Face checking in decorative maple veneered plywood panels is a significant problem for hardwood plywood manufacturers, furniture makers, cabinetmakers, and consumers. Efforts made by panel producers and researchers to minimize checking conducted to-­‐date have been limited, and produced contradictory results. In this study the impact of four manufacturing factors believed to contribute to check development in decorative maple veneer panels were determined. The factors investigated were face veneer thickness and preparation, lathe-­‐check orientation, adhesive and core type. An efficient, automated, optical technique based on digital image correlation principles was developed and used to detect and measure checks as they develop. The novel new method for characterizing check severity and development was effective in efficiently measuring checking for a substantial number of samples. The results of the factor screening analysis reveal intricate four way interactions between factor levels contribute to check development, and that some combinations are likely to exhibit much more checking than others. / Graduation date: 2013

This thesis project revolves around the last days of an abandoned building in decay, facing demolition. It is situated in Värtahamnen, a harbor area in Stockholm. The area is the subject of a major urban planning project in the upcoming decade. In my project my aim is to contemplate this condition of of a building and how to approach and use the ephemerality of architecture and design in the creative process. By extracting different material behaviors caused by decay and exploring them experimentally, a diverse “buffet” of design concepts and methods are presented. The project also orbits around the subject of preservation, a topic commonly debated during interventions in the built heritage. Instead of taking a stand for or against the demolition of the building, the field of experimental preservation is used as a theoretical and methodological background in the design process, as a way to expand the scope on how to navigate and work artistically with preservation. In conclusion, this project tries to revise our perspective on the concept of decay as something destructive and instead suggest the creative potential in understanding it. It also contributes with reflections and speculations on how we can find new creative strategies for taking the whole lifespan of a design project into account already from the beginning.

O OSB é um produto derivado da madeira desenvolvido nos Estados Unidos em 1970. É definido como um painel de partículas orientadas, as quais são distribuídas em camadas múltiplas de uma forma predeterminada. À época, o OSB foi criado para substituir o painel de madeira compensada. Todavia, geralmente suas propriedades na flexão estática são inferiores. A proposta principal deste trabalho foi produzir e analisar o desempenho de painéis OSB de Pinus sp e resina poliuretana à base de óleo mamona com inclusão de telas metálicas, objetivando acréscimo nas propriedades de resistência e de rigidez na flexão estática. A produção seguiu o processo laboratorial, consistindo em gerar as partículas, distribuir o adesivo, confeccionar o colchão e prensar à temperatura de 100°C por 10 minutos. O teor de resina adotado foi de 12% tendo como base a massa seca das partículas. Os painéis foram confeccionados com três camadas, as externas tendo direção paralela ao comprimento da chapa e a interna com distribuição randômica. A proporção face/miolo/face foi na faixa de 20:60:20. Com base nas recomendações de documentos normativos brasileiros e europeus foram realizados ensaios de flexão estática, de onde foram determinados os módulos de ruptura (MOR), e módulo de elasticidade (MOE), ensaios de arrancamento de parafusos, adesão interna, teor de umidade, absorção de água, inchamento em espessura e determinação da densidade aparente. Os resultados apontam a eficiência dos painéis OSB produzidos quando comparadas suas propriedades com os valores mínimos exigidos pelas normas e valores encontrados na literatura para painéis desta natureza. A utilização da tela metálica se mostrou não necessária, dada a pouco relevante diferença de MOE e MOR entre os painéis com e sem a tela. / OSB is a wood based product developed in the United States, since 1954. It\'s defined as oriented particles panels, which are distributed in multiple layers of a predetermined shape. At the time, the OSB was created to replace the plywood panel, but usually its bending properties are inferior. The main purpose of this study was to produce and analyze the performance of OSB from Pinus sp and castor oil based polyurethane resin with inclusion of metallic gauzes, aiming to increase strength and stiffness properties in static bending. Panel production followed laboratory process, consisting of particles generation, adhesive distribution, mattress making and a pressing in 100ºC temperature for 10 minutes. The resin content was set at 12% based on particles dry weight. Panels were produced with three layers: the outers with strands in direction parallel to the panel length; internal in randomized distribution. Face/core/face particle proportion was in range of 20:60:20. Based on Brazilian and European codes recommendations, several tests were performed to determine: modulus of rupture (MOR) and modules of elasticity (MOE), in static bending; screw pullout; internal adhesion; moisture content; water absorption; thickness swelling and density. Results showed efficiency of OSB produced comparing their properties with basic codes requirements the standards and literature values for such panels. The use of metallic gauze has been shown not necessary, because of small relevant difference between MOE and MOR for panels with and without gauze inclusion.

In this thesis, the moisture characteristics of spruce plywood are studied experimentally and numerically with special attention given to moisture storage and release as the indoor humidity changes diurnally. This is referred to as the moisture buffering capacity. Two test facilities (a glass jar facility and a transient moisture transfer facility) are used to measure the moisture accumulation and temperature and relative humidity profiles within spruce plywood. These measured data are used to determine the moisture buffering capacity of spruce plywood and validate a one-dimensional transient numerical model that can be used to calculate the transient heat and moisture transfer in spruce plywood. There is good agreement between the measured and simulated results over the range of test variables investigated. </p><p>This validated numerical model is used to investigate the effect of initial conditions, boundary conditions, thickness and humidity step change on the moisture buffering capacity. In addition, sensitivity studies are performed to investigate the effect of variations in material properties used in the numerical model. The properties that are considered in these sensitivity studies are the sorption isotherm, effective thermal conductivity, heat of sorption and effective diffusion coefficient. These studies show that the sorption isotherm has the greatest effect on the moisture buffering capacity, as well as the temperature and relative humidity profiles within spruce plywood. For example, a ± 10% change in sorption isotherm has a ± 7%, ± 6% and ± 10% effect on the moisture buffering capacity, and the relative temperature and relative humidity change, respectively. </p><p>This thesis also verifies the moisture diffusivity property for spruce plywood, which was developed by Olutimayin and Simonson (2005) to account for moisture storage in cellulose insulation for a single step change in humidity. It was found that for spruce plywood, the moisture penetration depth may be over predicted by an order of magnitude when moisture storage is neglected using a transient analytic solution which does not include moisture storage.

Nefab Plypak AB i Habo bedriver produktion och försäljning av lådor och väskor för långvarigt produktskydd. De har identifierat behovet av att rationalisera montering av beslag på sina produkter. Idag monteras beslagen genom nitning vilket är en väl beprövad metod som använts under lång tid. Behovet av mer rationell montering skapade underlag för detta examensarbete innefattande vidareutveckling av monteringsmetoder. Kravet på möjligheter till automatiserad montering har påverkat utvecklingsprocessen mot att utveckla fästen som inte kräver ytterligare komponenter eller arbetsmoment i monteringen. De nya koncepten måste uppfylla samma krav avseende belastning och robusthet som dagens komponenter. Resultatet av utvecklingsarbetet är ett koncept där befintlig handtagsdel används tillsammans med en nyutvecklad fästdel. Den nya fästdelen är utformad för att ersätta de tre komponenterna på den befintliga lösningen. Genom att fästet försetts med så kallade nabbar* som pressas fast i plywooden behövs inte längre någon nit eller annat fästelement. Nabbarna är försedda med flikar** vilket ger en stark och tillförlitlig lösning. Konceptet bygger på rationell montering med ett pressverktyg och kan med fördel ingå i automatiserad monteringsprocess. / Nefab Plypak AB is a producer of plywood boxes and cages used for long-term product protection. They are also a supplier of all types of long term packaging boxes. Nefab have identified the need of cut costs through rationalization of their mounting process of the fittings. The current method Nefab uses for mounting their fittings is rivet, which is a method that has been used for a long period of time. Rivet is a well known method for its reliability, though not easy to rationalize to a further level. This fact has made a good background to investigate possibilities to find new mounting methods. Nefab have a strategy to implement an automatized production, which have influenced the development process to develop something that would not need any additional components or extra steps in the mounting process. The new concepts need to fulfill the present requirements considering the force of load as well as the strength. The result of the development process is a concept that uses current handle part with a brand new solution for the fitting part. The new part is developed to replace the current three parts, rivet, plastic cover and fitting. The new fitting is designed with a sort of hooks that will be pressed through the plywood and lock the construction, which allow a design without a rivet. The hooks are designed with a barb that will lock the fitting, which provides a secure and strong solution. The concept is based on a rational mounting process and can be a part of an automatized mounting process.

In this thesis, the moisture characteristics of spruce plywood are studied experimentally and numerically with special attention given to moisture storage and release as the indoor humidity changes diurnally. This is referred to as the moisture buffering capacity. Two test facilities (a glass jar facility and a transient moisture transfer facility) are used to measure the moisture accumulation and temperature and relative humidity profiles within spruce plywood. These measured data are used to determine the moisture buffering capacity of spruce plywood and validate a one-dimensional transient numerical model that can be used to calculate the transient heat and moisture transfer in spruce plywood. There is good agreement between the measured and simulated results over the range of test variables investigated. </p><p>This validated numerical model is used to investigate the effect of initial conditions, boundary conditions, thickness and humidity step change on the moisture buffering capacity. In addition, sensitivity studies are performed to investigate the effect of variations in material properties used in the numerical model. The properties that are considered in these sensitivity studies are the sorption isotherm, effective thermal conductivity, heat of sorption and effective diffusion coefficient. These studies show that the sorption isotherm has the greatest effect on the moisture buffering capacity, as well as the temperature and relative humidity profiles within spruce plywood. For example, a ± 10% change in sorption isotherm has a ± 7%, ± 6% and ± 10% effect on the moisture buffering capacity, and the relative temperature and relative humidity change, respectively. </p><p>This thesis also verifies the moisture diffusivity property for spruce plywood, which was developed by Olutimayin and Simonson (2005) to account for moisture storage in cellulose insulation for a single step change in humidity. It was found that for spruce plywood, the moisture penetration depth may be over predicted by an order of magnitude when moisture storage is neglected using a transient analytic solution which does not include moisture storage.

<p>Nefab Plypak AB i Habo bedriver produktion och försäljning av lådor och väskor för långvarigt produktskydd. De har identifierat behovet av att rationalisera montering av beslag på sina produkter. Idag monteras beslagen genom nitning vilket är en väl beprövad metod som använts under lång tid. Behovet av mer rationell montering skapade underlag för detta examensarbete innefattande vidareutveckling av monteringsmetoder.</p><p>Kravet på möjligheter till automatiserad montering har påverkat utvecklingsprocessen mot att utveckla fästen som inte kräver ytterligare komponenter eller arbetsmoment i monteringen. De nya koncepten måste uppfylla samma krav avseende belastning och robusthet som dagens komponenter.</p><p>Resultatet av utvecklingsarbetet är ett koncept där befintlig handtagsdel används tillsammans med en nyutvecklad fästdel. Den nya fästdelen är utformad för att ersätta de tre komponenterna på den befintliga lösningen. Genom att fästet försetts med så kallade nabbar* som pressas fast i plywooden behövs inte längre någon nit eller annat fästelement. Nabbarna är försedda med flikar** vilket ger en stark och tillförlitlig lösning. Konceptet bygger på rationell montering med ett pressverktyg och kan med fördel ingå i automatiserad monteringsprocess.</p> / <p>Nefab Plypak AB is a producer of plywood boxes and cages used for long-term product protection. They are also a supplier of all types of long term packaging boxes. Nefab have identified the need of cut costs through rationalization of their mounting process of the fittings. The current method Nefab uses for mounting their fittings is rivet, which is a method that has been used for a long period of time. Rivet is a well known method for its reliability, though not easy to rationalize to a further level. This fact has made a good background to investigate possibilities to find new mounting methods.</p><p>Nefab have a strategy to implement an automatized production, which have influenced the development process to develop something that would not need any additional components or extra steps in the mounting process. The new concepts need to fulfill the present requirements considering the force of load as well as the strength.</p><p>The result of the development process is a concept that uses current handle part with a brand new solution for the fitting part. The new part is developed to replace the current three parts, rivet, plastic cover and fitting. The new fitting is designed with a sort of hooks that will be pressed through the plywood and lock the construction, which allow a design without a rivet. The hooks are designed with a barb that will lock the fitting, which provides a secure and strong solution. The concept is based on a rational mounting process and can be a part of an automatized mounting process.</p>

Digital images acquired at construction sites contain valuable information useful for various applications including As-built documentation of building elements, effective progress monitoring, structural damage assessment, and quality control of construction material. As a result there is an increasing need for effective methods to recognize different building materials in digital images and videos. Pattern recognition is a mature field within the area of image processing; however, its application in the area of civil engineering and building construction is only recent. In order to develop any robust image recognition method, it is necessary to choose the optimal machine learning algorithm. To generate a robust color model for building material detection in an outdoor construction environment, a comparative analysis of three generative and discriminative machine learning algorithms, namely, multilayer perceptron (MLP), radial basis function (RBF), and support vector machines (SVMs), is conducted. The main focus of this study is on three classes of building materials: concrete, plywood, and brick. For training purposes a large-size data set including hundreds of images is collected. The comparison study is conducted by implementing necessary algorithms in MATLAB and testing over hundreds of construction-site images. To evaluate the performance of each technique, the results are compared with a manual classification of building materials. In order to better assess the performance of each technique, experiments are conducted by taking pictures under various realistic jobsite conditions, e.g., different ranges of image resolutions, different distance of camera from object, and different types of cameras.

Thesis (Ph.D.) - University of Queensland, 2005. / Includes bibliography.

Le bois est un matériau naturel qui partage avec d’autres matériaux cellulaires la propriété de pouvoir subir par exemple de fortes déformations de compression avec un effort stable jusqu’à densification. Cette propriété est particulièrement recherchée dans le cas de structures devant subir des chocs. Le bois est ainsi utilisé dans la conception de conteneurs pour produits radioactifs, et dans la structure isolante de méthaniers. Dans ce dernier cas, il peut être soumis à de fortes déformations, à grande vitesse de déformation, et pour des températures ambiantes à cryogéniques. Pourtant, le comportement du bois et plus particulièrement dans le cas des méthaniers, le comportement du contre-plaqué, n’est que très peu étudié dans ces conditions extrêmes de température cryogéniques et de grande vitesse de déformation. De plus, l’influence de la teneur en humidité du bois sur son comportement en sollicitation sévère n’est que très peu connue. Ces sujets sont au coeur de ce travail de doctorat, avec d’abord l’étude du comportement en compression hors plan d’un contre-plaqué de bouleau de la température ambiante à cryogénique de 100K, pour des vitesses de déformation du régime quai-statique à plusieurs centaines par secondes, et pour des humidités du bois de 2 à 15% ; ensuite par des essais en cisaillement qui ont été effectués à grande vitesse de déformation pour une humidité de 8%. La réalisation de ces essais a nécessité le développement de nouveaux montages et la mise au point de protocoles dont les validations sont discutées à partir de comparaisons aux essais normalisés. / The wood is a natural cellular material. Like other cellular materials, wood is able to carry a stable load under compression up to the densification. This is a key property for the use of cellular materials and wood based materials for cushioning and choc absorber design. Wood is for example used for radioactive material containers and plywood is involved in the insulation complex of LNG carriers. In this case, plywood may be submitted to high strain rate loads at cryogenic temperature. However, the behaviour of plywood under such extreme conditions is not well established in the literature, nor the influence of the moisture content on the mechanical behaviour in such conditions. In the present study, the out of plane compression behaviour of birch plywood is presented for ambient down to cryogenic temperatures, for strain rate from 0,001 up to 700/s and for moisture contents in the range 2-15%. Shear tests are also presented far various strain rates at ambient temperature and 8% moisture content. The apparatus specially designed and the test protocols are discussed, and the results compared to international standards when available.