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Hodnocení historických konstrukčních spojů během vývoje úložného nábytku, jejich využití a optimalizace v současných podmínkách.
Záborský, Vladimír ; Gaff, Milan (advisor)
Dizertační práce zpracovává historický vývoj konstrukce a použitých materiálů úložného nábytku od 17. až po začátek 20. století a jej propojení (aplikaci) na současnou nábytkovou tvorbu.
Zaměřuje se na rozbor vlastností spojů používaných ve výrobě nábytku. Na vybraných typech spojů nábytku budou vykonané experimentální testy, kde se bude zkoumat vliv rozměrů jednotlivých částí konstrukčních elementů vybraného typu spoje a druhu dřeviny na pevnost nábytkových spojů. Rovněž se bude zkoumat vliv typu použitého lepidla. Vybrané druhy lepidel budou určeny na nábytkové konstrukce.
Jednotlivé pevnosti vybraných nábytkových spojů budou analyzovány s výpočtovým modelem pomoci metody konečných prvků. Pomocí počítačové simulace se budou jednotlivé typy nábytkových spojů porovnávat, s cílem najít nebezpečné koncentrace napětí. Tyto údaje poskytnou pro konstruktéry informace, kde je nutné daný materiál zesílit, případně zvětšit geometrické parametry konstrukčních elementů. Předpokládaným výstupem předkládaného projektu je návrh nových geometrických parametrů konstrukčních elementů a korekce dlouhodobě zažitých nedostatků uplatňovaných při tvorbě spojů.
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Thermowood properties depending on the protective substances
Kroupa, Michal ; Gaff, Milan (advisor) ; Sarvašová Kvietková, Monika (referee)
Bachelor thesis Thermowood properties depending on the protective substances is divided into several chapters. The first chapter explains the concept ThermoWood, the second chapter focuses on wood modification, the third chapter deals with the properties of wood ThermoWood. The fourth chapter shows the impact on the environment ThermoWood. The fifth chapter focuses on the analysis of literary knowledge, chapter sixth chapter is devoted to the analysis of the use of paints in practice. The penultimate seventh chapter is dedicated to new trends in this area and the last eighth chapter shows the graphs of the Finnish ThermoWood companies that are focused on production statistics.
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Trends in the design and creation of new materials
Rodrová, Veronika ; Gaff, Milan (advisor) ; Borůvka, Vlastimil (referee)
The objective of my research is to examine the influence of densified wood in combination with native wood on its mechanical properties such as moduls of elasticity, bending strength, limit of proportionality, bendability coefficient and tensile-shear strength of glued line.
The examined woods are Europen beech (Fagus Sylvatica L.) and Aspen (Populus tramula L.). The tests were carried out on speciemens with different thickness. The densification by 10% and 20% was performed. For the glued joint polyurethane adhesive and polyvinylacetate glue were used.
The thesis includes simulation of the properties, their computer program tetsing, and the comparsion with the values obtained from real measurement. The purpose of this part of thesis is to achieve a simulation that will replace laboratory tests or disprove this method of scientific research and deepen our knowledge of proceses occuring during the pursued way of stress.
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Trends in the design and creation of new materials
Kašičková, Václava ; Gaff, Milan (advisor) ; Babiak, Marian (referee)
Thesis investigates the flexural properties of modified laminated wood. Thesis examined two wood species - beech and aspen. The aim was to describe effect of wood species, material thickness, densification, adhesives and loaded cyclic stress on selection of mechanical properties.
Wood species and thickness of material were determined as factors with very significant impact. They affected modulus of elasticity, limit of proportionality and bending strength. All these characteristics achieved higher values while testing beech lamellas. Degree of densification does not appear as a very significant factor. Comparing modulus of elasticity in this thesis and data given in the literature it is possible to say that densified lamellas used in this research reached higher values.
This thesis also investigates tensile-shear strength and bendability.
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Manufacture of wooden frame into Old English furniture.
Špalek, Jan ; Gaff, Milan (advisor) ; Ruman, Daniel (referee)
This bachelor thesis is focused on the production of wooden frames into the Old English furniture. The aim is thematically coherent handle the technological process for the production of the wooden frames in company Jan Špalek Rámařství. Assess the current state of production and on the basis lessons learned suggest possible improvements. We chose one representative product, which is one of the most produced. We described technological production method on the basis of experience with the production. According to the technological method of production and description of current state of the company, we think about the shortcomings. After finding these shortcomings, we dealt with the proposal of new possible solutions that the company could use for innovation.
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Trends in design and development of new materials
Jiřištová, Eliška ; Gaff, Milan (advisor) ; Kminiak, Richard (referee)
This bachelor thesis is focused on trends in design and production of new materials, especially materials made of wood or other natural materials. First part of this thesis provides survey about different ways of wood modifications, which lead to production of new materials. There is an overview of well known modifications and treatments of wood with some examples. Further there are presented three new ways of wood modifications. In the next part there is a description of chosen materials, which are based on wood or other natural materials. These materials are made with respect to environment. They are new on market and they have big potential, mainly because of their unusual design and eco-friendly production.
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Mechanical properties of the lamellae materials
Vokatý, Vojtěch ; Gaff, Milan (advisor) ; Babiak, Marian (referee)
This thesis evaluated experimental research on the influence of selected factors (species, thickness, density, number of stress cycles) on the specified material characteristics (modulus of elasticity, modulus of rupture, limit of proportionality, bendability coefficient). The measured values were statistically evaluated and expressed in tables and graphs. Beech (Fagus Sylvatica L.) was selected to represent hardwood and aspen (Populus Tremula L.) softwood.
Tree species affects all observed characteristics. The results show that the modulus of elasticity increases with increasing densification of the material, but decreases with the increasing thickness of the material. A similar dependence is observed even with the modulus of rupture and limit of proportionality, which is also dependent on the number of cycles. The bendability coefficient is affected by material thickness.
It is expected that based on the evaluation of the results it will be possible to design materials with tailored properties.
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Principles targeted Edit the properties of layered materials
Houžvíček, Petr ; Gaff, Milan (advisor) ; Gašparík, Miroslav (referee)
Target of the thesis was an investigation of the influence of selected factors (tree species, thickness of material, type of glue and cyclic loading) and their combinations on strength properties of laminated lumber. This measured properties were: bending strength, modulus of elasticity, limit of proportionality, coefficient of bendability and shear strength of glued joint.
Most important factor for bending strength, modulus of elasticity and limit of proportionality was the tree species. For coefficient of bendability and shear strength of glued joint the most important was the material thickness. Influence of cyclic loading and type of glue, weren´t proved.
After that, we simulated our investigation which we made in computer program based on finite element method. The simulation corresponded just for thicker tested samples.
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