prova cilíndricos. Realizaram-se ainda ensaios para analisar a ligação entre elementos tipo sanduíche e seu comportamento à flexão, que comprovam o bom desempenho estrutural. Acredita-se que essa técnica de construção sanduíche possa ser aplicada em obras de infra-estrutura de interesse social, trazendo vantagens tecnológicas e econômicas em relação a sistemas tradicionais / Sandwich–type elements, with plates made of projected mortar, have been used in the construction of buildings in some countries, including Brazil, showing expressive thermical, acoustical and mechanical strength characteristics. In general, the application of this kind of element have been limited to buildings, mainly used as cladding panels, with carrying load capacity or not, and have other potential uses in infra-structural works to be explored such as bearing walls, channels, and water reservoirs. Although it is a method that have been conventionally applied in the construction of buildings, there are uncertainties in some parameters, like the effective strength of the projected mortar, interaction between the plates related to the type of core, the mode against shrinkage of the mortar etc. It is showed in this work a study concerning the effective strength of the projected mortar. As a result of a series of tests in walls made of projected mortar, it is determined that the effective strength of the projected mortar is 80% of that one measured from cylindrical specimens in compression tests. As well, some tests have been executed to analise the bending behaviour and the connections between the plates of the sandwich-type specimens, which demonstrated a relatively high structural performance. It is believed that this technical solution can be well applied to public works of social interest, and can offer technological and economical advantages in contrast to the traditional systems
97

Artilleribataljonen och vapenanskaffning : taktiskt eller organisatoriskt rationellt? / Artillery battalion and weapons acquisition : tactic or bureaucratic rational?

Samuelsson, Emil January 2010 (has links)
<p>Försvarsmakten har förändrats från ett invasionsförsvar till ett insatsförsvar. Det har inneburit nedläggningar och omstruktureringar av organisationer. Artilleriet är en av de vapenslag som har gått från flertal regementen till idag ett regemente. Artilleribataljonen som är artilleriets insatsförband har kännetecknas som ett förband med lång räckvidd och kraftig verkan. Med pjäser som har kaliber 15,5cm understödjer de manöverförbanden. Idag har artilleribataljonen 8cm granatkastare som sekundär beväpning, ett vapen som har dålig räckvidd jämfört med 15,5cm pjäser, ett vapen som inte kan bekämpa pansar mål eller precisionsbekämpa. Detta arbete är en studie om varför artilleribataljonen anskaffat 8cm granatkastare. Är det av taktiskt rationella anledningar eller är det organisatoriskt rationella anledningar? Arbetet utgår från två hypoteser som förklarar varför artilleribataljonen anskaffat 8cm granatkastare. Studien visar på att artilleribataljonen utökar sina uppgifter genom att anskaffa 8cm grankastare. Det gör att artilleribataljonen har teoretiska möjligheter att konkurrera om platser vid eventuella missioner eller en platsvid Nordic battlegroup. Studien analyserar även artilleribataljonens uppgifter, dessa uppgifter skall organisationen klara av. Enligt resultatet har artilleribataljonen inte de förutsättningarna att lösa alla uppgifter utan 8cm granatkastare. Därför är det taktiskt rationellt att anskaffa 8cm granatkastare som sekundär beväpning.</p> / <p>The Swedish armed force has changed from defending the country from invasions to a military force that can be used as a military intervention at different places around the world. This change has meant that some organizations has been discontinued and reorganized. The artillery is one of the branches of the fighting services who have gone from several regiments to only one. The artillery battalion is recognized as a unit that has a long range and powerful impact. With 15,5 guns they support the maneuver units. Today the artillery battalion have 8cm mortars as secondary armament, a weapon that has bad range compared to 15,5 guns and a weapon that can’t penetrate armored targets and has bad accuracy. This essay is a study about why the artillery battalion has acquired 8 cm mortars. Is it because of tactical rational reasons or is it because of organizational rational reasons? The essay takes stand from two hypotheses that explain why the artillery battalion has acquired 8 cm mortars. The study indicates that the artillery battalion increases their assignments by acquiring 8 cm mortars. This enables the battalion theoretical possibilities to compete for places in missions or places in the Nordic battlegroup. The study also analyses the artillery battalion’s tasks, tasks that the organization should manage. The artillery battalion has, according to the result, not the resources to solve all the assignments without the 8 cm mortars. Therefore it is tactical rationally to acquire 8 cm mortars assecondary armament.</p>
98

Artilleribataljonen och vapenanskaffning : taktiskt eller organisatoriskt rationellt? / Artillery battalion and weapons acquisition : tactic or bureaucratic rational?

Samuelsson, Emil January 2010 (has links)
Försvarsmakten har förändrats från ett invasionsförsvar till ett insatsförsvar. Det har inneburit nedläggningar och omstruktureringar av organisationer. Artilleriet är en av de vapenslag som har gått från flertal regementen till idag ett regemente. Artilleribataljonen som är artilleriets insatsförband har kännetecknas som ett förband med lång räckvidd och kraftig verkan. Med pjäser som har kaliber 15,5cm understödjer de manöverförbanden. Idag har artilleribataljonen 8cm granatkastare som sekundär beväpning, ett vapen som har dålig räckvidd jämfört med 15,5cm pjäser, ett vapen som inte kan bekämpa pansar mål eller precisionsbekämpa. Detta arbete är en studie om varför artilleribataljonen anskaffat 8cm granatkastare. Är det av taktiskt rationella anledningar eller är det organisatoriskt rationella anledningar? Arbetet utgår från två hypoteser som förklarar varför artilleribataljonen anskaffat 8cm granatkastare. Studien visar på att artilleribataljonen utökar sina uppgifter genom att anskaffa 8cm grankastare. Det gör att artilleribataljonen har teoretiska möjligheter att konkurrera om platser vid eventuella missioner eller en platsvid Nordic battlegroup. Studien analyserar även artilleribataljonens uppgifter, dessa uppgifter skall organisationen klara av. Enligt resultatet har artilleribataljonen inte de förutsättningarna att lösa alla uppgifter utan 8cm granatkastare. Därför är det taktiskt rationellt att anskaffa 8cm granatkastare som sekundär beväpning. / The Swedish armed force has changed from defending the country from invasions to a military force that can be used as a military intervention at different places around the world. This change has meant that some organizations has been discontinued and reorganized. The artillery is one of the branches of the fighting services who have gone from several regiments to only one. The artillery battalion is recognized as a unit that has a long range and powerful impact. With 15,5 guns they support the maneuver units. Today the artillery battalion have 8cm mortars as secondary armament, a weapon that has bad range compared to 15,5 guns and a weapon that can’t penetrate armored targets and has bad accuracy. This essay is a study about why the artillery battalion has acquired 8 cm mortars. Is it because of tactical rational reasons or is it because of organizational rational reasons? The essay takes stand from two hypotheses that explain why the artillery battalion has acquired 8 cm mortars. The study indicates that the artillery battalion increases their assignments by acquiring 8 cm mortars. This enables the battalion theoretical possibilities to compete for places in missions or places in the Nordic battlegroup. The study also analyses the artillery battalion’s tasks, tasks that the organization should manage. The artillery battalion has, according to the result, not the resources to solve all the assignments without the 8 cm mortars. Therefore it is tactical rationally to acquire 8 cm mortars assecondary armament.
99

The Transitional Environment of E-tail vs. Retail : An exploratory study of the factors that trigger channel purchasing decisions within the area of Umeå

May, Spencer, Sundberg, Lars Andreas January 2013 (has links)
In the field of consumer goods the ecommerce industry has been growing rapidly. This rapid growth has created significant pressure on traditional retailers forcing them to institute change or risk being removed from the market. The primary objective of this study was to examine the shopping behavior of Umeå inhabitants in the Retail vs. Online Channels of the clothing sector. The goal was to identify key decision factors that cause consumers to choose a specific purchasing channel and use this information to create and test a conceptual model. The model focused on five decision factors including: (1) Loyalty (online, retail), (2) Physical Product, (3) Price, (4) Promotion, and (5) Convenience. We were also were interested in whether IT affinity (level of Internet browsing experience) had a direct relationship to the decision factors. To satisfy our research objective a deductive quantitative method was chosen. Information was tested in the form of a self-completion survey using a sample taken from 113 Umeå, Sweden residents between the ages of 18-29. This age group was specifically chosen, as almost 90% made purchases within a 4-month period (HUI, 2012 p.6). In the final analysis we concluded that all five decision factors in the Online Channel correlated whether positively or negatively, i.e., in some manner affected the final purchasing decision. The decision factors Loyalty Online, Promotion, and Physical Product were the strongest factors influencing the decision to purchase online. Price and IT Affinity correlated with Convenience, which in turn, correlated with Promotion, a decision factor contributing to online purchasing. Physical Product negatively correlated. Regarding the Retail Channel, the Physical Product was the strongest and only significant decision factor correlating positively to retail purchasing. With this understanding we conclude to a certain extent that consumers with a strong desire to try a physical product need other motivational factors to change channels toward online purchasing. Research on a larger scale would provide additional insight in this rapidly growing and interesting market.
100

Aderência de revestimentos de argamassa em substrato de concreto : influência da forma de aplicação e composição do chapisco / Mortar rendering bond in concrete substrate: influence of the application form and composition of slurry mortar

Gasperin, Josiane January 2011 (has links)
Revestimentos de argamassa, embora largamente utilizados, ainda e cada vez mais, geram interesse, tanto por parte do meio acadêmico quanto pelas empresas construtoras. Este fato se deve pela, sempre presente, necessidade de melhoria da tecnologia, visando, principalmente, maior conhecimento dos elementos constituintes do sistema de revestimento e, também, devido ao grande número de manifestações patológicas ocorridas neste tipo de revestimento, em especial o descolamento. Neste contexto, este trabalho teve como objetivo avaliar a influência da camada de preparo da base, o chapisco, quanto a sua forma de aplicação e composição, na resistência de aderência de revestimentos de argamassa aplicados sobre substrato de concreto de baixa porosidade. Para isso, foram moldadas placas de concreto com dimensões de (35x25x5)cm e resistência, aos 28 dias de, aproximadamente, 30MPa, que receberam argamassa de chapisco e posteriormente foram revestidos com argamassa de revestimento. Afim de isolar o efeito do chapisco, nesta pesquisa, o substrato de concreto e a argamassa de revestimento foram mantidos fixos, sendo, então, o chapisco o único elemento variável do sistema. Em relação ao chapisco variou-se sua forma de aplicação (manual e mecanizada), sua composição, onde foi analisada a mudança de granulometria (uma contínua e bem graduada e uma descontínua e mal graduada), a introdução de sílica ativa e de aditivo retentor de água. O substrato de concreto teve cura submersa em água e cal, durante 28 dias, e a argamassa de chapisco e a argamassa de revestimento foram curadas à temperatura de 23±2°C e umidade relativa do ar de 60±10% por 3 e 28 dias, respectivamente. Após 59 dias do início da moldagem, o conjunto “substrato+chapisco+argamassa de revestimento” foi submetido aos ensaios de resistência de aderência à tração e ao cisalhamento. A partir dos resultados obtidos é possível afirmar que quanto a forma de aplicação, a aplicação mecanizada utilizada, de recipiente acoplado, a canequinha, não gerou resultados satisfatórios, uma vez que para as características da argamassa de chapisco utilizada, sendo está de alta relação água/cimento, a aplicação resultou em uma camada desuniforme, mostrando que aplicação manual, mesmo rústica, para chapiscos ainda é a melhor escolha. Quanto a composição do chapisco, os melhores resultados obtidos para a resistência de aderência foram obtidos com chapiscos confeccionados com areia de granulometria contínua e bem graduada. A introdução da sílica no chapisco mostrou uma tendência de melhora para a resistência de aderência à tração e uma melhoria significativa, comprovada por análise estatística, na resistência ao cisalhamento e a introdução de aditivo retentor de água, promoveu uma melhora significativa na resistência de aderência à tração e uma tendência de melhora na resistência de aderência ao cisalhamento. / Although widely used, mortar wall coverings still generate interest by both academia and construction companies. This fact is caused by the ever-present need for improved technology, having as principal objective the more refined knowledge about the constituents of the coating system and also the large number of pathologies occurring in this type of siding, in particular its detachment. In this context, this study had the objective of analizing the influence of the application form and composition of slurry mortar on the bonding strength of coatings applied over concrete substrate. For this, concrete plates of 35x25x5cm were molded, with compressive strength at 28 days of, approximately, 30MPa. After that, the plates were coated with coating mortar and slurry mortar. In order to isolate the effect of slurry mortar in this research, the concrete substrate and mortar coating were kept fixed, and the slurry mortar is the only variable element of the system. It was varied the form of application (manual and mechanized), the composition, where were analyzed the change of sand granulometry (a continuous and well-graded, a discontinuous and bad-graded), the introduction of silica and water retaining additive. The concrete substrate was curing in water and lime for 28 days, and mortar coating and slurry mortar were cured at 23±2°C and relative humidity of 60±10%, for 3 and 28 days, respectively. After 59 days from the start of the molding of concrete plates, the "substrate+slurry mortar+mortar coating" samples were subjected to tests of tensile bond strength and shear. From the results obtained, were is can be said that the mechanized application form used did not generate satisfactory results, possibly due to high water/cement ratio of the slurry mortar used, resulting in an uneven layer, showing that manual application, even rustic, for slurry mortar is still the best choice. For the composition of slurry mortar, the best results for bond strength were obtained with slurry mortars made with well-graded sand with a continuous granulometric. The introduction of silica in the slurry mortar showed a tendency to increase the tensile bond strength and a significant increase, proven by statistical analysis, in shear bond strength. The introduction of water retaining additive, a significant improvement in tensile bond strength and a tendency to increase the shear bond strength.

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