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Statické řešení ocelových prvků při požáru / Structural Analysis of Steel Members in FireRunštuková, Monika January 2013 (has links)
This thesis deals with solution of steel members under fire conditions. The goal of the thesis is to examine and compare unprotected steel members with steel members protected by different types of passive protection. Calculation is performed according to applicable design standards. ANSYS software is used for thermal and structural analysis.
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Numerická simulace svařování lopatky a rotoru turbíny. / Numeric simulation welding of the turbine vane and rotorDohnal, Ivo January 2010 (has links)
Numeric simulation welding of the turbine vane and rotor - master’s thesis is ordered by the Siemens Industrial Turbomachinery ltd. company. Simulation welding is done in program SYSWELD. Used welding materials are X22CrMoV12-1 (turbine vane), 30CrMoNiV5-11 (rotor), TOPCORE 838 B (additional material). These are temperature-resistant and fire-resistant welding materials. The SYSWELD program works on the principle of finite elements method. By SYSWELD is done the evaluation of temperature and stress fields and material structure after welding. Here is a part , which deals with computations of welding crevices.
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Structural Behavior of Reinforced Concrete Elements and Subassemblies under Fire Conditions / 鉄筋コンクリート部材および部分架構の火災時構造挙動Mohammad, Mahdi Raouffard 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21066号 / 工博第4430号 / 新制||工||1688(附属図書館) / 京都大学大学院工学研究科建築学専攻 / (主査)教授 西山 峰広, 教授 原田 和典, 教授 河野 広隆 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
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A Numerical Study on the Effect of Concrete Infilling and External Intumescent Coating to Fire-resistant Behaviour of Stub Elliptical Steel Hollow SectionsDai, Xianghe, Lam, Dennis January 2014 (has links)
No description available.
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Phase Change Material : Potential for increased fire resistance in concreteToivanen, William January 2023 (has links)
The European commission has in the Energy Performance of Buildings Directive from 2010 decided that its member states were required to ensure that all new buildings by the end of 2020 were nearly zero-energy buildings. These buildings require small amounts of energy compared to its performance in example by keeping a pleasant indoor climate. To achieve these goals there is an option for integrating phase changing material into building material. The purpose of this project was to determine which kind of PCM is suitable for use in building materials to increase its fire resitance, taking inspiration from the report Fasomvandlingsmaterial: Risker och möjligheter written by Michael Försth, Alexandra Byström and Jonathan Wolf. In particular, the aim was to observe if the application of PCM, in pure powder form, into pure concrete could increase the time until it reaches it critical temperature of 500 °C. The choice of PCM to be used was decided by a literature review and initial thermal tests, and in this case, Magnesium Carbonate Hydroxide Pentahydrate, MCHP, was used as a substitute for the cement, in this project. The project has been carried out through a literature review and laboratory experiments. The laboratory experiments were performed in different stages. First, the thermal properties of the PCM were decided by using a DSC (differential scanning calorimeter) and a TGA (Thermogravimetric analysis). Three kinds of PCMs (Magnesium hydroxide, Aluminium hydroxide and MCHP) were tested from the results of the literature review. The DSC gave a variation in results between the three tested PCMs. MCHP showed two melting phases which produced different kind of fire-retardant products and theoretically would give two instances of stopping the heating of the concrete. With that MCHP was then chosen as the most appropriate one to be incorporated into concrete. From there, pure concrete samples and with PCM mixed in, with different weight percentage varying between 2-10 weight percent (wt.%) of the cements weight, with a thermocouple embedded in the bottom were manufactured. Thereafter, a cone calorimeter was used with the constant heat flux of 50 kW·m-2 as a source of heat radiation. The results shows that the application of the PCM in the concrete by replacing the cement does not give any noticeable increase in its fire resistance by increasing the time until it reaches 500 °C. Neither did it show any signs of the heating curve to flatten out, which in theory would have occurred during melting of the PCM. This could depend on the way the heat transfers down through the concrete and melts the PCM along the way towards the bottom and the thermocouple measuring the temperature. Making the thermocouple only register the heating of the concrete in close proximity to it. Therefore only a small amount of PCM melts and the required energy is not enough to halt the heating. Theoretical calculations performed showed that the melting of the PCM in the case with 5 and 10 wt.% gave an improvement by increasing the time until critical temperature is reached with 4 % and 7.3 %, compared to a pure concrete sample. The melting of the PCM is responsible for 1 % respectively 2 % of that time increased compared to the pure concrete sample. The rest of the increase in time comes from the PCMs thermal properties which is higher than the cement. The literature study shows that there exist many suitable PCM for increasing a building material’s fire resistance, some of which are already used as fire retardants. It also shows that PCM can affect a material’s fire resistance in more ways than just the heat storage (latent heat) in the melting phase. The conclusion of this report is that substituting concrete with MCHP in powder form is not suitable and does not affect the concretes fire resistance. But the usage of PCM in concrete should not be dismissed. There exist different ways to implement the PCM into the concrete which could give a desirable result.
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Bench Scale Characterization of Joints and CoatingsKulkarni, Akhilesh 03 July 2023 (has links)
The ASTM E119 is a large-scale test used to qualify assemblies for fire resistance, including heat transmission and structural integrity. The test requires specialized furnaces and full-scale assemblies that are 3.0 m (10 ft) or more on each side, making it very expensive to perform.
In this study, we investigated the feasibility of the scaling methodology for a reduced-scale fire resistance test on different types of wood-based structures, specifically commercially available intumescent coating applied onto wood and bolted lap joints in wood. We build upon a previously developed scaling methodology for wood and gypsum boards, which integrated geometric scaling, Fourier number time scaling, and furnace boundary condition matching. Intumescent coating presents a particular challenge in scaling in that it expands when exposed to fire conditions. To account for this expansion, we identified a relationship between initial dry film thickness and final expanded thickness through cone calorimeter tests and integrated it into a modified scaling methodology. This approach was then validated through fire exposure tests in furnace on wood samples painted with intumescent coating at full, half, and quarter scales. Finally, we demonstrated the scaling laws for joints under combined thermo-structural loading, by subjecting wood-based half-lap joint samples to combined bending and thermal loading at half and quarter scale. The samples were subjected to static three-point bending with the load scaled to achieve structural similitude, while simultaneously being exposed to a scaled fire exposure on the bottom surface. Our study provides insights into the practical application of scaling methodology for testing the fire resistance of joints and fire-resistant coated wood, paving the way for more cost-effective and quicker fire testing for the wood-based composite industry. / Master of Science / The ASTM E119 is a critical test standard that evaluates the fire resistance of various building materials, including wood-based structures. However, the standard tests are quite expensive due to the need for specialized equipment and large-scale samples. In this study, we explored the potential of using a scaled-down fire resistance test on different types of wood-based materials, including commercially available fire-resistant coated wood and joints.
We built on existing scaling methods for wood and gypsum boards and adapted it to account for the unique properties of intumescent coating - a fire-resistant material that expands when exposed to high temperatures. By conducting a series of tests, we developed a modified scaling approach to accommodate the expansion of the coating.
We then validated this new method by performing fire exposure tests at various scales on wood samples coated with intumescent coating. Finally, we adapted the scaling methods to account for wood based bolted joints. We tested the fire resistance of wood-based half-lap joints under combined heat and structural stress at smaller scales.
Our study offers valuable insights into a more cost-effective and efficient method for testing fire resistance in wood-based structures. By providing a reliable scaling approach for fire-resistant coated wood and joints, our work has the potential to make fire testing more accessible for the wood composite industry, ultimately leading to safer and better-performing buildings.
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A Simple Method to Predict Temperatures in Steel Joints with Partial Intumescent Coating Fire ProtectionDai, Xianghe, Wang, Y.C., Bailey, C.G. 01 1900 (has links)
No / Based on temperatures measured in steel joints with different extents of fire protection, this paper proposes a simple method to calculate temperatures in steel joints with partial intumescent coating fire protection. The method combines the simple temperature calculation methods in EN 1993-1-2 (Committee of European Normalisation CEN, Eurocode 3: design of steel structures—part 1-2: general rules—structural fire design, 2005) for unprotected and protected steel structures through the introduction of an exposure factor, which is the ratio of the unprotected surface area of the joint region to the total surface area of the joint area. Using the measured temperatures for fully protected steel joints, this paper first extracts the effective thermal conductivity of the intumescent coating used in the fire tests. Afterwards, this paper presents validation results based on fire test results on joints with partial fire protection. Finally, this paper presents methods to calculate the exposure factor for different types of partially fire protected steel joints.
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Polydimethylsiloxane Containing Block Copolymers: Synthesis and Characterization of Alternating Poly(Arylene Ether Phosphine Oxide)-B-Siloxane and Segmented Nylon 6,6 -B-Siloxane CopolymersPolk, William David 10 December 2001 (has links)
Two novel classes of siloxane containing, organic-inorganic block copolymers were prepared using different synthetic approaches. The first copolymers were alternating poly(arylene ether phosphine oxide)-poly(dimethylsiloxane) systems, prepared via oligomeric silylamine-hydroxyl reactions. Secondly, segmented nylon 6,6-poly(dimethylsiloxane) block copolymers were synthesized via a non-aqueous adaptation of the "nylon 6,6 salt" hydrolytic polyamidization, using bis(aminopropyl) dimethylsiloxane oligomer as a co-reactant.
Three series of "perfectly" alternating block copolymers were produced from well characterized hydroxyl-terminated poly(arylene ether phosphine oxide) and dimethylamine-terminated poly(dimethylsiloxane) oligomers, in order to investigate both block length and chemical composition effects. Copolymerization in chlorobenzene resulted in high molecular weight materials capable of forming optically clear, nanophase separated films, which displayed unusual morphologies and good mechanical strength. Thermal gravimetric analysis showed high thermo-oxidative stability and increasing char yield with increasing siloxane content. Additional thermal and mechanical investigations provided evidence of selective phase mixing, particularly at shorter block lengths. Surface analysis showed an enrichment of the siloxane blocks at the air-polymer interface in comparison to the bulk state. This behavior increased in proportion to the length of the parent siloxane oligomers. Evaluation of selected optical properties, e.g., refractive indices, revealed linear trends resulting in values of compositionally weighted averages.
Conversely, a series of nylon 6,6-siloxane copolymers were produced from the polycondensation of preformed propylamine-terminated poly(dimethylsiloxane)s, solid nylon 6,6 salt and a corresponding amount of adipic acid to afford siloxane-amide semi-crystalline copolymers with siloxane content ranging from 10 to ~45 wt%. The characterization of high molecular weight and covalent siloxane-amide linkages was hindered by insolubility. For example, crystallinity of the nylon 6,6 precluded the use of common solution techniques, while the susceptibility of the siloxane blocks towards ionic redistribution prevented the use of strongly acidic solvents. However, development of a novel analytical technique using solid state 13C NMR and liquid-solid extraction provided evidence for the presence of covalent bonding between the dissimilar oligomer chains. Thermal gravimetric analysis of resultant copolymers revealed an increase in char yield with increasing siloxane content, a preliminary indicator of increased fire resistance, which was supported by subsequent qualitative Bunsen burner observations. Differential scanning calorimetry showed retention of the polyamide crystalline melt with levels of siloxane incorporation of up to 45 weight %.
In conclusion, two novel classes of polydimethylsiloxane containing block copolymers have been successfully synthesized, despite the complications created as a result of the polar/non-polar interactions developed between a semi-inorganic polydimethylsiloxane and the hydrocarbon based polyarylene ethers and nylon 6,6. / Ph. D.
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Stahlbetonplatten verstärkt mit Textilbeton unter BrandbelastungEhlig, Daniel, Jesse, Frank, Curbach, Manfred 03 June 2009 (has links) (PDF)
Im Rahmen experimenteller Untersuchungen wurden Stahlbetonplatten hergestellt, mit verschiedenen textilen Bewehrungen verstärkt, mit 125 % Gebrauchslast vorgeschädigt und anschließend unter Gebrauchslast mit einer Brandbelastung nach der Einheitstemperaturkurve (ISO-834, Cellulosic curve) beaufschlagt. Alle Platten hielten der Brandbelastung bei gleichzeitiger Biegebeanspruchung mehr als 60 Minuten stand und zeigten weder Betonabplatzungen noch andere optische Schädigungen auf. Die für dieses überraschend positive Ergebnis verantwortlichen Mechanismen werden diskutiert, sind aber noch nicht vollständig verstanden. Eine Schlüsselrolle spielt dabei vermutlich das gute Rissverhalten von Textilbeton und interne Umlagerungen zwischen Textil und Stahlbewehrung.
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Sobre o dimensionamento do revestimento contra fogo de estruturas de aço. / Determination of the fire protective material in steel structures.Guimarães, Patricia Pamplona de Oliveira 30 May 2007 (has links)
A presente Dissertação apresenta algumas metodologias disponíveis para o dimensionamento do material de revestimento contra fogo de estruturas de aço em situação de incêndio. Incluem-se métodos analíticos simplificados conforme normas em vigor e resultados de análises experimentais obtidos por laboratórios internacionais e nacional. Detalha-se também a aplicação do programa de computador Super Temp Calc (STC), em análise térmica e dimensionamento de pilares, revestidos ou não por material de revestimento contra fogo, em contato com alvenarias. Comparações entre esses métodos e sugestões de emprego para a prática de projeto também são contemplados neste trabalho. / This present work shows some methodologies to determine the thickness of the fire protective material in steel structures in a fire situation. It shows analytical methods based on actual standards and results of experimental analysis by international and national laboratories. The application of the program Super Temp Calc (STC) is detailed, by thermal analysis and designs of columns, with fire protection or not, in contact with masonry. Comparisons between some methods and suggestions by use for design´s practical also are contemplated in this work.
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