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Aplicação comparativa de métodos de mapeamento de riscos de incêndio nos centros urbanos das cidades de Coimbra e Porto Alegre / Comparative application of methods for mapping fire hazard in urban centers of the cities of Coimbra and Porto AlegreLucena, Renata Batista January 2014 (has links)
As ocorrências de incêndios nas edificações têm aumentado cada vez mais no Brasil e em outros países. Para as soluções deste problema, grupos acadêmicos, corpos de bombeiros e demais autoridades responsáveis pela segurança contra incêndio vêm realizando vários estudos relacionados à prevenção e proteção contra incêndio, buscando sempre aprimorar as legislações e procedimentos já existentes nesta área. Porém, as legislações ainda não são adequadas para os edifícios antigos, incluindo praticamente todos os centros urbanos. Os centros urbanos, geralmente locais antigos, concentram a maior parte dos estabelecimentos de comércios da cidade, o que significa elevado número de pessoas circulando por esses locais. A ocorrência de um incêndio em um centro urbano pode causar vários danos e perdas relacionados, tanto com o patrimônio histórico que representa a memória da cidade, quanto aos relacionados à vida humana, sendo estes os de maior gravidade. Deste modo, estudos de mapeamento de risco de incêndio estão sendo desenvolvidos nas edificações de centros urbanos antigos, com o fim de diagnosticar o risco existente e, com isso, verificar maneiras para que este risco seja menor e aceitável, objetivando o seu controle antes mesmo que se propague. Esta pesquisa trabalha com dois métodos semiquantitativos de mapear risco de incêndio em edifícios localizados nos centros urbanos da cidade de Coimbra/Portugal e Porto Alegre/ Brasil; sendo estes nomeados de Método de Gretener e FRAME, que buscam quantificar o risco através de análises construtivas, geométricas e de segurança contra incêndio. Os resultados do trabalho nos dois centros urbanos indicaram que os fatores de segurança contra incêndio são baixos e considerados inadequados para esta ocupação. A área estudada da Cidade de Coimbra ficou com um resultado mais elevado de perigo de incêndio quando comparado com a de Porto Alegre. No entanto, para se obter um resultado aceitável de segurança contra incêndio, verifica-se que a área estudada da cidade de Coimbra necessita de intervenções de menor envergadura do que as necessárias para Porto Alegre; isso é explicado pelo tamanho das áreas construídas, já que em Porto Alegre encontram-se edifícios de até vinte e oito andares, enquanto em Coimbra, cinco é o número máximo de pavimentos das construções. / The occurrence of fire in buildings has risen increasingly in Brazil and other countries. To find solutions for this problem, academic groups, fire departments and other authorities responsible for fire safety have realized various studies related of fire prevention and protection, always seeking to enhance existing laws and procedures in this area. However, the laws are still not suitable for old buildings, including virtually all urban centers. Urban Centers, usually old sites, concentrate the largest share of retail trade in the city, which means large numbers of people circulating in these locations. The occurrence of a fire in urban centers can cause various damages and losses associated with both the historical heritage, that is the memory of the city, and to human life, the most severe. Thus, mapping of fire risk studies are being developed in the old buildings of urban centers, in order to diagnose the existing risk and, thus, ways to verify that this risk is smaller and acceptable, aiming its control even before its spreading. This research works with two semi quantitative methods of mapping of fire risk in buildings located in urban centers in the city of Coimbra/Portugal and Porto Alegre/Brazil; these being named method Gretener and FRAME, seeking to quantify risk through constructive, geometric and fire safety analysis. The findings in the two urban centers indicated that the factors of fire safety are low and considered unsuitable for this occupation. The study area of the city of Coimbra got a higher result of fire risk when compared with that of Porto Alegre. However, in order to obtain an acceptable fire safety level, it was observed that the Coimbra study area of needs interventions of smaller scale than is required in Porto Alegre; this is explained by the size of the built areas, as Porto Alegre area has buildings of up to twenty-eight floors, while in Coimbra, five is the maximum number of floors.
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Výuka a zhodnocení znalostí žáků základních škol v oblasti požární ochrany / Educating and evaluation of knowledge pupils primary school in the area of fire protectinLEVÁ, Michaela January 2017 (has links)
According to statistics the number of fires is still very high and the main cause is the negligence of people and underestimating of its danger, so that is right to be concerned with this problems. The solution is to educate people since their early age, e.g. within their school attendance. I decided to choose the theme of my dissertation, which deals with education of students in the area of fire protection. Personally, I would like to find out how the students are trained and educated in this issue and how their knowledge is, that is the chosen aim of the thesis. The goal of this dissertation is to find out the methods of educating and the level of knowledge of the fire protection in elementary schools. To achieve the goal and to complete the research questions I conducted a survey and structured interviews (dialogue). The survey was orientated to students of ninth grade in randomly chosen schools and should check out their knowledge in the problems. The structured interviews were realized with school management and were meant to find out the way or methods of teaching in this issue. The results were put into graphs and charts. In the end the comparison of students´ knowledge was done on two randomly chosen schools, or between two regions of the South Bohemia. The comparison was done within statistical counting methods. After the final evaluation that is possible to say that the knowledge of students in the area of the fire protection is on relatively good level. On the other way around, the methods and extensiveness of education in this area, in view of the fact that importance of fire protection, is in my point of view not sufficient and should have given more attention. In the statistical research it was found out that there are not big differences between the knowledge of students in chosen schools, or regions.
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Aplicação comparativa de métodos de mapeamento de riscos de incêndio nos centros urbanos das cidades de Coimbra e Porto Alegre / Comparative application of methods for mapping fire hazard in urban centers of the cities of Coimbra and Porto AlegreLucena, Renata Batista January 2014 (has links)
As ocorrências de incêndios nas edificações têm aumentado cada vez mais no Brasil e em outros países. Para as soluções deste problema, grupos acadêmicos, corpos de bombeiros e demais autoridades responsáveis pela segurança contra incêndio vêm realizando vários estudos relacionados à prevenção e proteção contra incêndio, buscando sempre aprimorar as legislações e procedimentos já existentes nesta área. Porém, as legislações ainda não são adequadas para os edifícios antigos, incluindo praticamente todos os centros urbanos. Os centros urbanos, geralmente locais antigos, concentram a maior parte dos estabelecimentos de comércios da cidade, o que significa elevado número de pessoas circulando por esses locais. A ocorrência de um incêndio em um centro urbano pode causar vários danos e perdas relacionados, tanto com o patrimônio histórico que representa a memória da cidade, quanto aos relacionados à vida humana, sendo estes os de maior gravidade. Deste modo, estudos de mapeamento de risco de incêndio estão sendo desenvolvidos nas edificações de centros urbanos antigos, com o fim de diagnosticar o risco existente e, com isso, verificar maneiras para que este risco seja menor e aceitável, objetivando o seu controle antes mesmo que se propague. Esta pesquisa trabalha com dois métodos semiquantitativos de mapear risco de incêndio em edifícios localizados nos centros urbanos da cidade de Coimbra/Portugal e Porto Alegre/ Brasil; sendo estes nomeados de Método de Gretener e FRAME, que buscam quantificar o risco através de análises construtivas, geométricas e de segurança contra incêndio. Os resultados do trabalho nos dois centros urbanos indicaram que os fatores de segurança contra incêndio são baixos e considerados inadequados para esta ocupação. A área estudada da Cidade de Coimbra ficou com um resultado mais elevado de perigo de incêndio quando comparado com a de Porto Alegre. No entanto, para se obter um resultado aceitável de segurança contra incêndio, verifica-se que a área estudada da cidade de Coimbra necessita de intervenções de menor envergadura do que as necessárias para Porto Alegre; isso é explicado pelo tamanho das áreas construídas, já que em Porto Alegre encontram-se edifícios de até vinte e oito andares, enquanto em Coimbra, cinco é o número máximo de pavimentos das construções. / The occurrence of fire in buildings has risen increasingly in Brazil and other countries. To find solutions for this problem, academic groups, fire departments and other authorities responsible for fire safety have realized various studies related of fire prevention and protection, always seeking to enhance existing laws and procedures in this area. However, the laws are still not suitable for old buildings, including virtually all urban centers. Urban Centers, usually old sites, concentrate the largest share of retail trade in the city, which means large numbers of people circulating in these locations. The occurrence of a fire in urban centers can cause various damages and losses associated with both the historical heritage, that is the memory of the city, and to human life, the most severe. Thus, mapping of fire risk studies are being developed in the old buildings of urban centers, in order to diagnose the existing risk and, thus, ways to verify that this risk is smaller and acceptable, aiming its control even before its spreading. This research works with two semi quantitative methods of mapping of fire risk in buildings located in urban centers in the city of Coimbra/Portugal and Porto Alegre/Brazil; these being named method Gretener and FRAME, seeking to quantify risk through constructive, geometric and fire safety analysis. The findings in the two urban centers indicated that the factors of fire safety are low and considered unsuitable for this occupation. The study area of the city of Coimbra got a higher result of fire risk when compared with that of Porto Alegre. However, in order to obtain an acceptable fire safety level, it was observed that the Coimbra study area of needs interventions of smaller scale than is required in Porto Alegre; this is explained by the size of the built areas, as Porto Alegre area has buildings of up to twenty-eight floors, while in Coimbra, five is the maximum number of floors.
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Aplicação comparativa de métodos de mapeamento de riscos de incêndio nos centros urbanos das cidades de Coimbra e Porto Alegre / Comparative application of methods for mapping fire hazard in urban centers of the cities of Coimbra and Porto AlegreLucena, Renata Batista January 2014 (has links)
As ocorrências de incêndios nas edificações têm aumentado cada vez mais no Brasil e em outros países. Para as soluções deste problema, grupos acadêmicos, corpos de bombeiros e demais autoridades responsáveis pela segurança contra incêndio vêm realizando vários estudos relacionados à prevenção e proteção contra incêndio, buscando sempre aprimorar as legislações e procedimentos já existentes nesta área. Porém, as legislações ainda não são adequadas para os edifícios antigos, incluindo praticamente todos os centros urbanos. Os centros urbanos, geralmente locais antigos, concentram a maior parte dos estabelecimentos de comércios da cidade, o que significa elevado número de pessoas circulando por esses locais. A ocorrência de um incêndio em um centro urbano pode causar vários danos e perdas relacionados, tanto com o patrimônio histórico que representa a memória da cidade, quanto aos relacionados à vida humana, sendo estes os de maior gravidade. Deste modo, estudos de mapeamento de risco de incêndio estão sendo desenvolvidos nas edificações de centros urbanos antigos, com o fim de diagnosticar o risco existente e, com isso, verificar maneiras para que este risco seja menor e aceitável, objetivando o seu controle antes mesmo que se propague. Esta pesquisa trabalha com dois métodos semiquantitativos de mapear risco de incêndio em edifícios localizados nos centros urbanos da cidade de Coimbra/Portugal e Porto Alegre/ Brasil; sendo estes nomeados de Método de Gretener e FRAME, que buscam quantificar o risco através de análises construtivas, geométricas e de segurança contra incêndio. Os resultados do trabalho nos dois centros urbanos indicaram que os fatores de segurança contra incêndio são baixos e considerados inadequados para esta ocupação. A área estudada da Cidade de Coimbra ficou com um resultado mais elevado de perigo de incêndio quando comparado com a de Porto Alegre. No entanto, para se obter um resultado aceitável de segurança contra incêndio, verifica-se que a área estudada da cidade de Coimbra necessita de intervenções de menor envergadura do que as necessárias para Porto Alegre; isso é explicado pelo tamanho das áreas construídas, já que em Porto Alegre encontram-se edifícios de até vinte e oito andares, enquanto em Coimbra, cinco é o número máximo de pavimentos das construções. / The occurrence of fire in buildings has risen increasingly in Brazil and other countries. To find solutions for this problem, academic groups, fire departments and other authorities responsible for fire safety have realized various studies related of fire prevention and protection, always seeking to enhance existing laws and procedures in this area. However, the laws are still not suitable for old buildings, including virtually all urban centers. Urban Centers, usually old sites, concentrate the largest share of retail trade in the city, which means large numbers of people circulating in these locations. The occurrence of a fire in urban centers can cause various damages and losses associated with both the historical heritage, that is the memory of the city, and to human life, the most severe. Thus, mapping of fire risk studies are being developed in the old buildings of urban centers, in order to diagnose the existing risk and, thus, ways to verify that this risk is smaller and acceptable, aiming its control even before its spreading. This research works with two semi quantitative methods of mapping of fire risk in buildings located in urban centers in the city of Coimbra/Portugal and Porto Alegre/Brazil; these being named method Gretener and FRAME, seeking to quantify risk through constructive, geometric and fire safety analysis. The findings in the two urban centers indicated that the factors of fire safety are low and considered unsuitable for this occupation. The study area of the city of Coimbra got a higher result of fire risk when compared with that of Porto Alegre. However, in order to obtain an acceptable fire safety level, it was observed that the Coimbra study area of needs interventions of smaller scale than is required in Porto Alegre; this is explained by the size of the built areas, as Porto Alegre area has buildings of up to twenty-eight floors, while in Coimbra, five is the maximum number of floors.
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Stratification thermique et optique d'un environnement enfumé et interactions eau/fumée sous aspersion / Experimental and Numerical Study of Smoke/Mist Interactions Related to Heat Transfer and Optical Properties in a CorridorMorlon, Romain 02 October 2015 (has links)
Ce travail est consacré à l'étude des interactions eau/fumée dans un couloir, lors du déclenchement d'un système d'aspersion dans un environnement enfumé. Il s'attache à évaluer les effets thermiques et optiques induits par une pulvérisation d'eau par sprinkler et par brouillard d'eau sur une couche de fumée générée à partir d'un foyer type bac d'heptane. Une synthèse bibliographique permet de faire l'état des travaux concernant la recherche sur l'aspersion d'eau pour le contrôle du feu lors d'un incendie en bâtiment et sur les notions de stratification des fumées. Une étude expérimentale basée sur 50 essais en grandeur réelle est présentée, impliquant des mesures thermiques et optiques. Un système d'opacimétrie laser spécifique a notamment été développé, permettant de mesurer l'opacité des fumées et les effets des interactions eau/fumée sur l'opacité et la visibilité. La partie numérique s'appuie sur le code FDS version 6 (Fire Dynamics Simulator) pour la simulation des essais et sur un module spécifique consacré à l'évaluation de la visibilité en parallèle. Utilisant les valeur extraites de la simulation par FDS pour les concentrations en gouttes et en suie, ce code calcule les propriétés optiques du milieu absorbant-diffusant considéré, puis combine une méthode de Monte-Carlo et des techniques de PSF (Point Spread Function) et MTF (Modulation Transfer Function) pour évaluer l'intensité et le contraste d'images reconstruites. Les effets de déstratification thermique et optique sont comparés pour chaque technologie d'aspersion expérimentalement et numériquement. / This work was devoted to the study of water/smoke interactions in the case of water mist activation on a smoke layer. The aim was to investigate the effects observed on thermal and optical properties when injecting water particles using sprinkler or water mist devices through a smoke layer generated with an heptane pool fire. A first review was reported in order to highlight the researches devoted to water aspersion for firefighting and the smoke stratification phenomena. An experimental study based on 50 runs at real scale was presented, involving optical and thermal measurements. In particular, a laser opacimeter system was developed, which allowed measuring the smoke opacity and the effects of smoke/water interactions on opacity and visibility. Afterwards, a numerical study was conducted. On the one hand fire tests were simulated using the FDS 6th version (Fire Dynamics Simulator) and on the other hand a dedicated code allowed us to evaluate the visibility. The values of the soot and droplet concentrations were extracted from FDS and used into the code dedicated to visibility to calculate the optical properties of the corresponding absorbing-scattering environment. Those properties are then used in a Monte Carlo approach combined with PSF (Point Spread Function) and MTF (Modulation Transfer Function) methods to evaluate the intensity and the contrast of reconstructed images. The destratification effects based on thermal and optical criteria were compared experimentally and numerically for each technology.
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Kapalné elektrolyty pro lithno-iontové akumulátory s vyšší požární bezpečností / Liquid Electrolytes for Lithium-Ion Batteries with Enhance Fire SafetyMáca, Josef January 2018 (has links)
Dissertation thesis is focused on study of liquid electrolytes for lithium ion batteries. The electrical and physical properties of aprotic electrolytes are observed. The main goal is to increase the fire safety of the batteries. An anhydrous solvents and there blends was investigated. The common used solvents mixtures and new low flammable solvents were used. The common used solvents were used propylene carbonate, ethylene carbonate and others. The new solvents were sulfolane and dimethyl sulfone. In the second part of the work the phosphor base flame retardants as additive in electrolytes was investigated. The last part deals with ionic liquids and there possible use as electrolyte in lithium ion batteries.
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Etudes Expérimentales et lois prédictives des foyers d'incendies / Experimental studies and predictive laws for fire sourcesBetting, Benjamin 21 September 2018 (has links)
Chaque année en France, les feux de compartiments donnent lieu à plus de 88 000 interventions impliquant plus de 15 000 personnes dont plusieurs centaines de décès et de blessés graves. Aujourd’hui, lors de ces feux, les prises de décision et les délais d’intervention des équipes de secours sont principalement basés sur des décisions humaines, fruits de l'expérience. Une connaissance parfaite de la situation, de son évolution dans le temps et des dangers qui peuvent apparaître est impossible. C’est en partie la cause majeure des mauvais chiffres répertoriés ci-dessus. En effet, les processus physicochimiques qui régissent les feux de compartiments et les situations collatérales extrêmement réactives et dangereuses sont complexes. La transition entre un feu localisé et un feu généralisé peut prendre plusieurs formes. L'un des vecteurs les plus importants dans la propagation de la combustion pour les feux de compartiments sont les fumées, du fait de leur température élevée (souvent supérieure à 600°C) et des quantités importantes d’énergie, sous forme de chaleur, qu'elles contiennent. Malgré leur extrême dangerosité, les fumées restent importantes à étudier car elles véhiculent de précieuses informations, notamment sur l’apparition de phénomènes thermiques redoutés par les pompiers. Afin de mener cette étude, une cellule expérimentale composé de deux containers maritimes a été installée sur le site de formation incendie des sapeurs-pompiers de Seine-Maritime. Cette plateforme va permettre, grâce à un brûleur alimenté en propane, de produire des fumées chaudes dans uneconfiguration dite « feu réel ». Elles seront analysées en partie grâce à une technique de mesure non intrusive, la PIV. Les mesures par PIV grands champs seront comparées à des simulations LES de l’expérience (FDS). La double compétence (numérique / expérimentale) est essentielle dans ce type d’étude où les données expérimentales souffrent d’un manque de résolution (spatiale et temporelle) mais pour autant représentent des informations nécessaires à la validation des codes. / Each year in France, compartment fires result in more than 88,000 interventions involving more than 15,000 people, including several hundred deaths and serious injuries. Today, during fire compartments, the decision-making of the rescue teams is mainly based on human decisions, as a result of the accumulated experience. However, a perfect knowledge of the situation, its evolution over time and the dangers that may appear is impossible. Therefore, studying the fumes is of major interest. Indeed, smoke remains important to study because it conveys valuable information, especially on the appearance of thermal phenomena feared by firemen. In order to carry out this study, an experimental cell made up of two maritime containers was installed on the site of the Seine-Maritime fire brigade fire training. This platform will produce hot smokes in a configuration called "real fire" thanks to a propane burner. In this study, the smoke dynamics in a large scale experimental setup is analyzed using a non-intrusive measurement technique such as PIV (Particle Image Velocity). All the performed measurements are compared with LES (Large Eddy Simulation) simulations of the experiment using Fire Dynamics Simulator (FDS). The double expertise (numerical / experimental) is essential in this type of study where the experimental data suffer from a lack of resolution (spatial and temporal) but nevertheless represents an important source of information necessary for the validation of the codes.
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Boendesprinkler : Hur ska boendesprinkler projekteras och installeras för att undvika vattenskador och tillväxt av legionella? / Residental sprinklers : How should residental sprinklers be designed and installed in order to avoid water damage and legionella growth?Mohammadi, Adam, Asp, Hampus January 2013 (has links)
Rapporten är sammanställd av två kandidatstudenter vid Kungliga tekniska högskolan på högskoleingenjörsprogrammet Byggteknik och design, i samarbete med Säker Vatten AB. Efter tre års studier är detta en examinerande rapport för utbildningen. Rapporten är ämnad för alla typer av läsare, men utan byggingenjörsexamen likt vår, eller med motsvarande kunskapsnivå så kan läsare uppfatta rapporten som svårläst. Metoden för rapporten har varit så att författarna kontinuerligt intervjuat aktörer med olika intressen för hur branschen utvecklar sig. Aktörerna i fråga har alla mångårig erfarenhet eller en relevant utbildning bakom sig. Litteraturstudier har gjorts av föreskrifter, standarder, normer och rapporter som behandlar boendesprinkler, rörförläggningar, legionella och vattenskador. Tolkningar och utförande av detta baseras på kunskap som införskaffats som ingenjörsstudenter under utbildningens gång, allt för att så nyanserat som möjligt närma sig svaret på rapportens problemformulering: ”Hur ska boendesprinkler projekteras och installeras för att undvika vattenskador och tillväxt av legionella?” Som huvudsyfte har arbetet inneburit att fokusera på problemformuleringen. Problemformuleringen har i sin tur fördelats i tre frågor där varje fråga berört olika verksamheter och organisationer i branschen. Frågan specificerar vattenskadorna som kan uppkomma i samband med boendesprinkler. För att besvara den frågan har relevanta avsnitt i BBR, standarden SS 883001 samt branschregler Säker Vatteninstallation studerats. Frågan hanterar tillväxten av legionella i boendesprinkleranläggningar. Här har myndigheter och branschorganisationer såsom Smittskyddsinstitutet, Svenskt vatten och Stockholm Vatten varit till stor hjälp. Frågan har behandlat vilka krav som ställs på de som projekterar och installerar boendesprinkler idag. Utgångspunkten för fråga tre har varit normer från Svenska Brandskyddsföreningen som behandlar boendesprinkler, samt VVS-Företagens och Sprinklergruppens utbildning för sprinklermontörer. Förhoppningen är att den här rapporten ska fungera som underlag för skrivande av branschregler för projektering och installation av boendesprinkler. Branschregler som säkerställer att vattenskador och tillväxt av legionella undviks. Med korrekta branschregler så bör förståelsen för boendesprinkler och dess effekt öka. Antalet boendesprinkleranläggningar bör då också öka, vilket skulle resultera i ett mer brandsäkert Sverige. / The report was compiled by two graduate students at the Royal Institute of Technology, Bachelor of Science program Constructional Engineering and Design, in collaboration with Säker Vatten AB. After three years of study, this is a graded report for our education. This report is intended for all types of readers, but without education like ours, or equivalent level of knowledge, the report may be difficult to understand. The methodology for this report is that the authors continually interviewing actors with different interests in how the industry develops. The players in question all have many years of experience or relevant training behind. Studies of literature have been made of regulations, codes, standards, and reports dealing with residential sprinklers pipe laying, legionella and water damage. Interpretations and execution of this is based on the knowledge acquired as engineering students during their education, all to approach an answer so nuanced as possible to the problem report:" How should residential sprinklers be designed and installed in order to avoid water damage and legionella growth?” As the main work has meant to focus on the problem statement, which in turn is divided into three questions, each question touched on various businesses and organizations in the industry. This question specifies the water damage which may arise in connection with residential sprinklers. To answer that question, the relevant section of BBR, the standard SS 883001, as well as industry regulations plumbing safety studied. This question handles the growth of legionella in residential sprinklers. Here are authorities and industry organizations such as the Infectious Diseases Institute, Swedish Water and Stockholm Water were a great help. This question has dealt with the demands placed on the projecting and installing of residential sprinklers today. The starting point for question number three were standards from Swedish Fire Protection Association which deals with residential sprinklers, and training for installers of sprinkler. This report will hopefully serve as a basis for the writing of industry regulations for design and installation of residential sprinklers. Industry regulations which will ensure that water damage and the growth of Legionella will be avoided. With proper industry regulations will the understanding of residential sprinklers and its effect increase. The number of residential sprinkler installations should then also increase, which would result in a more fireproof Sweden.
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En litteratur- och intervjustudie om ansvaret för ett tillfredställande brandskydd hos de med Avancerad Sjukvård i Hemmet, ASiH.Norbäck, Emma, Eriksson, Molly January 2022 (has links)
No description available.
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Brandteknisk dimensionering av KL-trä – Jämförelse av nuvarande Eurokod 5 och kommande version / Fire safety design of CLT – Comparison of present Eurocode 5 and upcoming editionKarlsson, Emil, Hama Jan, Gelan January 2023 (has links)
Bygg- och fastighetssektorn är en bidragande faktor till växande koldioxidutsläpp och det krävs därför klimatbaserade innovationer för att arbeta mot ett hållbart och långsiktigt samhälle. På senare år har råvaran trä använts i form av KL-trä som konstruktionsmaterial i allt fler och större byggnader. Parallellt med utvecklingen av KL-trä har även en strävan att behålla materialet oskyddat och synligt växt fram. För att möta kraven på brandsäkerhet i konstruktioner av KL-trä, arbetas nya dimensioneringsregler fram. I detta arbete studeras hur bärförmågan vid brand i nuvarande Eurokod 5 EN 1995-1-2:2004 och kommande version prEN 1995-1-2:2025 dimensioneras hos konstruktioner av KL-trä med synliga ytor. Syftet med arbetet är att ta fram skillnader och likheter mellan respektive version, samt vilken inverkan de kan få. Målet med arbetet är klargöra hur branddimensionering kommer påverkas och på så sätt kunna vara ett underlag för vidare studier och användning inom området. Dimensionering görs på vägg- och bjälklagselement med uppbyggnad av 5 st 40 mm lameller respektive 7 st 20 mm lameller för båda elementen. Dimensionerande brandexponeringstid som beaktas är 60 minuter, men även 90 minuter för väggelementen som krävs för att byggnader med mer än åtta våningar. Beräkningar och jämförelser görs på element av olika uppbyggnader för att tydliggöra relationen mellan typen av lim och bärförmågan. KL-träelement med icke brandtåligt lim uppvisar lägre bärförmågor än element med brandtåligt lim. Detta stämmer särskilt vid element med uppbyggnader av tunnare lameller. Orsaken till detta är att icke brandtåligt lim ger upphov till delaminering som minskar det effektiva tvärsnittet på grund av en ökad förkolningshastighet. Delamineringen ger även upphov till värmeökning då det sker en ny övertändning. Beräkningar visar att det är fördelaktigt med en tjockare yttre lamell för att minska risken för delaminering under brandexponeringstid 60 minuter och 90 minuter. Resultaten jämförs också med resultat från avancerade beräkningsmetoder i de fall där korrekta underlag fanns tillgängligt. Vid framtagning av det icke lastupptagande skiktet enligt kommande version påvisas markant skillnad jämfört med den nuvarande versionen. Enligt kommande version tas det hänsyn till aspekter som tvärsnittshöjd, lamelltjocklek, lamellriktning, om ytan är initialt skyddat eller ej, om den brandexponerade sidan utsätts för tryck- eller dragspänningar m. m. Utöver det tillkommer vissa eventuella avdrag på det resterande tvärsnittet beroende på vart det icke lastupptagande skiktet befinner sig. Nuvarande version anger alltid det icke lastupptagande skiktet som 7 mm. Framtagning av bärförmågan i den kommande versionen bygger likt den nuvarande versionen på den effektiva tvärsnittsmetoden. Det som däremot skiljer versionerna åt är förkolningsdjupet, samt införandet av ny metod för framtagning av det icke lastupptagande skiktet, som nämnt ovan. I kommande version har beräkningsgången för dessa delar uppdaterats och därmed beaktas även fler parametrar som icke brandtåligt lim. Förkolningsdjupet för kommande version beräknas enligt den europeiska förkolningsmodellen som beror på limtyp. Då endast brandtåligt lim beaktas i EN 1995-1-2:2004 bör en direkt tillämpning på KL-trä göras med försiktighet. Arbetet lyfter även fram generella konsekvenser för synligt KL-trä vid brandexponering. / The construction and property sector is a contributing factor to growing emissions of carbon dioxide and climate-based innovations are therefore required to work towards a sustainable and long-term society. In recent years, the raw material wood has been used in form of CLT (Cross Laminated Timber) as a construction material in an increasing number of buildings. Along the development of CLT, the desire to keep the material unprotected and visible has also grown. To meet the requirements for fire safety in CLT-buildings, new design standards are under development. In this study, the firedesign method and results of load-bearing elements of CLT with visible surfaces are compared between the current Eurocode 5 EN 1995-1-2:2004 and the upcoming version prEN 1995-1-2:2025. The purpose of the work is to highlight the differences and similarities between the two versions, and in that way provide basis for future studies and usages. Firedesign is calculated on wall and floor elements with a structure of 5 and 7 laminates respectively for both elements. The fire exposure time considered is 60 minutes, but also 90 minutes for the wall elements which is to clarify the relationship between the type of adhesive and the load-bearing capacity. The fire exposure time considered is 60 minutes, but also 90 minutes for the wall elements which is required for buildings with more than four stories, according to the Swedish building code BBR and to clarify the relationship between the type of adhesive and the load-bearing capacity. CLT elements with non-fire-resistant adhesive have lower load-bearing capacities than elements with fire-resistant adhesive. Calculations according to the upcoming version contains more parameters like non-fire-resistant adhesive and a more complex non-load-capacity layer, which are deficient in the current Eurocode. Since non-fire-resistant adhesive are not included in EN 1995-1-2:2004, a direct application on CLT should be done with caution. The study also highlights general consequences when using visible CLT in buildings.
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