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Factors Affecting the Structural Integrity of Wood-Based Composites: Elevated Temperature and Adhesive BondingLi, Yuqin 01 April 2021 (has links)
This study focuses on factors that affect the structural integrity of wood-based composites. Wood-based composites exposed to fire may decompose due to the elevated temperatures, resulting in a degradation in performance. Thermal modelling can only predict the structural integrity of construction materials in fire if it is given accurate inputs. Consequently, methods for the characterization of the thermal, physical, and mechanical behaviors of wood and wood-based composites are selected, designed, and benchmarked. The relevant thermal and physical responses characterized includes porosity, permeability and thermal diffusivity. Common construction materials (white pine board, medium density fiberboard and spruce 24) are characterized from room temperature to complete decomposition. The characterization techniques and processes are based on existing literature and relevant ASTM standards. To reduce the number of experiments required for future material characterization, estimates based upon the degree of decomposition and the measured values for the virgin and charred materials are used. For porosity and thermal diffusivity, these models allow values at intermediate temperatures to be estimated with measurements at room temperature and complete decomposition and thermogravimetric analysis (TGA). We find that permeability depends heavily on the microstructure of materials and should be measured independently at the conditions of interest.
An additional important aspect of the performance of wood-based composites is the fracture behavior of wood/adhesive systems. Adhesive bonding enables many engineered wood products such as furniture and structural wood joints and the adhesive fracture toughness often determines the durability. The conventional characterization method for wood/adhesive fracture resistance relies on samples with machined grain angles designed to funnel cracks to the adhesive interface. This method of sample preparation is difficult and time-consuming for certain wood species. In this work, a practical and efficient method is developed to characterize adhesive fracture energy of adhesively bonded veneer systems. In the method, auxiliary aluminum adherends are bonded to the veneers in an effort to drive the crack to the wood/adhesive interface. The method is applied to rotary-peeled veneers and saw-cut veneers produced from three species of wood bonded with three commonly used adhesives. The new tests method yields a high interfacial failure rate and successfully identifies differences in the performance of the three adhesives. SPG (one species of the rotary-peeled veneers) demonstrates a rising R-curve behavior (an increase in the fracture toughness with crack length) when bonded on the loose side. This increase in fracture toughness is observed to be a result of adhesive-substrate interaction, which is a developing process zone behind the crack tip consisting of bridged wood ligaments. / Doctor of Philosophy / Construction materials exposed to elevated temperatures from fires may reach temperatures where the material decomposes from the original material to a char. Protected and unprotected structural timber products exposed to fires may exhibit this behavior resulting in a degradation of performance. Understanding the thermal and physical responses of these materials is crucial in evaluating the materials behavior in fire. Additionally, many wood-based products (such as furniture) rely on adhesive bonds. Consequently, their usefulness is determined by the performance of those bonds. In this work, methods are developed to measure key properties impacting the behavior of wood-based systems at elevated temperatures, such as that experienced in fires and when they are subjected to forces attempting to debond one wood material from another. These techniques are demonstrated on common building materials (white pine board, medium density fiberboard and spruce 24) and wood veneers from three different species bonded with three different adhesives. Mathematical models are developed to expand the use of the data beyond the specific conditions for which it is measured.
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Avaliação das propriedades físicas de resinas compostas restauradoras pré-aquecidas e resinas fluidas com a finalidade de cimentação de facetas cerâmicas / Evaluation of the physical properties of preheated restorative resin composites and fluid resins for ceramic veneer cementationAlmeida, Sandra Barbosa Moraes de 07 December 2016 (has links)
Este estudo teve o objetivo de avaliar as propriedades físicas de resinas compostas restauradoras pré-aquecidas e de resinas fluidas com finalidade de cimentação de facetas de cerâmicas em comparação aos cimentos resinosos. Foram produzidos corpos de prova de duas marcas comerciais 3M ESPE e Ivoclar Vivadent, sendo: duas resinas restauradoras (Filtek Z250XT e Tetric N Ceram) nas condições: temperatura ambiente (RZ e RT), aquecidas à 45°C (RZ45 e RT45), aquecidas à 60°C (RZ60 e RT60); duas resinas fluidas (Filtek Z350 Flow e Tetric N Flow) denominadas FZ e FT e dois cimentos resinosos (Relyx Veneer e Variolink N) denominados CR e CV. Os grupos experimentais foram avaliados quanto à espessura de película por duas metodologias, resistência à flexão biaxial (RFB) e módulo de elasticidade (ME) executados em máquina de ensaio universal (modelo 5565, Instron Corp, Canton MA, EUA), microdureza Knoop feitas em microdurômetro (Shimadzu HMV-2, Tóquio, Japão) e diferença de cor (?E), razão de contraste e opalescência realizadas no espectrofotômetro CM-3770 (Konica Minolta, Japão). Os dados foram avaliados por análise de variância e teste de Tukey (p<0,05). As resinas restauradoras apresentaram películas com espessura maiores que 100 ?m, enquanto as resinas fluidas e os cimentos resinosos apresentaram valores menores que 50 ?m. Os grupos experimentais RZ, RZ45 e RZ60 apresentaram os maiores valores de KHN, RFB e ME. Os grupos RT, RT45, RT60, FT, CV e CR apresentaram os menores valores de RFB e semelhantes entre si. Para a KHN, os grupos RT, RT45, RT60, FZ e CR apresentaram valores intermediários e semelhantes entre si, e superiores aos grupos FT e CV. Os resultados de ?E mostraram valores acima de 2 para todos os grupos experimentais, com exceção do RZ60. Os maiores valores de ?E foram evidenciados nos grupos RT45 e RT60. A razão de contraste foi estatisticamente menor para o grupo CV e os maiores valores de opacidade foram encontrados nos grupos RZ, RZ45 e FZ. A opalescência foi superior nos grupos FZ, CR, FT e CV. Considerando as limitações do presente estudo, concluiu-se que os tratamentos térmicos não alteraram as propriedades mecânicas das resinas restauradoras e não promoveram uma redução da espessura de película que atenda aos requisitos da ISO4049. As resinas fluidas e os cimentos apresentaram espessura de película inferior à 50?m e propriedades mecânicas que atendem à normativa ISO4049. A opalescência maior foi encontrada nos cimentos resinosos e a diferença de cor e razão de contraste apresentaram resposta grupo dependente. / The objectives of this study were to evaluate the physical properties of preheated restorative resin composites and fluid resins with the purpose of cementation of ceramic veneers in comparison to resin cements. Specimens were prepared with two restorative resin composites (Filtek Z250XT and Tetric N Ceram), in the following conditions: room temperature (RZ; RT), heated at 45°C (RZ45; RT45), and heated at 60°C (RZ60; RT60). Two flowable resins (Filtek Z350 Flow and Tetric N Flow) named FZ and FT and two resin cements (Relyx Veneer and Variolink N), called CR and CV, were also used. The experimental groups were evaluated in regards to film thickness with two methodologies; biaxial flexure strength (BFS) and modulus of elasticity (ME) (model 5565, Instron Corp, Canton MA, USA); Knoop microhardness test (KMT) (Shimadzu HMV-2, Tokyo, Japan), color difference (?E), contrast ratio and opalescence test (CM-3770d, Konica Minolta, Japan). Data were assessed by ANOVA and a post-hoc Tukey test (p<0.05). The restorative resins presented film thickness larger than 50?m, whereas the flowable resins and resin cements showed inferior values. The experimental groups RZ, RZ45 and RZ60, revealed greater values of KHN, BFS and ME. The RT, RT45, RT60, FT, CV and CR groups showed lower values for BFS and similar to each other. For KHN the RT, RT45, RT60, FZ and CR groups exposed intermediate and similar values to each other, and superior values to FT and CV groups. Color difference (?E) results demonstrated results superior than 2 for all experimental groups, with the exception of RZ60 group. The greater values of ?E were shown in RT45 and RT60 groups. Contrast ratio was statistically lower for the CV group and the highest values of opacity were verified in RZ, RZ45 and FZ groups. Opalescence was superior in FZ, CR, FT and CV groups. Considering the limitations of this study, the results demonstrated that preheated treatments did not modify the mechanical properties of restorative resin composites and didn\'t reduce film thickness which attend to ISO4049 parameters. Flowable resins and cements obtained film thickness inferior to 50?m and biaxial flexure strength results that are presented by the ISO4049. The greater opalescence was shown in the resin cements, also color difference and contrast ratio revealed results that were group dependent.
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Can laser cutting be an alternative technique for marquetry completion in furniture conservation? / Kan laserskuren intarsia vara en alternativ teknik för komplettering i möbelkonservering?Jover Casanovas, Elena January 2011 (has links)
This study describes experiments and findings of an investigation to evaluate the use of laser cutting as an alternative to traditional sawing techniques in marquetry completion conservation. Experiments on veneer from 11 different species of wood, covering ring porous, semi-diffuse/-ring porous and diffuse porous woods, were carried out and examined. The optimal cutting metrics with respect to speed, power and frequency for the types of wood were determined. The most important ethical question for a conservator is to be able to preserve as much as original material as possible. The results of this project show that the use of a laser cutting machine is indeed a suitable solution to produce replacement veneer for marquetry works in furniture conservation with respect to quality and time. Especially when it comes to the precision in the shape of the replacement piece, laser cutting is superior to hand sawing. This makes laser cutting an interesting option and reduces the need for expert skills in hand sawing in order to perform very detailed completion work. It also reduces the need of invasive work on the original marquetry to accommodate the replacement piece. The findings are general for all of the examined types of wood. On the negative side, the laser cutting machine requires a relatively big initial investment, making it difficult to say if it is really a cost-effective method of cutting replacement veneer pieces. / Syftet med projektet är att hitta en alternativ metod för att producera kompletteringsbitar av fanér till gamla intarsiaobjekt. En lämplig metod ska vara tids- och kostnadseffektiv, hållbar och reversibel. Laserskärning innebär stora möjligheter att kraftigt reducera tid och kostnad vid komplettering av intarsia, vilket möjliggör för flera möbelägare att låta utföra en professionell konservering av sina historiska objekt.
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Überlebens- und Erfolgsrate von Keramik-Veneers nach 3 Jahren Tragezeit / Survival- and success rate of ceramic veneer restorations after 3 yearsSpellmann, Julian 12 December 2011 (has links)
No description available.
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CARACTERÍSTICAS FÍSICO-MECÂNICAS DE PAINÉIS DE LÂMINAS PARALELAS REFORÇADOS COM FIBRA DE VIDRO / PHYSICAL AND MECHANICAL CHARACTERISTICS OF LAMINATED VENEER LUMBER REINFORCED WITH FIBERGLASSBuligon, Ediane Andreia 18 July 2011 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The aim of the present research was to evaluate the physical and mechanical properties of
LVL reinforced with fiberglass with two types of resins. Pinus elliottii veneers with 1,5 mm
thickness were used to manufacture of the LVL panels. The panels were manufactured in two
steps. The first one was the assembling of the LVL panels with nine layers of wood veneer
glued with phenol-formaldehyde resin. The second step consisted into reinforcing the LVL
with fiberglass impregnated with epoxy resin (E) or isophthalic resin (I). The treatments
were: panels without reinforcement (T), panels reinforced with one fiberglass layer (E T1 e
I T1), panels reinforced with two fiberglass layers (E T2 e I T2) and panels reinforced
with four fiberglass layers (E T3 e I T3). The size of panel was 45 cm x 34 cm x 1,08 cm.
The physical properties tested were density and moisture content. The mechanical properties
tested were: static bending in flatwise and edgewise position, modulus of elasticity (MOE)
and modulus of rupture (MOR); glueline shear strength by compression loading; hardness
test; and non-destructive test by ultrasound method. The epoxy and the isophthalic resin
showed similar mechanical performance among the different treatments.The resistence and
stiffness of the panels were influenced by the reinforcement. The MOE in flatwise position
was influenced by one reinforcement layer and the MOR was influenced by two
reinforcement layers. In the edgewise position the MOE and the MOR values remained
constant among the treatments with two fiberglass reinforcement layers. The MOE in nondestructive
test had higher values when compared with the destructive method, however these
values remained stable with two layers of reinforcement. Two layers of reinforcement on the
tensile and compression side had higher values in hardness test. The epoxy resin presented
higher glueline resistence and higher percentage of wood failure. Isophthalic and phenolic
resin presented similar values of glueline strenght, however the isophthalic resin had lower
percentage of wood failure. Thus, the reinforcement with one layer of fiberglass imprenated
with epoxy resin on the tensile side would be enough to promote the mechanical qualities of
LVL. / O objetivo desta pesquisa foi avaliar as propriedades físico-mecânicas de painéis de lâminas
paralelas (LVL) reforçadas com camadas de fibra de vidro inpregnadas com dois tipos de
matrizes. Lâminas de madeira de Pinus ellliottii com espessura de 1,5 mm foram utilizadas na
fabricação dos painéis. A montagem dos painéis foi realizada em duas etapas. A primeira
consistiu na fabricação dos painéis LVL com nove camadas de lâminas de madeira unidas
com resina à base de fenol-formaldeído na gramatura de 190 g/m2 em linha simples. E a
segunda etapa consistiu na aplicação do reforço de fibra de vidro impregnado com resinas
epóxi (E) ou poliéster isoftálica com NPG (I). Os tratamentos utilizados foram: painéis sem
reforços (T), painéis com uma camada de fibra de vidro (E T1 e I T1), painéis com duas
camadas de fibra de vidro, sendo uma camada no lado de compressão e uma camada no lado
de tração (E T2 e I T2) e painéis com quatro camadas de fibra de vidro, duas camadas do
lado de compressão e duas camadas no lado de tração separados por uma lâmina de madeira
(E T3 e I T3). Foram realizadas três repetições por tratamento, totalizando 21 painéis. As
dimensões finais dos painéis foram 45 cm x 34 cm x 1,08 cm. Para determinar a qualidade
dos painéis LVL foram avaliadas as propriedades físicas (massa específica e teor de umidade)
e a resistência mecânica (flexão estática na posição flatwise e egdewise, resistência ao
cisalhamento, dureza Janka e teste não destrutivo utilizando ultrassom). A resina epóxi e a
resina isoftálica apresentaram as mesmas qualidades mecânicas nos diferentes tratamentos. A
aplicação do reforço influenciou na resistência e na rigidez do painel. Na flexão estática na
posição flatwise o módulo de elasticidade (MOE) foi influenciado por uma camada de reforço
e o módulo de ruptura (MOR) por duas camadas de reforço. Na posição edgewise os valores
de MOE e do MOR se mantiveram estáveis com a aplicação de duas camadas de reforços de
fibra de vidro. O MOE pelo método ultrassônico apresentou valores maiores quando
comparado com o método estático; em ambos os métodos os valores mantiveram-se estáveis
com a aplicação de duas camadas de reforço. A dureza Janka foi maior para as painéis com
mais camadas de fibra de vidro na posição de tração e compressão. A resina epóxi apresentou
maior resistência ao cisalhamento e maior percentual de falhas na madeira, enquanto que a
resina isoftálica, apesar de apresentar valores de resistência similares à fenólica, não
apresentou boa adesão à madeira, representada pelo baixo percentual de falhas na madeira. A
aplicação de uma camada de reforço de fibra de vidro com resina epóxi na posição de tração
seria o suficiente para melhorar as qualidades mecânicas dos painéis LVL fabricados com
lâminas de madeira de pinus unidas com fenol-formaldeído.
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Proposta metodológica para o projeto de sistemas de fechamento em alvenaria para edifícios institucionais em estrutura de aço / Methodological proposal for the design of masonry veneer systems in institutional buildings with steel structure.Araújo, André Luís de 13 August 2010 (has links)
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Previous issue date: 2010-08-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The durability performance of multi storey buildings of steel structure is closely
associated to the executive project planning in order to provide systems which are
exposed to external conditions. The aim of this research was to present a
methodological proposal for the design of masonry veneer systems for steel structure of institutional buildings which present high performance regarding durability. In order to
execute this proposal, the performance of the veneer system of four institutional
buildings at UFV campus was evaluated through building pathologies examination.
Buildings which presented variations on the type of connections between masonry and
structure, the type of masonry veneer and the type of façades finishes were surveyed.
Then, the designed information was confronted with the construction method applied
for the masonry veneer details. The confrontation was used to develop sequential
procedures to assist the development of a masonry veneer design which aims to prevent pathologies in steel structure. Finally, two building projects were developed using the proposed methodology in a practical design process. / O desempenho de edifícios quanto à durabilidade está relacionado com a
previsibilidade dos projetos executivos em planejar sistemas com vistas à condição de exposição ambiental a qual os mesmos estarão submetidos. O objetivo deste trabalho foi desenvolver uma proposta metodológica para o projeto de sistemas de fechamento em alvenaria para edifícios institucionais com estrutura de aço, que proporcione um bom desempenho quanto à durabilidade da estrutura e do fechamento. Para subsidiar esta proposta metodológica, avaliou-se o desempenho dos sistemas de fechamento de quatro edifícios institucionais construídos no Campus de Viçosa da Universidade Federal de Viçosa por meio da vistoria técnica de suas manifestações patológicas. Buscaram-se edifícios que apresentassem variações no tipo de fechamento, no tipo de ligações alvenaria-estrutura e no tratamento dado às fachadas. Avaliaram-se as informações de projeto destes edifícios e a eficácia dos detalhes arquitetônicos produzidos. Com base nestas informações, determinou-se a qualidade das práticas de projeto e produziu-se uma seqüência de procedimentos para o desenvolvimento de projetos de sistema de
fechamento em alvenaria com vistas à prevenção do surgimento de manifestações
patológicas. Para fins de teste demonstrou-se, por meio de dois casos de projetos de
sistemas de fechamento, a aplicação desta proposta metodológica.
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Avaliação das propriedades físicas de resinas compostas restauradoras pré-aquecidas e resinas fluidas com a finalidade de cimentação de facetas cerâmicas / Evaluation of the physical properties of preheated restorative resin composites and fluid resins for ceramic veneer cementationSandra Barbosa Moraes de Almeida 07 December 2016 (has links)
Este estudo teve o objetivo de avaliar as propriedades físicas de resinas compostas restauradoras pré-aquecidas e de resinas fluidas com finalidade de cimentação de facetas de cerâmicas em comparação aos cimentos resinosos. Foram produzidos corpos de prova de duas marcas comerciais 3M ESPE e Ivoclar Vivadent, sendo: duas resinas restauradoras (Filtek Z250XT e Tetric N Ceram) nas condições: temperatura ambiente (RZ e RT), aquecidas à 45°C (RZ45 e RT45), aquecidas à 60°C (RZ60 e RT60); duas resinas fluidas (Filtek Z350 Flow e Tetric N Flow) denominadas FZ e FT e dois cimentos resinosos (Relyx Veneer e Variolink N) denominados CR e CV. Os grupos experimentais foram avaliados quanto à espessura de película por duas metodologias, resistência à flexão biaxial (RFB) e módulo de elasticidade (ME) executados em máquina de ensaio universal (modelo 5565, Instron Corp, Canton MA, EUA), microdureza Knoop feitas em microdurômetro (Shimadzu HMV-2, Tóquio, Japão) e diferença de cor (?E), razão de contraste e opalescência realizadas no espectrofotômetro CM-3770 (Konica Minolta, Japão). Os dados foram avaliados por análise de variância e teste de Tukey (p<0,05). As resinas restauradoras apresentaram películas com espessura maiores que 100 ?m, enquanto as resinas fluidas e os cimentos resinosos apresentaram valores menores que 50 ?m. Os grupos experimentais RZ, RZ45 e RZ60 apresentaram os maiores valores de KHN, RFB e ME. Os grupos RT, RT45, RT60, FT, CV e CR apresentaram os menores valores de RFB e semelhantes entre si. Para a KHN, os grupos RT, RT45, RT60, FZ e CR apresentaram valores intermediários e semelhantes entre si, e superiores aos grupos FT e CV. Os resultados de ?E mostraram valores acima de 2 para todos os grupos experimentais, com exceção do RZ60. Os maiores valores de ?E foram evidenciados nos grupos RT45 e RT60. A razão de contraste foi estatisticamente menor para o grupo CV e os maiores valores de opacidade foram encontrados nos grupos RZ, RZ45 e FZ. A opalescência foi superior nos grupos FZ, CR, FT e CV. Considerando as limitações do presente estudo, concluiu-se que os tratamentos térmicos não alteraram as propriedades mecânicas das resinas restauradoras e não promoveram uma redução da espessura de película que atenda aos requisitos da ISO4049. As resinas fluidas e os cimentos apresentaram espessura de película inferior à 50?m e propriedades mecânicas que atendem à normativa ISO4049. A opalescência maior foi encontrada nos cimentos resinosos e a diferença de cor e razão de contraste apresentaram resposta grupo dependente. / The objectives of this study were to evaluate the physical properties of preheated restorative resin composites and fluid resins with the purpose of cementation of ceramic veneers in comparison to resin cements. Specimens were prepared with two restorative resin composites (Filtek Z250XT and Tetric N Ceram), in the following conditions: room temperature (RZ; RT), heated at 45°C (RZ45; RT45), and heated at 60°C (RZ60; RT60). Two flowable resins (Filtek Z350 Flow and Tetric N Flow) named FZ and FT and two resin cements (Relyx Veneer and Variolink N), called CR and CV, were also used. The experimental groups were evaluated in regards to film thickness with two methodologies; biaxial flexure strength (BFS) and modulus of elasticity (ME) (model 5565, Instron Corp, Canton MA, USA); Knoop microhardness test (KMT) (Shimadzu HMV-2, Tokyo, Japan), color difference (?E), contrast ratio and opalescence test (CM-3770d, Konica Minolta, Japan). Data were assessed by ANOVA and a post-hoc Tukey test (p<0.05). The restorative resins presented film thickness larger than 50?m, whereas the flowable resins and resin cements showed inferior values. The experimental groups RZ, RZ45 and RZ60, revealed greater values of KHN, BFS and ME. The RT, RT45, RT60, FT, CV and CR groups showed lower values for BFS and similar to each other. For KHN the RT, RT45, RT60, FZ and CR groups exposed intermediate and similar values to each other, and superior values to FT and CV groups. Color difference (?E) results demonstrated results superior than 2 for all experimental groups, with the exception of RZ60 group. The greater values of ?E were shown in RT45 and RT60 groups. Contrast ratio was statistically lower for the CV group and the highest values of opacity were verified in RZ, RZ45 and FZ groups. Opalescence was superior in FZ, CR, FT and CV groups. Considering the limitations of this study, the results demonstrated that preheated treatments did not modify the mechanical properties of restorative resin composites and didn\'t reduce film thickness which attend to ISO4049 parameters. Flowable resins and cements obtained film thickness inferior to 50?m and biaxial flexure strength results that are presented by the ISO4049. The greater opalescence was shown in the resin cements, also color difference and contrast ratio revealed results that were group dependent.
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Einblick in die Geschichte der Holzwerkstoffe im Maschinen- und Anlagenbau und aktuelle Möglichkeiten der angemessenen technischen Nutzung / History of wood based materials in mechanical engineering and current possibilities for a benefical technical useEichhorn, Sven, Eckardt, Ronny, Müller, Christoph 16 September 2010 (has links) (PDF)
Der Einsatz von Holz- und speziell Holzfurnierlagenverbundwerkstoffen (WVC) konzentrierte sich in den vergangen Jahrzehnten nahezu ausschließlich auf den Möbelbau und den Bausektor. Eine Verwendung von Holzwerkstoffen im Sinne einer angemessenen technischen Nutzung der vorhandenen Eigenschaften im Maschinen- und Anlagenbau wird hingegen aktuell kaum praktiziert.
Der Vortrag zeigt anhand der Darstellung und Analyse des Standes der Technik Einsatzmöglichkeiten des Werkstoffes im Maschinen- und Anlagenbau auf und charakterisiert dabei die Bereiche, in denen noch verstärkt gearbeitet werden muss, um diese Einsatzmöglichkeiten angemessen nutzen zu können.
Weiterhin werden grundlegend relevante Werkstoffeigenschaften für das angestrebte Einsatzgebiet charakterisiert und erste Einblicke in Bauformen aus WVC gegeben, mit denen ein praktischer Einsatz im Allgemeinen Maschinenbau und damit in der Fördertechnik technisch sinnvoll ist. / For the last decades the usage of plywood materials (Wood Veneer Composites) was mainly focused on furniture and civil engineering. At the moment there is no adequate technical use of wood based materials in mechanical engineering in respect to its particular properties. Following the state of the art several fields of application in mechanical engineering are presented as well as subjects were identified which need further investigation.
Relevant material properties for the aspired technical application are characterized. Furthermore an insight in realized designs of WVC structures is given.
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Ornament : En undersökning av dekorativa element i möbelformgivning och möbler som bärare av dekor. / Ornament : An investigation on decorative elements in furniture design andfurniture as a carrier of ornamentKnutsson, Klara January 2021 (has links)
Målet med det här examensarbetet är att utforska hur jag som möbelsnickare kan använda mig av dekorativa element. Dessutom vill jag söka svar på frågan om hur utvecklingen mot den minimalistiska estetik vi ser idag sett ut och vad den fått för konsekvenser. Undersökningen görs i form av en litteraturstudie där jag tar avstamp i ett källmaterial och diskuterar dekorativa element från flera perspektiv. Litteraturstudien innehåller bland annat en analys av dekorationer ur ett genusperspektiv, en undersökning av begreppet smak samt en reflektion kring hur ornamentik påverkar ett föremåls estetiska hållbarhet. Vidare använder jag mina hantverkskunskaper till att undersöka ämnet genom en fysisk gestaltning. I min gestaltning låter jag det avskalade i dealet representeras av ett bord från IKEA och genom att dekorera det med intarsia möts det minimalistiska med ett mer expressivt uttryckssätt. Min slutsats är att dekorativa element ger en större möjlighet för känslomässig anknytning till ett objekt och att vi hantverkare har chansen att tillfredsställa detta behov. Diskussionen om dekorationers vara eller icke vara är angelägen och bör fortsätta föras och nyanseras inomformgivnings- och hantverkssfären. / The aim of this thesis is to investigate how, in my role a a craftsman, I can use decorativeelements in my work. Furthermore, I seek to answer the question about how the development towards today’s minimalist aesthetics has evolved and what the consequences of this has been. This examination consists of a literature study where I use different sources to discuss decorative elements from a range of perspectives. The study includes an analysis of decoration from a gender perspective, an investigation on the term taste and a discussion on how ornamentation influences the aesthetic s ustainability of an object. Moreover, I use my craftsmanship skills to examine the subject through designing and constructing a physical object. In my design process, I merge the minimalistic ideal as represented by an IKEA table with a decorative element in the form of marquetry. My conclusion is that decorative elements have the possibility to enable emotional connection with an object and a s craftsmenhave the opportunity to satisfy this need. The discussion about the existence of ornamentationis important and should keep being held in the design and craft community.
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Logistiksysteme in der Automobilproduktion aus HolzwerkstoffenEckardt, Ronny, Eichhorn, Sven 23 September 2014 (has links)
Nachwachsende Rohstoffe stellen in zunehmendem Umfang eine sinnvolle Alternative zu herkömmlichen Konstruktionswerkstoffen im Maschinen- und Anlagenbau dar. Speziell Lagenholzwerkstoffe bieten enormes Potential, den Anforderungen an Nachhaltigkeit und Ressourceneffizienz gerecht zu werden, ohne auf eine entsprechende technische Leistungsfähigkeit verzichten zu müssen. In diesem Zusammenhang wird im Vortrag ein an der Technischen Universität Chemnitz entwickeltes Konzept vorgestellt, Metallwerkstoffe (Stahl und Aluminium) im Maschinenbau durch nachwachsende Rohstoffe zu substituieren. Am Beispiel eines in der Automobilproduktion eingesetzten Fördersystems aus Holzwerkstoff wird dieses Konzept erläutert. Dabei handelt es sich um ein im Karosserierohbau bei Volkswagen verwendetes Skidfördersystem. Anhand einer Anforderungsliste wird im Vortrag schwerpunktmäßig der konstruktive Aufbau des Förderers vorgestellt, wobei vor allem die Unterschiede und Besonderheiten zur herkömmlichen Metallbauweise im Vordergrund stehen. Die Berechnung und Auslegung der Transporteinheit erforderte besondere Rechenmodelle, die für die verwendeten Insertverbindungen hergeleitet wurden und im Vortrag kurz erläutert werden. Speziell das dynamische Anforderungsprofil der Anwendung an die Struktur sowie die Verbindungstechnik ist durch bekannte Berechnungsgrundlagen (Bauwesen, Eurocode 5) nicht abgedeckt. Aus diesem Grund werden dem Maschinenbau entstammende Dauerfestigkeitsbetrachtungen speziell für Verbindungen des Ingenieurholzbaus genutzt. Zum Abschluss des Vortrages wird auf den mittlerweile eineinhalb jährigen, störungsfreien Praxiseinsatz bei der Volkswagen AG in Wolfsburg eingegangen und die Vorteile zum herkömmlichen Stahlfördersystem aufgezeigt. / Renewable resources become more and more a useful alternative to conventional construction materials in machine and plant construction. Especially wood veneer composites offer an enormous potential to meet the requirements of sustainability and resource efficiency without having to give up appropriate technical and mechanical capabilities. In this context the University of Technology in Chemnitz has developed a concept to replace metal materials such as steel or aluminum in mechanical engineering by renewable resources. A skid conveyor system made of wood veneer composites in automotive production used by Volkswagen will give a further explanation of this concept. Based on a list of requirements the lecture focuses the structural design. Especially the most notably differences and peculiarities to the conventional metal construction will be shown. The calculation and dimensioning required special calculation models, which have been derived for the used insert joints. Especially the dynamical requirement specifications of the application concerning the structure itself and the joints are not covered by computational models from civil engineering (Eurocode 5). Therefore fatigue strength examinations originated from mechanical engineering were adapted for joints usually used in timber engineering. The speech closes by summarizing the 18 month failure-free operation of totally five conveyor units at Volkswagen in Wolfsburg as well as their advantages compared to the conventional steel conveyor system.
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