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.

Im Vortrag werden die Holzwerkstoffe charakterisiert und anderen Konstruktionswerkstoffen und technischen Verbundmaterialien gegenüber gestellt. Anhand eines Ausführungsbeispiels wird deren technologische und wirtschaftliche Leistungsfähigkeit analysiert. Darauf aufbauend werden notwendige Maßnahmen zur Verbesserung der Werkstoffe sowie zu deren Etablierung in der Technik dargestellt. Aus dem Vergleich der jeweiligen Eigenschaftsprofile werden zukünftige Nutzungsmöglichkeiten der Holzwerkstoffe in der Technik abgeleitet. Ein Ausblick zeigt den möglichen Entwicklungsspielraum für Holzwerkstoffe in technischen Anwendungen. / The properties of wood materials are compared to several engineering materials, like metal alloys, polymers and fiber reinforced plastics. The technologic and economic efficiency of plywood is illustrated by the implementation of a wooden beam. Accordingly necessary measures for the improvement of wood materials and their recognition in mechanical engineering are shown. A perspective of further fields of applications for wood materials in a technical context is given.

Over the years a significant decline in employment had occurred in the Douglas-fir region’s lumber and wood products industry. High levels of unemployment can lead to undesirable economic and social effects. An understanding of the nature of unemployment can facilitate future planning as well as mitigating current problems. This study has attempted to examine the underlying causes of employment decline in the region’s softwood lumber and plywood industries, specifically over the period 1979-86. This time span is of particular importance since there was a rapid decline in employment levels after 1979. There has been much controversy over the causes of this reduction but no comprehensive empirical analysis was ever undertaken to determine its cause. Meanwhile levels of output, which also declined in the early part of this span, have again reached pre-recession levels. A cost function approach was employed as the basis of the empirical analysis. The results suggest that most of the employment decline in these industries has been caused by changes in the structure of production and by increasing labour productivity. Although there are indications of cyclical unemployment, much of the reduction in the industries' labour force seems to be attributable to greater substitution of capital and logs for labour. Simulation analyses tend to suggest that changes in factor prices would not have had any dramatic effect on employment levels. It was found that of the recent employment decline in the two industries, around one-quarter of the loss in the lumber industry and one-third in the plywood industry are caused by cyclical forces. Structural factors were assumed to be the cause of the remaining loss in levels of labour input.

The detailing of many important and essential aspects of a building are initially neglected and thought of as a last step before the completion of a project, starting with the large scale working down to the small scale. They’re usually treated secondary and the general scheme is prioritized. Superficial and assembled rather than detailed and how it’s assembled. This creates a dilemma when necessary elements of a building begin to be considered how to be built and are treated as a problem, when it should be considered as an opportunity. More often than not, the product of a detail is a solution to a problem that was created. Not meaning the problem could’ve been avoided, the problem still needed to be solved regardless, but it was solved out of necessity and not as an asset to the project. This project was not about working backward, starting with a detail and working outwards to create a whole, to assemble fragments without any real sense of bearing. I didn’t use the detailing of the project just for the sake if it, to solve a problem that perhaps didn’t need to be solved. Instead embrace the challenge of a given situation as a seed from which a design process can grow. By briefly zoom in on a specific situation I hoped to develop a common language of the building as a whole. To create something that belongs to the building and not considered as an addition.

The current method for estimating wood failure is highly subjective. Various techniques have been proposed to improve the current protocol, but none have succeeded. This research aims to use deep learning/semantic segmentation using SegNet architecture to estimate wood failure in four types of three-ply plywood from mechanical shear strength specimens. We trained and tested our approach on custom and commercial plywood with bio-based and phenol-formaldehyde adhesives. Shear specimens were prepared and tested. Photographs of 255 shear bonded areas were taken. Forty photographs were used to solicit visual estimates from five human evaluators, and the remaining photographs were used to train the machine learning models. Twelve models were trained with the combination of four image sizes and three dataset splits. In comparison to visual estimates, the model trained on 512 × 512 image size with 90/10 dataset split had a mean absolute error (MAE) of 6%, which was the best among the literature.

For structural engineers, the two most important design criteria are utility andsafety. It is about making sure that a structural component is reliable enough not toendanger any of a building's users, while at the same time being as sustainable andefficiently designed as possible. In other words, an element must be safe enough towithstand the improbability and sufficiently cheap to be relevant for the design.Considering this, using a material such as wood instead of metal may prove to be asustainable alternative for certain building components.Timber can be designed to sustain high temperatures and fire; it has a high strengthrelative to its weight and is naturally produced. Furthermore, an engineered woodproduct such as birch plywood has proven very strong in structural applications,especially when glued. Therefore, birch plywood has great potential as a reliablematerial in structural components. In this work, a total of 24 specimens with birchplywood connections were tested experimentally.The specimens were designed to enforce stress states that would occur in actualtrusses. Additionally, Specimens were assembled with two different connectionmethods, one being a dowel-type connection and the other being a glued-type. Eachtype of connection was tested in both tension and compression, with a total of threerepetitions each. For the glued-type specimens, birch plywood plates wereinvestigated in three different angles to the face grain; 0°, 5° and 15°. Theload-displacement relationships and the failure modes are of specific interest in thisthesis.Test results showed that failure modes were semi-brittle and distinct, and the testsshowed that glued-type connections withstood 37% higher loads than dowelledtypes. Specimens might withstand even higher loads if gluing were performed in amore controlled environment. The load-to-face-grain angle of plywood also had asignificant impact on the capacity of connections. For the 0°-specimens with gluedconnections tested in compression, no failures occurred in the plywood, and testsreached loads as high as 82 kN. Calculations were made estimating the load capacityas high as 95 kN, but possibly a more realistic approximation would be 85 kN. Thiswould imply that the 0°-specimens are around 20% stronger than the 15°-specimensand approximately 17,7% stronger than the 5°-specimens tested in compression.Birch plywood is promising to be used in connections of timber structures whereplates transfer forces between structural elements.

[pt] Os materiais e processos atualmente utilizados pela indústria naval na construção de embarcações de lazer em materiais compósitos apresentam diversos riscos à saúde do trabalhador. Resinas, tintas e vernizes liberam vapores tóxicos durante sua cura num processo que pode durar até sete dias. O presente trabalho, de maneira prática, buscou adaptar técnicas consagradas a materiais inovadores no estudo de processos produtivos alternativos, onde o contato do trabalhador com substâncias tóxicas fosse mitigado. Num primeiro momento procurou-se entender as propriedades das fibras e resinas de origem vegetal e seu potencial no desenvolvimento de materiais compósitos, bem como o estado da arte em que se encontravam as pesquisas correlatas no LILD (Laboratório de Investigação em Living Design da PUC-Rio). Em seguida, rabalhou-se no desenvolvimento de painéis em sanduíche laminados a vácuo. Por fim, as etapas se concatenam na construção de uma pequena embarcação a vela. Durante o processo construtivo e o convívio laboratorial buscou-se estabelecer relações com os métodos e materiais convencionais, situando a pesquisa mais no campo da técnica do que em um estudo puro da resistência dos materiais. Acreditamos que as características de trabalho são tão importantes quanto a resistência do material, principalmente quando se atua diretamente no processo construtivo. Desta forma, procuramos por materiais disponíveis e técnicas de simples implementação, com um mínimo de investimento em infra-estrutura e mão de obra, em busca de uma embarcação confiável. Técnicas de trabalho com materiais compósitos foram testadas devido as características do projeto da embarcação, uma canoa outrigger a vela: colagem, hand lay-up e laminação a vácuo. Os resultados foram promissores, traduzidos numa embarcação robusta e, ainda assim, leve e graciosa. / [en] Composite boatbuilding methods used nowadays represent several risks to worker s health. Resins, hardeners and varnishes liberate toxic organic vapors in the curing process that can take up to 7 days. The present work tried in a practical approach to adapt innovative materials with standard building methods in the research for an alternative productive process that can mitigate workers exposure to toxic substances. At first, we focused on understanding the properties of natural fibers and castor oil polyurethane resins and their potential possibilities on the development of composite materials, as well as understanding the state-of-art of correlated researches at LILD (living design free investigation laboratory). Afterwards, we developed vacuum bagged sandwich composite panels with the studied materials, which finally were used to build of a small sailing craft. Several issues were brought to debate during workshop cooperative work. Establishing connection with conventional boatbuilding methods showed the research was about technique instead of material resistance. We believe that the practical daily construction needs are as much important as the material resistance itself, especially if you aim to work directly on the building process. With that in mind we went for available materials and simple low cost technologies in the search for a reliable boat. Several composite materials techniques were tested due to the boat s project characteristics (an outrigger sailing canoe): bonding, hand lay-up, vacuum bagging etc. Results were promising, shown on a robust yet light and graceful vessel.

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Im Forschungsprojekt wurde eine Bauweise für ein modular aufgebautes und flexibel einsetzbares Gestellsystem entwickelt, welches durch integrativen Leichtbau den vorteilhaften Einsatz von Holzfurnierlagenverbund-werkstoffen (WVC) für Verarbeitungs- und Fördermaschinen ermöglicht. Die ingenieurtechnisch relevanten Eigen-schaften des Holzbasiswerkstoffs (u.a. strukturelle Dämpfungseigenschaft) wurden ermittelt und darauf aufbauend ein Profil als Strukturelement des Gestellsystems entwickelt. Hier lag besonderes Augenmerk auf der Gestaltung des Profilquerschnitts. Es wurden verschiedene Querschnittsgeometrien vergleichend untersucht, wobei sich ein ge-schlossenes Kastenprofil als günstig erwies. Ausgehend vom entwickelten Profil wurde die für ein modulares Sys-tem notwendige Verbindungstechnik konzipiert. Folgend wurde schrittweise die modulare Bauweise in Strukturein-heiten umgesetzt sowie parallel Untersuchungen zu Steifigkeit und Festigkeit der Profile fortgeführt. Während der Erprobung von Struktureinheiten unter praxisnahen Bedingungen wurden gewisse konstruktive Verbesserungspo-tentiale deutlich. Diese Änderungen sowie die gewonnenen Erkenntnisse aus der Material- und Strukturprüfung kamen im Prototyp zur Umsetzung. Schallpegelprofile verschiedener fördertechnischer Anlagen und des entwickel-ten Prototypen wurden abschließend aufgenommen und verglichen. / Aim of the present study was to develop a modular designed and widely employable rack system. Positive properties of wood based materials (WVC) in lightweight structures were identified and integrated for the application in fabri-cation and conveyer technologies. For this purpose relevant properties of wood materials had been investigated (e.g. damping properties). The results of these analyses were the basis for the development of a beam profile, the basic structural design element for the future rack system. The most effort was put into finding the optimal beam cross section. Several different cross sections had been compared, a square sectional beam profile showed the best per-formance. Based on the square sectional beam profile proper connection methods for the modular rack were devel-oped. Structural units were subsequently realized step by step, while the investigation of stiffness and strength of the profiles was continued. The testing of the structural units under simulated field conditions revealed some minor constructional improvement capabilities. The constructional improvements and the knowledge from the material and profile testing were put into practice in the prototype. Finally sound measurements were carried out to compare several conveyors made of different materials (including the prototype) in respect to the emitted sound level.

Durch die Entwicklung der vorgestellten modularen Bauweise ist es möglich, Maschinengestelle aus Holzfurnierlagenverbundwerkstoff (WVC) einfach herzustellen und technisch sinnvoll einzusetzen. Die modulare Bauweise kann sowohl für statische als auch dynamische Beanspruchungen im Allge-meinen Maschinenbau angewendet werden. In einem Baukastensystem werden Maschinenteile aus WVC durch geeignete Verbindungsmittel lösbar zusammengesetzt. Damit ist es möglich, eine hohe Flexibilität in der späteren Nutzung mit einer hohen Variantenvielfalt des Aufbaus durch entsprechend verschiedene Bauteile zu kombinieren. Im Vortrag werden die verschiedenen Belastungen des Holzverbundes im Maschinenaufbau charakte-risiert und auf Probleme bei der Konstruktion eingegangen. Abschließend werden Ergebnisse zu Dau-eruntersuchungen der Verbindungstechnik und des gesamten Maschinenaufbaus vorgestellt und diskutiert. / The development of the presented modular construction allows to manufacture wood veneer compos-ite (WVC) machine racks easily in a technical reasonable way. The modular construction can be used for both static and dynamic loading conditions in mechanical engineering. In the modular construction system the WVC machine components are connected detachable with adequate fasteners. This leads to high flexibility during the construction and assembly process of machine components. In the current presentation the different loading conditions of WVC profiles are characterized and the problems during construction described. Finally the results of the long term testing of the connection technique are presented and the complete machine system is discussed.