Dissertations / Theses: 'Fire load'

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SOLTANI, GHULAM H. "BUCKLING AND POST-BUCKLING RESPOSNE OF SINGLE CURVATUE BEAM-COLUMNS UNDER THERMAL (FIRE) LOADS." OpenSIUC, 2017. https://opensiuc.lib.siu.edu/theses/2147.

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The main objective of this research was to study the buckling and post-buckling response of axially restrained beam-columns under thermal loading. Also the effects of slenderness ratios on pre-buckling and post-buckling behavior which is neglected in AISC specification was examined. The results of this study indicate that: a) Both the deflection and end moment amplification factors are significantly smaller for the restrained beam-columns subjected to temperature increase than the corresponding unrestrained beam-columns subjected to (mechanical) axial loads. b) The deflection amplification factors tend to decrease with decreasing ratio of end moments. However, reverse seems to occur for the moment amplification factors and as the moment amplification factors tend to increase with decreasing moment ratio particularly in the pre-buckling and the initial post-buckling range (0.1 < T/Tcr < 1.5). c) The thermal amplification factors tend to be smaller than the AISC values even in the pre-buckling range with those for the slender beam-columns significantly smaller than those for the shorter beam-columns.

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Ferreira, Michael J. "Barrier Performance Utilizing Normalized Heat Load as Part of an Engineering Based Building Fire Protection Analysis Method." Digital WPI, 2004. https://digitalcommons.wpi.edu/etd-theses/1074.

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"The objective of this thesis is to examine the methods of barrier analysis used in the Building Fire Safety Engineering Method (BFSEM), and to develop the areas of the analysis which currently rely almost exclusively on subjective judgment rather than quantitative measures. The use of the Normalized Heat Load to quantify heat energy impact on a barrier is examined in detail. Procedures are developed which apply the properties of a normal statistical distribution to barrier failures times, for use in simplifying the construction of barrier catalog curves. A framework is also developed to help standardize the selection of barrier effectiveness factors. Finally, this thesis outlines the procedure for developing barrier performance curves to allow easy implementation of the barrier analysis into the general framework of the BFSEM. A design example is presented to illustrate the analysis procedures."

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Lilja, Andreas. "Temperature analysis of fire exposed load-bearing structures of mono glazed balconies." Thesis, Luleå tekniska universitet, Byggkonstruktion och brand, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-81730.

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Previous to the now acting construction regulations EKS and Eurocode, the fire resistance of the load-bearing structures of mono glazed balconies were designed with a fire test called the SP fire 105. In 2011, when EKS replaced the previous construction regulations called Boverkets konstruktionsregler, BKR, the SP fire 105 was no longer the requirement for mono glazed balconies. Instead, EKS prescribed that the load-bearing structures of mono glazed balconies should be determined by the use of nominal fire exposure or a natural fire model. EKS and Eurocode have previously prescribed that the standard temperature-time curve (ISO 834) was to be used when determining the fire resistance of structural elements according to nominal temperature-time curves. But an agreement made between Balkongföreningen and Boverket in 2011, established that the external temperature-time curve could be used for determination of the fire resistance of the structural elements of mono glazed balconies. The external temperature-time curve means a design temperature of the structural members of approximately 680 °C for a fire-resistance class R30, instead of a temperature of 842 °C for the standard temperature-time curve. In 2019, EKS 11 was introduced with a slight change in the regulation. The new regulation specifically implies that building parts placed within glazed balconies should not be considered as external. Due to the formulation in EKS 11, it is no longer possible to use the external temperature-time curve for verification of the fire resistance of structural elements of mono glazed balconies. The formulation says that building parts placed within glazed balconies should not be considered as external, which means that the standard temperature-time curve must be applied. The present research tries to clarify the more reasonable temperature-time curve of the standard fire curve and the external fire curve, or if neither of the curves is realistic. 16 scenarios were analysed in this study. Using CFD simulations in FDS, the adiabatic surface temperature of the structural parts could be established. The adiabatic surface temperatures were then used as input in the FEM calculation program TASEF to calculate the temperatures of structural elements of a mono glazed balcony during a fire. The results imply that the max temperatures of the steel members of the mono glazed balcony analysed are generally lower than the temperatures of the external temperature-time curve. In a worst-case scenario where the structural member is located just adjacent to the fire source, the max temperature can be higher than the temperature of the standard temperature-time curve. The balcony slab reaches max temperatures between the external temperature-time curve and the standard temperature-time curve. The temperature within the slab is below 500 °C at a depth of 15 mm and according to the 500 °C isotherm method presented in SS-EN 1992-1-2, concrete that has a temperature lower than 500 °C has not been damaged by the fire. Further studies are needed to establish whether the external temperature-time curve or the standard temperature-time curve is to be used when designing the fire resistance of the load-bearing structure of mono glazed balconies. A suggestion for further studies is to conduct fire tests of a fire within a mono glazed balcony. Such results could then be compared to the results of this study and hopefully, lead to conclusions that are needed for a complete establishment of which temperature-time curve that should be used.
Under det tidigare gällande regelverket boverkets konstruktionsregler, BKR, dimensionerades brandmotståndet för den bärande konstruktionen av enkelinglasade balkonger med testmetoden SP fire 105. När BKR ersattes av boverkets föreskrifter och allmänna råd om tillämpning av europeiska konstruktionsstandarder, EKS, tillsammans med Eurokoderna, slutade man att använda SP fire 105 och började istället använda nominella temperatur-/tidförlopp. I tidigare versioner av EKS föreskrevs det att dimensionering enligt klassificering ska utföras med en brandexponering enligt standardtemperatur/-tidkurvan (ISO 834). Men i och med upphörandet av BKR år 2011, genomfördes en överenskommelse mellan Balkongförening och Boverket där man bestämde att den bärande konstruktionen för enkelinglasade balkonger och öppna balkonger skulle få dimensioneras med exponeringskurvan för utvändig brand istället för standardtemperatur-/tidkurvan. Dimensionering enligt exponeringskurvan för utvändig brand resulterar i en dimensionerande temperatur på 680 °C för brandteknisk klass R30, istället för en temperatur på 842 °C vid dimensionering med standardtemperatur-/tidkurvan. Vid införandet av EKS 11 år 2019 skedde en förändring i föreskrifterna gällande branddimensionering av bärande konstruktioner. I EKS 11 framgår det explicit att byggnadsdelar vilka är placerade inom inglasade balkonger inte bör betraktas som utvändiga byggnadsdelar. Detta medför att den bärande konstruktionen för enkelinglasade balkonger inte längre kan dimensioneras enligt exponeringskurvan för utvändig brand, utan måste dimensioneras enligt standardtemperatur-/tidkurvan. Denna studie syftar till att klargöra vilken temperatur som är rimlig att använda vid dimensionering av den bärande konstruktionen för enkelinglasade balkonger. Är den tidigare exponeringskurvan för utvändig brand mer rimlig, eller är föreskriften om att använda standardtemperatur-/tidkurvan motiverad? I studien har 16 scenarion analyserats med hjälp av CFD beräkningar i simuleringsprogrammet FDS, och med hjälp av FEM beräkningar i simuleringsprogrammet TASEF. Med FDS beräknades den adiabatiska yttemperaturen för den bärande konstruktionen, vilken sedan användes som indata i TASEF för att beräkna temperaturen i den bärande konstruktionen. Maxtemperaturen på konstruktionselementen som utgörs av stål uppnår generellt temperaturer som understiger temperaturen för exponeringskurvan vid utvändig brand. I ett ”worst-case” scenario där brandkällan står i direkt anslutning till en stålkonstruktion, kan temperaturer uppnås vilka överstiger temperaturen i standardtemperatur-/tidkurvan. Maxtemperaturen på balkongplattan är högre än temperaturen i exponeringskurvan vid utvändig brand, men lägre än temperaturen i standardtemperatur-/tidkurvan. 15 mm in i balkongplattan understiger temperaturen på betongen 500 °C. Enligt 500 °C isotermmetoden som är publicerad i SS-EN 1992-1-2 innebär detta förenklat att all betong på ett djup överstigande 15 mm har kvar sin fulla bärförmåga. En slutsats är att det krävs vidare studier för att kunna fastställa vilket nominellt temperatur-/tidförlopp som borde användas vid dimensionering av den bärande konstruktionen för enkelinglasade balkonger. Ett förslag på vidare studier är att utföra brandtester på en enkelinglasad balkong, varav resultaten sedan kan jämföras med resultaten i denna studie. Sådana resultat skulle förhoppningsvis möjliggöra ett fastställande av vilket nominellt temperatur-/tidförlopp som bör användas vid dimensionering av den bärande konstruktionen för enkelinglasade balkonger.

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Bregulla, Julie. "Investigation into the fire and racking behaviour of structural sandwich panel walls : a methodology to assess load bearing sandwich panels in fire." Thesis, University of Surrey, 2003. http://epubs.surrey.ac.uk/807/.

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Stanton, Rebekah L. "Fire and Rodent Consumer Effects on Plant Community Assembly and Invasion in North American Deserts." BYU ScholarsArchive, 2021. https://scholarsarchive.byu.edu/etd/9172.

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This dissertation explores the differential effects of fires and rodent communities on native and invasive desert plant communities. Chapter one examines the impacts of fire and repeat fires on fuel loads in two different Utah desert sites, one in the cool Great Basin Desert and one in the hyper-arid Mojave Desert, over the course of four years. We found that both desert sites responded with varying intensities to a single burn, but the effects of a reburn were not as pronounced. We also found that our Great Basin Desert site had a stronger response to fire than our Mojave Desert site, producing a higher plant fuel loads that could potentially exacerbate the changing fire regimes. These data can be used to help map the effects that climate change may have on fuel loads and the fire potential of these deserts. Chapter two uses a full factorial experimental design to compare the effects of rodent herbivory and fire on native versus invasive seedlings at our Mojave Desert field site. We found that rodent herbivory has a more negative impact on the survival of native seedlings than invasive seedlings. This could be because the invasives are grasses that tend to tolerate herbivory better than the native shrubs and forbs. Chapter three again uses a full factorial experimental design to assess the impacts of rodents and fire on the fate of native and invasive seeds at our field site in the Mojave Desert. We found that rodents removed seeds, and they did show preferences for some species of seed over others, but these preferences were not different between native and invasive seeds or seed mass. We propose that the preferences may be influenced by other seed traits such as water content, handling time or physical and chemical defenses. As with the seedlings in chapter two, fire did not have any impact on rodent seed preferences. These data highlight the importance of considering rodent effects on seeds used in restoration effects following wildfires.

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Andersson, Anna, and Eva-Sara Carlson. "Structures in underground facilities : Analysis of a Concrete Column’s Capacity to Withstand Extraordinary Fire Loads." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-18114.

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The report present a Master of Science in engineering work carried out at Mälardalen’s University, made this work within the research project METRO. The work is a part of the research project METRO. The focus of the METRO project is on the protection of underground rail mass transport systems e.g. tunnels and subways stations. The aim with this work was to determine if a concrete column placed close to the tracks at a subway station can withstand the effect and temperature of a fire in a burning train comparable to the effects and temperatures that showed at the full scale test carried out within the METRO project. A literature review was made previous to the following case study. The results from this show that the column is negligible affected by the fire.
METRO project 2009-2012

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Graham, Earl Vincent. "Developing a remotely-sensed framework for fire monitoring in the Western Cape, South Africa." University of Western Cape, 2021. http://hdl.handle.net/11394/8334.

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>Magister Scientiae - MSc
For a long time, fire dynamics has been misunderstood and viewed as either a destructive force or an ecological necessity. The Western Cape Province in South Africa experiences the frequent occurrence of fires, due to the prevailing Mediterranean climatic conditions. This climate is known for its hot and dry summers and its cold and wet winters, which, along with the highly flammable indigenous flora of the Western Cape, provide suitable conditions for the occurrence of fires. However, the local environmental and ecological variables that influence the occurrence of fires and that could assist with fire management practices remain poorly understood. The development of an integrated operational monitoring framework is therefore imperative for detecting and mapping the occurrence of fires in the Western Cape, South Africa.

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Kayili, Serkan. "Effect Of Vehicles&#039." Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12611290/index.pdf.

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Road and railways tunnels are constructed for decreasing the transportation time inside city or intercity. The fire safety systems are mounted for the safe use of tunnels. Therefore, it is important to accurately predict the fire-induced air velocity,temperature and smoke concentrations in tunnel fires in order to design efficient fire protection systems. To this end, scaled tunnel models are used and experiments are carried to understand the phenomena on these tunnel models. In addition, the studies for investigating the tunnel fire phenomena and their methods of modeling techniques for fire experiments are mentioned. In the literature, there is no sufficient information about vehicles'
blockage effect on heat release rate and temperature distribution inside tunnel with different ventilation velocities. As a result, in order to research this subject, the scaled model tunnel is constructed in Fluid Mechanics Laboratory. Based on the Froude number scaling, wood sticks with different configuration inside the model tunnel are burned in a controlled environment. The heat release rate measurement, sampling of gases after combustion, mass loss rate of burning models and temperature distribution along the tunnels with different longitudinal ventilation velocities are measured to investigate the effect of different cross-sectional areas of the burning substances. Furthermore, the model vehicles having a square base area are built according to wood crib theory. The results are investigated with statistical techniques called "
Analysis of Variance"
and general results have been tried to be reached. It is determined that the variation of air velocity inside tunnel is not so effective, but model vehicle'
s cross sectional area is directly proportional to heat release rate.

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Le, Phung Van. "Assessment of Fire Safety for Intermediate Floors in the New Zealand Acceptable Solution C/AS1." Thesis, University of Canterbury. Civil and Natural Resources Engineering, 2010. http://hdl.handle.net/10092/3942.

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This research project aims to investigate the level of risk/safety inherent in intermediate floors of buildings designed to the Compliance Document for the New Zealand Building Code, Fire Safety Clauses C1, C2, C3, C4 (C/AS1), and develop guidance for Fire Engineers on designing fire safety for firecells containing intermediate floors. The project also aims to develop a new set of prescriptive fire safety requirements for intermediate floors and proposes an outline of a verification method for designing fire safety for intermediate floors. This study includes a literature review of the fire safety requirements for intermediate floors (mezzanines) of prescriptive requirements in New Zealand and other countries such as USA, Canada, UK and Australia. The results of this literature review found that the intermediate floor size is limited and varies with country. An intermediate floor that has an area exceeding the limit set out by the prescriptive requirements is considered as a storey in all the countries prescriptive requirements reviewed including the New Zealand prescriptive requirements prior to 1991. Since 1991, in New Zealand Acceptable Solutions, the intermediate floor that has an area exceeding the limit will not be treated as a storey, however, a smoke control system is required. The level of risk was quantified using a factor of safety (FoS) - the ratio of Available Safe Egress Time (ASET) to Required Safe Egress Time (RSET). Two fire models; BRANZFIRE and FDS were used to calculate ASET and SIMULEX, an evacuation program, was used to calculate movement times of the occupants of the studied buildings. Unlike the traditional method in which RSET and FoS are assessed using single value, in this project the distribution of RSET and FoS were assessed using the @RISK software package. The analysis showed that the level of risk to the occupants of the firecells containing intermediate floors is always higher than that of the equivalent firecells without intermediate floors with the same occupant load and the differences in FoS range from 10% to 60%. The analysis also highlighted that the level of risk to the occupants of firecells having intermediate floors increases as the intermediate floor size increases, however, there are no clear cut-off points at which a higher level of fire safety precaution should be provided. The cut-off points in C/AS1 of 20% for a closed intermediate floor and 40% for an open intermediate floor, are not justified by this analysis. Occupant load has significant impact on the level of safety of the occupants of the firecells containing intermediate floors. The higher the occupant load the lower the level of safety is. The definitions for open and closed intermediate floors are proposed to which open and closed intermediate floors are clearly distinguished. The term “limited area intermediate floor” in the current C/AS1 is proposed be removed and all related clauses are proposed to be amended or deleted accordingly. A proposed new set of prescriptive fire safety requirements for intermediate floors has been developed based on the occupant load of intermediate floors and not the intermediate floor size in the form of a table similar to the current Table 4.1 of C/AS1. The occupant load and fire safety precautions (FSPs) of the intermediate floors are determined based on the occupant load and their required FSPs of the equivalent firecells without intermediate floors that have the same factor of safety with the firecells containing intermediate floors. With the proposed FSPs, a firecell with lower occupant load would require lesser fire safety requirements than a firecell with higher occupant load regardless of intermediate floor size. Moreover, with the proposed FSPs for intermediate floors, the level of safety of the occupants of the firecells having intermediate floors would be very similar to the level of safety of the equivalent firecells without intermediate floors. In addition to the proposed tables of FSPs, some clauses regarding the changes in the fire safety requirement and definitions for intermediate floors are proposed. Guidance for designers in designing fire safety for firecells containing intermediate floors in which the methods of modelling using BRANZFIRE and Fire Dynamics Simulator (FDS) are presented in detail, has been developed. The analysis has pointed out that the location of the exits is critical in designing fire safety for firecells containing intermediate floors and majority of exits from the lower floor should not be located under intermediate floors. Although one of the main objectives of this research project was to propose an outline of a verification method for designing fire safety for intermediate floors, the analysis showed that it is very difficult to develop a rational verification method for designing fire safety for firecells containing intermediate floors. Using the proposed FSPs for intermediate floors which are based on the occupant load of the intermediate floors in designing fire safety for firecells containing intermediate floors is recommended by this study. These recommendations do not preclude the use of specific fire engineering design for designing fire safety for firecells having intermediate floors.

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Öhrling, Emil. "Brandrisker i däckhotell : Är samhällets krav på byggnadstekniskt brandskydd tillräckligt?" Thesis, Luleå tekniska universitet, Byggkonstruktion och brand, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-83256.

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Syftet med studien är att undersöka de risker som finns i samband med brand i däckhotell, samt utvärdera om samhällets krav på byggnadstekniskt brandskydd är tillräckligt för att hantera risknivån. Samhällets krav i studien är Boverkets byggregler BFS 2011:6 med ändring till och med BFS 2020:4 (BBR) och den kravställning som sker i enlighet med förenklad dimensionering. Kraven i BBR har kvantifierats för att möjliggöra en jämförelse mellan BBR och de verkliga förutsättningar som återfinns på däckhotell. Studien behandlar enbart tre av de fem punkter som BBR baseras på. Utveckling och spridning av brand och rök inom byggnadsverket ska begränsas, spridning av brand till närliggande byggnadsverk ska begränsas och hänsyn ska tas till räddningsmanskapets säkerhet vid brand. Det finns erfarenheter kring bränder i däcklager men ingen samlad bild av hur däckhotell bör hanteras i regelverken, eller om det är förenligt med byggreglernas intention och räddningstjänstens praktiska erfarenheter att utföra insats. Hur ska då brandskyddet utformas i däckhotell för att samhällets krav ska vara uppfyllt? I ett däcklager kan det handla om flera tusen däck som lagras samtidigt. Metodval för att besvara frågeställningarna var att utifrån verkliga däckhotell tillsammans med forskning och studier inom området, genomföra en rad olika analyser. Detta för att kunna besvara frågorna kvantitativt och/eller kvalitativt. Alla frågeställningar krävde dock flera antaganden för att vara möjliga att besvara. För att erhålla något att basera antagandena mot, genomfördes en fallstudie på verkliga däckhotell. Därefter skapades fem olika geometriska modeller baserade på de verkliga byggnaderna av volym, konstruktionsmaterial och ventilationsmöjligheter. Fallstudien visade även på stor variation på antalet däck som fanns placerade i däckhotell. Dock kan det konstateras att brandbelastningen i ett däckhotell överskrider 1600 MJ/m2 golvarea. Det konstruktionsmaterial byggnaden är uppförd med har stor inverkan på temperaturen i brandrummet. Däckhotell uppförda med en betongkonstruktion ger bättre förutsättningar för de brandavskiljande komponenterna att upprätthålla den brandbegränsande funktionen, detta i jämförelse med ett däckhotell uppfört av plåt med isoleringskärna. En brandcellsgräns som utsätts för den temperaturutveckling som sker i byggnad med väggar och tak av plåt-/isoleringskonstruktion, kommer eventuellt inte att begränsa brandspridningen under avsedd tid. De två skyddsbarriärerna som anges i BBR för att begränsa brandspridning mellan byggnader är skyddsavstånd eller att ytterväggen utformas som en brandcellsgräns, men där funktionen av en brandcellsgräns blir beroende av byggnadens konstruktionsmaterial. Fungerande skyddsavstånd är under förutsättning att öppningarna i fasad är begränsade och inte är större än en normal garageport. Syftet med att skydda närliggande byggnader uppfylls därmed inte. Skyddsavståndet bör vara i relation till arean på möjliga öppningar istället för ett fast värde. Ska skyddsavståndet vara fast bör det ske reglering av arean på möjliga öppningar och begränsa storleken eller kritisk strålningsnivå som får uppkomma på närliggande byggnad. Granskning av räddningsmanskapets säkerhet var en jämförelse mellan BBR och intervjuer på hur en räddningsinsats skulle kunna genomföras. Det som diskuterades var vilka risker branden och byggnaden utgör, samt hur dessa kan påverka genomförandet av insatsen. Brandtekniska åtgärder för att ta hänsyn till räddningsmanskapets säkerhet vid insats finns inte i erforderlig omfattning, vid brandteknisk projektering enligt förenklad dimensionering. Utan tidig detektion är risken överhängande att branden är för omfattande för att användning av invändiga brandposter för begränsning ska kunna vara möjlig. Dock är den enskilt viktigaste åtgärden för räddningsmanskapets säkerhet är att säkerställa tillgången till rätt mängd släckvatten vid byggnaden. Däckhotell placerade i containers är den enda byggnadsgeometri vilken kan projekteras enligt förenklad dimensionering. Den lagringsmetoden ger bäst möjlighet till en lyckad räddningsinsats och låg riskbild, och de är den enda modellen där brandcellsgränser helt klart skulle uppfylla sitt syfte både i klass EI 30 och EI 60. Containers har normalt inga fönster eller andra likvärdiga öppningar.
The aim of the thesis is mainly to investigate the risks that exist in case of fire in tire hotels and to evaluate whether society's requirements for fire protection in buildings are enough to manage this level of risk. Society's requirements in the study are Boverket's building regulations, BFS 2011:6 with amendments up to BFS 2020:4, (BBR) and the requirements that takes place in accordance with simplified design. The requirements in BBR have been quantified to enable a comparison between BBR and the actual conditions found in tire hotels. The study only treats three of the five items which BBR is based on. Development and spread of fire and smoke within the construction works is limited, spread of fire to adjacent construction works is limited and consideration has been taken to the rescue team's safety in case of fire. It exists some experience of fires in tire storage, but not a general picture of how a tire hotel should be design according to the building regulations, nor if it´s compatible with the building regulations' intention or the rescue team's practical experience of carrying out a rescue operation. The question is how the fire protection should be designed in tire hotels so that society's requirements can be fulfilled? When it can be thousands of tires which are stored at the same time in a tire hotel. The method to answer the questions was to carry out a few different analyses based on real tire hotels, together with research and studies in this area, so the questions could be answered quantitatively and/or qualitatively. However, all questions required some assumptions to be answered. To obtain something to base the assumptions against, a case study on real tire hotels was conducted. Five different geometric models were therefore created based on the buildings in terms of volume, construction materials and ventilation openings. The case study also showed a great variation in the number of tires that were stored in the hotels. Even with the variation, it can be stated that the fire load in a tire hotel exceeds 1600 MJ/m2 per floor area. The buildings construction material has a big impact on the fire temperature in the room. Tire hotels with a concrete construction provide better conditions for the fire-separation components to maintain the limiting function, in comparison with a construction of metal sheets with a core of insulation. A fire compartment boundary that is exposed to a temperature rise that occur in a metal structure, may not have the function over time it supposed to limit the spread of fire to other rooms during the intended time. BBR specifies two protective barriers to limit the spread of fire to adjacent construction, which are safety distances or that an exterior wall is designed as a fire compartment boundary. The function to limited fire spread by a fire compartment boundary is dependent on the building's construction material to fulfill its purpose. For a safety distance to work, the openings in the facade must be limited and not larger than a normal garage door. The purpose of protecting adjacent construction is therefore not fulfilled. The safety distance should be in relation to the area of openings instead of a fixed value. If the safety distance is a fixed value, the areas of openings should be regulated, if not, the size of the critical radiation that occur on an adjacent construction should be limited. Examination of the rescue team's safety was a comparison between BBR and interviews on how a rescue operation could be carried out. Under the interviews it was discussed what type of risks that are caused by the fire and the building, and how these risks can affect the implementation of the operation. The fire technical arrangements do not fulfill its purpose, to create the level of safety that are required for the rescue team when the fire technical design is according to a simplified design. Without early detection, the risk is imminent that the fire is too large for a person to use an indoor fire hydrant. The most important arrangements for the safety of the rescue team are however to ensure access to the right volume of water near the building. Tire hotels placed in containers are the only type of building which can be projected according to simplified design. This storage method provides the best opportunity for a successful rescue operation with a low risk. Containers are also the only geometric model where fire compartment boundary would clearly fulfill its purpose, in both class EI 30 and EI 60. Containers have normally no windows or other equivalent openings.

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Davies, Gwilym Matthew. "Fire behaviour and impact on heather moorland." Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/2609.

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For roughly the past 200 years land-managers have used the practice of “muirburning” to manipulate the structure of heather (Calluna vulgaris) to create a patchwork of habitat structures able to provide forage and nesting sites for red grouse (Lagopus lagopus scoticus) as well as grazing for sheep (Ovis aries) and red deer (Cervus elaphus). This thesis investigates both the behaviour and impact of management fires in recognition of the need to develop multi-aim land management practices that ensure both continued productivity and protection of biodiversity in the face of climatic and environmental change. Fuel structure and loading are crucial controlling factors on both fire behaviour and impact governing both rate of spread and heat release to the ground surface. A visual obstruction method is developed that estimates total and fine fuel loading as well as the structure of the heather canopy. In order to adequately understand fire impact a dimensional analysis approach is taken to estimating the mass of burnt heather stems. Experiments at a number of spatial and temporal scales relate variation in heather fuel moisture content to stand structure and variation in weather conditions. Monitoring shows moisture contents to be relatively stable temporally, but spatially variable. Periods of extreme low moisture contents in early spring are associated with frozen ground, winter cuticle damage and physiological drought. Such conditions may have contributed to the large number of wildfires in 2003. A replicated plot design was used to investigate the effect of weather conditions and fuel loading on fire behaviour. An empirical approach is taken to fire behaviour modelling with equations describing rate of spread and fireline intensity being developed on the basis of fuel structure descriptors and windspeed. The theoretical negative correlation between fuel bed density and rate of spread is demonstrated to hold true for heather stands, while the impact of heterogeneity in fuel bed structure is also investigated. Redundancy Analysis is used to investigate the influence of multiple predictors on a number of aspects of fire behaviour including: rate of spread, fireline intensity, flame length and ground surface heating. Data from this and previous studies are used to ground-truth a number of fire behaviour prediction systems including BehavePlus and the Canadian Fire Behaviour Prediction System. Finally linkages between fire behaviour, fire severity and heather regeneration are investigated. A number of proxy measures of ‘Immediate Severity’ are tested and used to examine the influence of fires on plant regeneration. The post-fire development of stands is shown to relate primarily to stand age and structure before burning, and to post-fire substrates rather than variation in fire behaviour and severity.

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Eriksson, Kajsa, and Löfgren Jenny. "Brandbelastning i träbyggnader : Jämförande beräkning och kartläggning om hur branschen hanterar permanet brandbelastning." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-49353.

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Wood is a renewable material, it is strong in relation to its weight, climate smart but also combustible. Owing to its many advantages and the easy access in Sweden, wood is motivated as a topical building material. However, the aspects related to the combustible nature need to be considered in the design of buildings with a wooden frame. Whether and in such cases how to take into account the increased permanent fire load is a problem of which there are shared opinions. Today's regulatory framework is unclear in some aspects in its formulation and thus leaves room for interpretation. The purpose of this work is to investigate the reasonableness of tabulated data for permanent fire load and the sharp boundary between a BR1 building and a BR0 building but also by surveying how the industry handles the issue. In order to assess the reasonableness for the tabulated data, the method has been calculations with two different methods; one that follows BBR's guidelines (method 1) and another where calculations of the charring depth (method 2) have been performed, as well as a survey and a literature study. The result from the calculations in method 1 shows that in order for the level of the total fire load not to exceed the standard value for a residence of 800 MJ/m2, a low coefficient is required, and thus in principle all wood is assumed to be protected. According to the calculations in method two, it is possible to read out how the permanent fire load is affected by different protective linings and carbonation rates. The survey shows that the most common way to dimension fire protection is through simplified sizing, which entails that one does not have to consider whether the permanent fire load increases due to a combustible frame. There are divided opinions about whether Boverket's rules are enough to achieve adequate protection and how to handle it. The literature study shows that for the timber frame to be counted as fully protected it needs to be three layers of fire gypsum board in the ceiling and that two layers on the walls. Several conclusions can be drawn; the calculations indicate that a permanent fire load of 200 MJ/m2 (2013:11) is unreasonable in a wooden frame building also that if the permanent fire load is considered it becomes costly both economically and in terms of space. Even that Boverket's rules need to be clarified and adapted further against tall wood buildings and that fire projectors work differently and the experience of working with tall wood buildings differs greatly.

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Ross, Timothy Ian. "Fuel load characterisation and quantification for the development of fuel models for Pinus patula in South Africa." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/20904.

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Thesis (MScBosb)--University of Stellenbosch, 2004.
ENGLISH ABSTRACT: The characteristics and total fuel load of the forest floor (FF) and harvest residue (HR) are needed to develop tools that can be used for fuel load management, fire risk analysis and fire behaviour prediction for P. patula grown in the summer rainfall area of South Africa (SA). Forest floor depth, mass and ash-free mass were measured and there was generally a greater range in depth under sawtimber (ST) stands than under pulpwood (PLP) stands. Forest floor loads, prior to ashing, ranged from 21 - 168 t ha-1 and 27 - 72 t ha-1, for ST and PLP stands, respectively and loads increased linearly with stand age. Sawtimber and PLP stands were analysed together, which resulted in a significant correlation between depth and mass (r2 = 0.78, n = 31). A loss on ignition procedure carried out on sub-samples of the FF improved the relationship between the FF depth and the ash-free mass for the different stands, and provided a more accurate model for the prediction of mass from depth. A multiple regression analysis revealed that age, altitude and mean annual precipitation (MAP) provided the best subset and accounted for 72% of the variation in the FF mass observed. The effect of increasing FF load and increasing moisture content on the fireline intensity (FLI) was examined using the fire behaviour prediction programme, BehavePlus. Harvest residue was quantified and characterised in terms of fuel size classes, under current silvicultural regimes for ST and PLP, for the development of fuel models for this species over its planted range in SA. An investigation into the proportion (by mass) of the 1- (0.0 - 0.6 cm), 10- (0.6 – 2.5 cm), 100- (2.5 – 7.6 cm) and 1000-hr (> 7.6 cm diameter) fuel classes of the total HR mass indicated that there was a significant difference between the mass of the 1-, 10- and 1000-hr fuel classes of the two silvicultural regimes, and no significant difference for the 100-hr fuel class. Two fuel models for P. patula HR and two models for standing timber were developed using the new model (NEWMDL) programme of BEHAVE and tested in BehavePlus. Nutrient concentrations were used with FF layer and HR size class load data to estimate the quantities of nutrients held in the fuel and to describe nutrient distributions in the fuel complex. Significant differences in the nutrient concentration of the FF layers and fuel components were observed which has important implications for fuel management. The concentration of N determined in this study, relative to that determined in other similar studies on P. patula was low. Forest floor loads were predicted and nutrient pools calculated for typical ST and PLP stands at both low and high altitude to provide insight into the nutrient distributions within the fuel complex.
AFRIKAANSE OPSOMMING: Die karaktereienskappe en totale brandstoflading van die bosvloer (FF) en kaalkap oorskot (HR) word benodig om instrumente te ontwikkel wat gebruik kan word vir brandstoflading bestuur, brandgevaar ontleding en brandgedrag voorspelling vir P. patula, wat in die somer reënvalgebied van Suid-Afrika groei. Die bosvloer diepte, massa en asvrye massa is gemeet en daar was oor die algemeen ‘n groter variasie in diepte onder saaghout (ST) opstande as onder pulphout (PLP) opstande. Die bosvloerladings, voor verassing, het varieer van 21 – 168 t ha-1 en 27 – 72 t ha-1 vir ST en PLP opstande respektiwelik. Ladings het linieêr vermeerder met opstand ouderdom. Saaghout en PLP opstande is saam geanaliseer en het tot ‘n betekenisvolle korrelasie gelei tussen diepte en massa (r2 = 0.78, n = 31). ‘n Verliestydens- ontbranding prosedure is uitgevoer op die FF monsters en het die verhouding tussen FF diepte en die asvrye massa van die verskillende opstande verbeter. Dit het ook gelei tot akkurater model vir die voorspelling van massa vanaf diepte. ‘n Veelvoudige regressie analise het aan die lig gebring dat ouderdom, hoogte en gemiddelde jaarlikse reënval (MAP) die beste sub-groep verskaf, en het 72% van die variasie in die FF massa verklaar. Ondersoek is ingestel op die effek van toenemende FF lading en toenemende voginhoud op die brandlyn intensiteit (FLI) deur die brandgedrag program, BehavePlus, toe te pas. Die kaalkap oorskot is gekwantifiseer en gekarakteriseer volgens brandstof grootteklasse, onder die huidige boskultuurstelsels vir ST en PLP, vir die ontwikkeling van brandstofmodelle vir hierdie spesie oor die betrokke groeistreek in SA. ‘n Ondersoek in die verhouding (volgens massa) van die 1- (0.0 – 0.6 cm), 10- (0.6 – 2.5 cm), 100- (2.5 – 7.6 cm) en 1000-uur (> 7.6 cm deursnee) brandstofklasse van die totale HR massa het aangedui dat daar ‘n betekenisvolle verskil is tussen die massas van die 1-, 10- en 1000-uur brandstofklasse van die twee boskultuurstelsels, en geen betekenisvolle verskil vir die 100- uur brandstofklas nie. Twee brandstofmodelle is ontwikkel vir P. patula HR en twee modelle vir staande hout deur gebruik te maak van die nuwe model (NEWMDL) program van BEHAVE en getoets in BehavePlus. Voedingstof konsentrasies is gebruik, tesame met die FF laag en HR klasgrootte ladingdata, om die voedingstof inhoud van die brandstof te skat en om die voedingstof verspreiding te beskryf in die brandstofkompleks. Betekenisvolle verskille is waargeneem in die voedingstof konsentrasies van die FF lae en brandstof komponente wat belangrike implikasies inhou vir brandstofbestuur. Die konsentrasie wat vir N in hierdie studie bepaal is, was laag relatief tot ander soortgelyke studies vir P. patula. Die bosvloer ladings is voorspel en voedingstofpoele bereken vir tipiese ST en PLP opstande vir beide lae en hoë hoogtes om insig te verkry, sodat insig verkry kon word in die voedingstof verspreidings binne die brandstofkompleks.

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Issa, Angelo, Maher Machhadi, and Mircea Barbu. "YTBEHANDLADE TRÄELEMENT : En studie av brandskydd, bärförmåga, pris och miljöpåverkan av ytbehandlade träelement." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-55197.

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The current Swedish building code (Boverkets Byggregler, BBR) is very strict regarding fire-safety in high-rise timber structures because of the heightened risk of fast flame spread or structural failure in case of fire. Fire safety solutions, that are used in timber structures must therefore be optimal to contain flames from spreading in the event of fire. The current building code requires that load-bearing elements must withhold their load-bearing capacity for 60 minutes under fire. The purpose of this study was to research the effect that different fire-retardant surface treatments, have on fire protection of a load bearing, laminated timber element. Thereafter, a short analysis was made on the environmental impact of the fire-retardant surface-treatments in question and finally, a cost analysis and comparison were conducted with regard to different fire-safety solutions such as fire-resistant gypsum board and a combination of fire-resistant gypsum board and stone-wool. The methods used in this study are a combination of theoretical reviews and theoretical calculations. A theoretical review was conducted in order to collect the information needed to understand the behavior of timber under fire, the impact of fire-resistant surface treatments on fire protection, and the environmental impact of the actual surface treatments. Therefore, a series of theoretical calculations were made in accordance with European standards (Eurocodes) in order to present the impact in numbers. The calculations made were concerning a laminated timber beam with the dimensions of 145 x 450 x 6000 [mm] and took into account the remaining cross-section of the timber element under various timestamps during fire with regard to fire-stage, charring-rate, and fire coating. The results of this study indicate that the moment-capacity and shear-capacity of an untreated beam decrease constantly under fire and does not fulfill the requirements of the Swedish building code. Thereafter, in case that the same timber beam is fire-treated with a fire-retardant surface treatment. The moment-capacity is observed to increase in the first stage of fire, were the fire-protection of the surface-retardant treatment is still in action. Therefore, after fire-protection ceases, the moment-capacity of the timber beam is calculated to decrease in different rates with regard to fire-stage. The shear capacity of the treated beam is calculated to decrease under fire with a time-displacement of 30 & 60 minutes in comparison to the untreated element. The conclusions are that the studied surface treated timber beam and the actual fire treatments fulfill the requirements of the Swedish building code. Have insignificant environmental impact and are in comparison to other solutions cheaper.

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Sido, Ivan, Martin Kassar, and Reem Bassi. "DIMENSIONERING AV TRÄTAKSTOLAR VID BRANDFALL : Enligt Kategori R30, R60." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-55492.

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The following project work studies trusses and roof structures and their performance during a fire in terms of rules and requirements that needs to be considered. Determination of how resistant truss or roof construction is still heavily dependent on the subjective experience and assessment of professional. It means that nowadays stages of this defining of fire resistance of roof/truss are still in need of clarification. The load combination for accidental load is compared to the ultimate limit state during the fire and it was showed that the loads were lower. The strength of timber during the fire was calculated by the two methods. Calculations by both methods revealed that timber used in construction can withstand fire by 0 minutes. However, fire resistance of the wooden materials can be improved by different techniques that were described in this study. The biggest improvement of fire resistance can be achieved with the help of covering - gypsum boards and rockwool, or even with wooden covering if lower protection is needed. As well, many fire-retardant treatments were developed that can improve wood performance during fire by slowing down the spread of fire, by limiting the building up of smoke and other volatiles. Instead of fire-retardant treatment fire retardant paints can be used too. This study showed stages of establishing fire requirements of wooden roof structures by two examples. In this study, two calculations were performed for two different house types, a family house, and an apartment building, to compare the difference between normal load dimensioning and fire load dimensioning. In the fire load dimensioning method, two different times were considered - R30 and R60 load capacity. When calculating the normal load dimensioning, it has been shown that an unprotected truss has no fire resistance, and that the truss has a fire resistance, with respect to bearing capacity, which corresponds to R0, which means that it must be protected for the required time.
Samhällsbyggnad
Husbyggnad
Konstruktion

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Hothan, Sascha, and Daniel Ehlig. "Hochtemperaturverhalten von Stahlbetonplatten mit Textilbetonverstärkung." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-78024.

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Die Verwendung von Endlosfilamenten aus Carbon als Bewehrungsmaterial für Beton, sogenannter Textilbeton, bietet die Möglichkeit der Sanierung und der Verstärkung bestehender Stahlbetonkonstruktionen. Dabei muss die Frage nach dem Feuerwiderstand von derart verstärkten Tragwerken beantwortet werden. Aufschluss darüber liefern Brandversuche. Mit Textilbeton verstärkte Stahlbetonplatten haben in Brandversuchen nach der Einheits- Temperaturzeitkurve bei 33 % der Traglast mehr als 60 Minuten standgehalten. Bei 50 % der Traglast kam es nach einer Branddauer von 55 Minuten, bei 65 % nach 30 Minuten, zu einem Zugversagen der textilen Verstärkungsschicht. Bei während des Brandes unbelasteten bzw. gering belasteten Platten lagen die im Anschluss ermittelten Resttragfähigkeiten bei 65 % der Bruchlast nach 30 Minuten Branddauer bzw. bei 50 % der Bruchlast nach 60 Minuten Branddauer. Während und nach der Beflammung waren zunehmende Durchbiegungen und Rissbreiten erkennbar. Es traten aber keine Abplatzungen auf, weshalb die Verstärkungsschicht aus Textilbeton als zusätzliche Betondeckung für die Stahlbewehrung angerechnet werden kann. Diese außerordentlich positiven Ergebnisse zeigen, dass für verstärkte Konstruktionen Feuerwiderstandsklassen von F60 bzw. R60 ohne zusätzliche Maßnahmen erreicht werden können. Dies ist von hoher Relevanz für die wirtschaftliche Anwendung dieser Verstärkungsmethode. Für ein umfassendes Verständnis der Interaktion zwischen den Bewehrungen Textil und Stahl sowie der Versagensmechanismen während des Brandes, sind weitere Erkenntnisse über die mechanischen Eigenschaften von Textilbeton im Hochtemperaturbereich nötig. Auch der Einfluss der Oxidation des Carbons konnte nicht abschließend beurteilt werden
Using endless carbon filaments for concrete reinforcement, so called textile reinforced concrete, the possibility of reconstruction and strengthening of existing concrete structures arises. The question concerning fire resistance of structures strengthened like this has to be answered. Fire tests provide answers. Steel reinforced concrete slabs strengthened with textile reinforced concrete loaded with 33 % of ultimate load survived an ISO-fire for 60 minutes. Loaded with 50 % and 65 % of ultimate load the slabs failed after 55 minutes and 30 minutes of fire exposure due to tension failure of the textile reinforcement layer. Slabs not loaded or with a low load level during fire exposure showed remaining bearing resistances of 65 % of ultimate load after 30 minutes and 50 % of ultimate load after 60 minutes of fire exposure. During and after fire exposure rising deflections and growing crack widths were observed. However no spalling occurred. Therefore the textile reinforced concrete layer can be taken into account as concrete covering for the steel reinforcement. Those extraordinary positive results document, that reinforced concrete structures with additional fibre reinforced concrete can achieve fire resistance classes of R60 without additional provisions. To achieve comprehensive understanding of interaction between steel and fibre reinforcement and failure mechanisms in case of fire more knowledge concerning the mechanic properties of fibre reinforced concrete at high temperatures is essential. The influence of oxidation of the carbon fibres could not fully be answered

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Jafarian, Mostafa. "Behaviour of reverse channel connection to concrete filled hollow tube columns under fire conditions." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/behaviour-of-reverse-channel-connection-to-concrete-filled-hollow-tube-columns-under-fire-conditions(f60a80b2-a053-49d7-bbaf-22de4291a8e3).html.

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This thesis presents the results of a research project to investigate the behaviour of the two components of a reverse channel connection to concrete filled tubular sections: the reverse channel and the steel tubular section, at both ambient and elevated temperatures. This research forms part of a European Union funded project on the robustness of joints to composite columns under fire conditions. The specific objectives of this research are to develop methods of quantifying the load-deformation behaviour at various temperatures of the two components. This research has been carried out through a combination of experiments, numerical simulations and analytical developments. Two series of tests have been carried out at different elevated temperatures, one for the reverse channels with lateral loads to the web applied as tensile loads through bolts and one for the concrete filled tubular sections under lateral loads applied through two steel plates (simulating the legs of a reverse channel) in the longitudinal direction of the section. These tests have been used to provide data for the validation of the numerical models based on using the general finite element package ABAQUS. The validated numerical models have been used to conduct a number of parametric studies to provide extensive data for the development of analytical methods to determine the load-deflection characteristics of the two components. For the reverse channel web, the load-deflection relationship consists of two parts and this research has developed analytical equations to predict initial stiffness, yield and ultimate resistance. The initial stiffness is based on extending and simplifying the Timoshenko solution for a plate under a block of lateral loads. The yield resistance is based on the yield line solution that the failure patterns were chosen based on the results attained from test and simulations. The ultimate resistance was calculated based on virtual work principle for the patterns considered in the yield resistance part. For the rectangular concrete filled tubular sections under lateral pulling forces applied through two plates, the load-deflection curve consists of two parts, depicting a linear phase followed by a nonlinear part. This research has developed expressions to calculate initial stiffness, yield resistance, and ultimate resistance. The initial stiffness is formulated according to the Timoshenko solution for a partially loaded plate. The yield resistance is determined by employing yield line solution for the yield patterns obtained from both the test and FE modelling. The ultimate resistance is evaluated by implementing the virtual work principle to the patterns considered in former part. The analytical load-deflection solutions have been compared with the numerical simulation and the experimental results and the agreement is generally satisfactory.

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Rodrigues, Cassy Anne dos Santos. "Quantas vezes devemos queimar o Cerrado? O efeito da frequência do fogo em comunidades vegetais de campo sujo de Cerrado /." Rio Claro, 2019. http://hdl.handle.net/11449/191448.

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Orientador: Alessandra Tomaselli Fidelis
Resumo: O Cerrado é formado por fisionomias campestres e savânicas, evoluiu na presença do fogo e depende dele para manter suas fisionomias e biodiversidade. O regime de fogo influencia diretamente na montagem da comunidade vegetal, na regeneração e nas habilidades competitivas das plantas. A frequência é um dos fatores do regime de fogo e alterações nela podem ser prejudiciais até mesmo para plantas e comunidades adaptadas ao fogo. Portanto, este estudo busca compreender os efeitos de diferentes frequências de fogo em comunidades de campo sujo de Cerrado. Para isso, foram realizados levantamentos da vegetação e coleta de biomassa em áreas com diferentes históricos de fogo (excluído do fogo, queimadas anualmente e bienalmente), o que forneceu os dados de composição e produtividade da comunidade. Os levantamentos, incluindo a cobertura (%) por espécie, foram realizados em 10 subparcelas de 1x1m por tratamento (10 subparcelas/tratamento,3 tratamentos, 4 parcelas/tratamento). Avaliamos também através da taxa de propagação (m.s-1), eficiência de queima (%) e intensidade (kW.m-1) entre outros parâmetros do fogo, os efeitos de diferentes frequências no comportamento do fogo. Nossos resultados mostraram que a riqueza de espécies das comunidades vegetais foi maior nas áreas com frequência anual de fogo do que nas excluídas, 6 meses após o fogo e maior para as bienais do que as excluídas 12 meses após o fogo. O índice de diversidade foi maior no tratamento anual de queima antes e 12 meses apó... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The Cerrado is formed by grasslands and savannah physiognomies, evolved in the presence of fire and depends on it to maintain its physiognomies and biodiversity. The fire regime influences the plant community assembly, the regeneration and the competitive abilities of the plants. Frequency is one of the factors of the fire regime and changes in it can be detrimental even to fire-adapted plants and communities. Therefore, this study aimed to understand the effects of different fire frequencies in campo sujo of Cerrado communities. For this, vegetation surveys and biomass collection were carried out in areas with different fire histories (excluded from fire, burned annually and biennially), which provided community composition and productivity data. Surveys, including coverage (%) by species, were performed on 10 1x1m subplots per treatment (10 subplots / treatment, 3 treatments, 4 plots / treatment). We also evaluated through propagation rate (m.s-1), firing efficiency (%) and intensity (kW.m-1) among other fire parameters, the effects of different frequencies on fire behavior. Our results showed that species richness of plant communities was higher in areas with annual fire frequency than in excluded areas 6 months after fire and higher for biennials than those excluded 12 months after fire. The diversity index was higher in the annual burn treatment before and 12 months after the burns. Regarding the number of species per functional group, only the forbs presented increase a... (Complete abstract click electronic access below)
Mestre

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Santesson, Li. "Betongpelare och brand : En utvärdering av 500 °C isotermmetoden." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-25428.

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At the beginning of 2011, Sweden started using the European rules for structural design, the Eurocodes, instead of the previous national rules. In both the previous rules and the Eurocodes, it is possible to dimension concrete columns using tabled values. However, the required cross section measurements have increased considerably. Moreover, it is possible to dimension concrete columns using calculations, however, this is unusual. The development of a fire in a fire cell can be divided into the growth stage, the fully developed fire and the cooling phase. The duration of each phase, as well as the temperature, is dependent on a number of factors, e.g. the fire load, the size of openings and the geometry of the fire cell. In the Eurocodes there are standardized temperature-time curves that can be used in the dimensioning of a structural design, one of which is the standard temperature-time curve. The tabled values are based on this time-heat regime. When exposed to fire the strength of both concrete and reinforcements decreases. Regarding the reinforcement steel, the decrease is well documented. Concrete, however, is not a homogeneous material which makes the strength at elevated temperatures complex to determine. The dimensioning of concrete columns can be executed using tabled values. However, the objective of this report is a method called the 500 °C isotherm method. Using this method, concrete at temperatures above 500 °C is assumed not to contribute to the load bearing capacity. The residual cross-section retains its initial value of strength and modulus of elasticity. This results in a reduced cross-section. Subsequently, a reduced load bearing capacity is determined for the reinforcement steel due to the temperature. Thereafter, conventional calculation methods are used. The process of describing how the isotherm method should be implicated has been obstructed by the lack of explicit information in the Eurocodes. Furthermore, few people have knowledge about how the method should be used in practice. This has resulted in some assumptions based on logical arguments. A concrete column was evaluated for 60 and 90 minutes standard fire exposure to enable a comparison with the tabled values. The result showed that concrete columns can meet the requirements with a considerably smaller cross section. The calculated cross section measurements resulted in a value between the tabled values in the Eurocodes and those in the previous rules. Although the 500 °C isotherm method is the most simple of the simplified calculation methods, and the model in this report is limited to a circular, centrically loaded column, the method is complicated and time-consuming. It is therefore likely that it only will be used in special cases when the tabled values are inapplicable.
Vid årsskiftet 2010-2011 övergick Sverige från nationell standard till de europeiska standarderna för konstruktion, Eurokoderna. I den europeiska standarden, precis som i den gamla, kan betongpelare förenklat branddimensioneras med hjälp av tabellvärden. Kraven på minsta tvärsnitt har dock blivit avsevärt större. Detta har varit blivit svårt att förena med önskemål från arkitekter. Det är även möjligt att branddimensionera betongpelare med beräkningar. Detta är dock ovanligt. Brandförloppet i en brandcell kan förenklat delas in i uppvärmning, fullt utvecklad brand och avsvalning. Tiden för de olika faserna, liksom temperaturen, påverkas av en mängd faktorer. Några av dessa är mängden brännbart material, hur stora öppningar som finns och brandcellens geometri. I Eurokoderna finns standardiserade brandförlopp som kan användas vid dimensionering. En av dessa kallas standardbrandkurvan. Tabellvärdena är baserade på standardbrandpåverkan. Vid branddimensionering används en annan lastkombination än vid normaltemperaturdimensionering. Denna lastkombination ger en lägre last än vid brottgränsdimensionering. Både betong och armeringsstål förlorar bärförmåga vid förhöjda temperaturer. För armeringsstål är denna reducering väl dokumenterad. För betong, som inte är ett homogent material, är hållfastheten svårare att beräkna. Betongpelare kan dimensioneras enligt tre metoder: Vedertagna och beprövade detaljlösningar (Tabellerade värden) Förenklade beräkningsmetoder Avancerade beräkningsmetoder Fokus i denna rapport ligger på en av de förenklade beräkningsmetoderna, 500 °C isotermmetoden. Den utgår från att betong som har en temperatur över 500 °C försummas, emedan betong med en temperatur under 500 °C antas ha sin fulla bärförmåga. Därefter beräknas en reducerad hållfasthet för armeringsstängerna utifrån den temperatur de uppnår. Dimensionering sker sedan enligt traditionella metoder. Arbetet med att beskriva hur isotermmetoden ska användas har försvårats av bristande information i Eurokoderna. Dessutom finns det få personer som känner till hur metoden ska användas i praktiken. Detta har resulterat i vissa antaganden som underbyggts av logiska resonemang. För att kunna jämföra isotermmetoden med tabellerade värden kontrollerades en pelare för 60 och 90 minuters standardbrandpåverkan (se Bilaga A). Resultatet visade att pelare kan klara kraven med mindre tvärsnitt än i tabellen. Vid dimensioneringen erhölls ett tvärsnitt som låg mellan de nya och de gamla kraven. 500 °C isotermmetoden är den enklaste av de förenklade beräkningsmetoderna för betongpelare. Detta innebär dock inte att den är enkel. Trots att modellen i denna rapport har avgränsats till centriskt belastade, cirkulära pelare är metoden tidskrävande. Troligt är därför att den bara kommer att användas vid speciella fall då tabellmetoden inte är tillämpbar.

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Kaczyński, Marek. "Vliv změny požárně technických charakteristik na požárně bezpečnostní řešení stavby gymnázia." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226392.

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This thesis examines how the changes of fire technical characteristics could affect the fire safety solution of gymnasium. The fire safety solution was developed for this object. The idea is to prove, that this object, which was designed in 1995, meets current requirements for fire safety of buildings. The method and principles of this solution are described in the introductory part of this thesis. For unsuitable solution was designed modification of this solution, which meets the requirements of fire safety solution of gymnasium. This modification is focused on designing new escape routes. In the next part of thesis is designed object with different operational use - hotel. Subsequently are shown differences in assessment of fire safety solution of building gymnasium and hotel. In the end of this thesis is explained why the fire solution of gymnasium was unsatisfactory, and what are the main differences in assessment of objects with different operational use.

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Bizerra, Rafael Cavalcanti. "Modelo para otimização ao atendimento a ocorrências de incêndios: estudo de caso para a cidade de São Carlos - SP." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/18/18143/tde-10092014-151902/.

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O crescimento da população urbana requer o aumento dos serviços prestados pelos gestores públicos em consonância com as interações espaciais vividas pelo homem, tornando a administração do espaço urbano uma tarefa árdua e complexa. A inexistência ou a falha na prestação de serviços básicos relacionados com a segurança pública aumenta potencialmente os riscos de sinistros para a população. O objetivo desse trabalho é avaliar a distribuição espacial dos agentes e neutralizantes de incêndio na cidade de São Carlos-SP. Para essa finalidade estudou-se o posicionamento dos agentes e neutralizantes e suas relações no espaço, através de análises realizadas com o uso de um SIG, as quais indicaram a existência de problemas relacionados com a quantidade e a distribuição dos neutralizantes nessa cidade. Utilizando as ferramentas disponíveis no QGIS, foi possível desenvolver e propor uma solução estrutural para melhorar a alocação dos equipamentos de segurança e propor uma solução não estrutural por meio de tecnologia embarcada que proporcionou um menor tempo de deslocamento para abastecer as viaturas em casos de ocorrências de incêndios. Os cenários avaliados mostraram que é possível obter níveis de cobertura de toda a malha urbana, apenas com a realocação de parte dos equipamentos já instalados e com a instalação de alguns poucos hidrantes na rede.
The urban population growth requires increased services provided by public managers in harmony with the spatial interactions experienced by man, making the management of urban space an arduous and complex task. The absence or failure in providing basic services related to public security increases a lot the risk of accidents for the population. The aim of this study is to evaluate the spatial distribution of fire agents and neutralizers fire in the city of São Carlos-SP. For this purpose it was studied the positioning of the fire agents and neutralizers and their relations in space through analyzes with the use of a GIS, that indicated the existence of problems related to the amount and distribution of neutralizers in this city. Applying the tools available in QGIS, was possible to develop and propose a structural solution to improve the allocation of security devices and propose a non-structural solution using embedded technology that allowed shorter shift to water supply the vehicles in cases of occurrences of fires. The evaluated cases showed that it is possible to obtain coverage levels across the urban area, only reallocating the already installed equipment and the installation of a few more hydrants in the network.

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22

Rezai, Zahra. "Förutsättningar för byte av skivmaterial i regelstomsystem - brandsäkerhetsperspektiv." Thesis, Linnéuniversitetet, Institutionen för byggteknik (BY), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-98588.

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Bostadsbristen ökar i samhället och många byggföretag vill hitta en lösning som gör att det går att tillverka snabbare, billigare och säkrare byggnader. Att bygga moduler med trästomme är en lösning men användning av trä kräver särskilda kunskaper när det gäller brandskydd. Att skydda trästomme med gipsskivor kan vara en metod för att öka brandsäkerheten. Syftet med studien är att undersöka om Vida Building AB kan byta ut den bärande väggkonstruktionen i deras volymelement där reglarna skyddas av två gipsskivor av typ A med tjockleken 12,5 och en plywoodskiva med tjockleken 12,5 mm, mot en skiva av märket Fermacell, en så kallad fibergipsskiva. Bärförmågan har beräknats efter 60 minuters brand i väggkonstruktionen när gips-och plywoodskivor bytts mot skivor av Fermacell. Bestämning av bärförmågan hos konstruktionen gjordes med hjälp av två beräkningsmodeller. Resultatet visar att det går att använda en Fermacell skiva på 18 mm om reglarnas dimensioner ökas från 45x95 mm till 45x120 mm eller till 45x145 mm. Alternativt kan en bärförmåga motsvarande den för nuvarande konstruktion erhållas om två skivor av Fermacell med tjockleken 12,5 mm används.

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23

Studhalter, Jakob. "A probabilistic comparison of times to flashover in a compartment with wooden and non-combustible linings considering variable fuel loads." Thesis, University of Canterbury. Department of Civil and Natural Resources Engineering, 2012. http://hdl.handle.net/10092/7650.

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Prescriptive fire safety codes regulate the use of combustible room linings to reduce fire risk. These regulations are based on classification systems which designate materials according to their relative hazard when exposed to a standard fire scenario. However, no quantitative data sets on the fire risk of wooden lining materials exist which take into account relevant uncertainties, such as movable fuel loads in compartments. This work is a comparative risk analysis on the influence of wooden linings on the time to flashover in a compartment, considering uncertainties in the fuel load configuration. A risk model is set up for this purpose using B-RISK, a probabilistic fire design and research tool currently under development at BRANZ (Building Research Association of New Zealand) and the University of Canterbury. The risk model calculates fire spread in a compartment between fuel load items and from fuel load items to combustible linings. Multiple iterations are performed considering varying fuel load arrangements and input values sampled from distributions (Monte-Carlo simulation). The functionality and applicability of the risk model is demonstrated, comparing the model with experiments from the literature. The model assumptions are described in detail. Some of the model inputs are defined as distributions in order to account for uncertainty. Parametric studies are conducted in order to analyse the sensitivity of the results to input parameters which cannot be described as distributions. Probabilistic times to flashover are presented and discussed for an ISO 9705 compartment considering varying movable fuel loads and different lining configurations. The fuel load is typical for a hotel room occupancy. Effects of suppression measures are not considered. It is shown that flashover occurs approximately 60 seconds earlier if walls and ceiling are lined with wooden materials than if all linings are non-combustible. This value refers to the 5th percentiles of the time to flashover, i.e. in 5% of the cases flashover has occurred and in 95% of the cases flashover has not (yet) occurred. Referring to 50th percentiles (median values), the difference is approximately 180 seconds. Furthermore it is shown that with wooden wall and ceiling linings in approximately 95% of the iterations flashover occurs, whereas with non-combustible linings 86% of the iterations lead to flashover. After 900 seconds, in 90% of the iterations flashover occurs if walls and ceiling are lined with wooden materials, and in 77% of the iterations if the linings are non-combustible. Using different wooden lining materials (non-fire retardant plywood, fire retardant plywood, and MDF) has no significant effect on the probabilistic times to flashover. Varying the fuel load energy density has an influence only when all linings are non-combustible and when the fuel load energy density is relatively low (100–200 MJ/m2). This work contains recommendations regarding the further development of B-RISK, the research into the fire risk connected with wooden room linings, and suggestions regarding the further development of prescriptive fire safety codes.

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Ehlig, Daniel, Frank Jesse, and Manfred Curbach. "Stahlbetonplatten verstärkt mit Textilbeton unter Brandbelastung." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1244050720109-69672.

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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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25

Ranawaka, Thanuja. "Distortional buckling behaviour of cold-formed steel compression members at elevated temperatures." Queensland University of Technology, 2006. http://eprints.qut.edu.au/16417/.

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In recent times, light gauge cold-formed steel sections have been used extensively in residential, industrial and commercial buildings as primary load bearing structural components. This is because cold-formed steel sections have a very high strength to weight ratio compared with thicker hot-rolled steel sections, and their manufacturing process is simple and cost-effective. However, these members are susceptible to various buckling modes including local and distortional buckling and their ultimate strength behaviour is governed by these buckling modes. Fire safety design of building structures has received greater attention in recent times due to continuing loss of properties and lives during fires. Hence, there is a need to fully evaluate the performance of light gauge cold-formed steel structures under fire conditions. Past fire research has focused heavily on heavier, hot-rolled steel members. The buckling behaviour of light gauge cold-formed steel members under fire conditions is not well understood. The buckling effects associated with thin steels are significant and have to be taken into account in fire safety design. Therefore, a research project based on extensive experimental and numerical studies was undertaken at the Queensland University of Technology to investigate the distortional buckling behaviour of light gauge cold-formed steel compression members under simulated fire conditions. As the first phase of this research program more than 115 tensile coupon tests of light gauge cold-formed steels including two steel grades and five thicknesses were conducted at elevated temperatures. Accurate mechanical properties including the yield strength, elasticity modulus and stress-strain curves were all determined at elevated temperatures since the deterioration of the mechanical properties is one of the major parameters in the structural design under fire conditions. An appropriate stress-strain model was also developed by considering the inelastic characteristics. The results obtained from the tensile coupon tests were then used to predict the ultimate strength of cold-formed steel compression members. In the second phase of this research more than 170 laboratory experiments were undertaken to investigate the distortional buckling behaviour of light gauge coldformed steel compression members at ambient and elevated temperatures. Two types of cross sections were selected with various thicknesses (nominal thicknesses are 0.6, 0.8, and 0.95 mm) and both low and high strength steels (G250 and G550 steels with minimum yield strengths of 250 and 550 MPa). The experiments were conducted at six different temperatures in the range of 20 to 800°C. A finite element model of the tested compression members was then developed and validated with the help of experimental results. The degradation of mechanical properties with increasing temperatures was included in finite element analyses. An extensive series of parametric analyses was undertaken using the validated finite element model to investigate the effect of all the influential parameters such as section geometry, steel thickness and grade, mechanical properties and temperature. The resulting large data base of ultimate loads of compression members subject to distortional buckling was then used to review the adequacy of the current design rules at ambient temperature. The current design rules were reasonably accurate in general, but in order to improve the accuracy further, this research has developed new design equations to determine the ultimate loads of compression members at ambient temperature. The developed equation was then simply modified by including the relevant mechanical properties at elevated temperatures. It was found that this simple modification based on reduced mechanical properties gave reasonable results, but not at higher temperatures. Therefore, they were further modified to obtain a more accurate design equation at elevated temperatures. The accuracy of new design rules was then verified by comparing their predictions with the results obtained from the parametric study. This thesis presents a description of the experimental and numerical studies undertaken in this research and the results including comparison with simply modified current design rules. It describes the laboratory experiments at ambient and elevated temperatures. It also describes the finite element models of cold-formed steel compression members developed in this research that included the appropriate mechanical properties, initial geometric imperfections and residual stresses. Finally, it presents the details of the new design equations proposed for the light gauge coldformed steel compression members subjected to distortional buckling effects at elevated temperatures.

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Pool, Christiaan Frederik. "The effect of modified fuel loads on fire behaviour in Pinus patula and Eucalyptus macarthurii stands in the Mpumalanga Highveld forestry region of South Africa." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1010958.

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The effectiveness of harvesting slash treatments are questionable when wild fires, fuelled by post harvesting slash, burn out of control. In order to quantify effectiveness of various slash treatments, fire behaviour in Pinus patula and Eucalyptus macarthurii compartments in the Highveld area (Piet Retief) of Mpumalanga, South Africa, were assessed after application of five different post-harvesting slash treatments. Treatments included mulching, chopper rolling, windrowing, removal of slash (inter-windrowing) and broadcasting. Independent fuel and environmental variables were measured prior and during application of fire to the study areas and effects on fire behaviour were compared afterwards. Dependant fire behaviour variables such as the rate of spread, fire temperature and flame height were measured in respective slash treatment plots and compared. Results of the study indicated that fire behaviour assessed in mulched areas in both the P. patula and E. macarthurii compartments were significantly less intense when compared to fire behaviour in chopper roll, broadcast and windrow treatments. Fire behaviour in mulched plots compared favourably with areas where harvesting slash was removed (inter-windrow treatment). Comparisons between fuel loads of different treatments also indicated accelerated mineralization of organic material in mulched areas. Mulching of harvesting slash seems to be an effective method to restrict fire behaviour in post-harvesting compartments and should be considered as part of a fire management strategy.

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Heva, Yasintha Bandula. "Behaviour and design of cold-formed steel compression members at elevated termperatures." Queensland University of Technology, 2009. http://eprints.qut.edu.au/29310/.

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Cold-formed steel members have been widely used in residential, industrial and commercial buildings as primary load bearing structural elements and non-load bearing structural elements (partitions) due to their advantages such as higher strength to weight ratio over the other structural materials such as hot-rolled steel, timber and concrete. Cold-formed steel members are often made from thin steel sheets and hence they are more susceptible to various buckling modes. Generally short columns are susceptible to local or distortional buckling while long columns to flexural or flexural-torsional buckling. Fire safety design of building structures is an essential requirement as fire events can cause loss of property and lives. Therefore it is essential to understand the fire performance of light gauge cold-formed steel structures under fire conditions. The buckling behaviour of cold-formed steel compression members under fire conditions is not well investigated yet and hence there is a lack of knowledge on the fire performance of cold-formed steel compression members. Current cold-formed steel design standards do not provide adequate design guidelines for the fire design of cold-formed steel compression members. Therefore a research project based on extensive experimental and numerical studies was undertaken at the Queensland University of Technology to investigate the buckling behaviour of light gauge cold-formed steel compression members under simulated fire conditions. As the first phase of this research, a detailed review was undertaken on the mechanical properties of light gauge cold-formed steels at elevated temperatures and the most reliable predictive models for mechanical properties and stress-strain models based on detailed experimental investigations were identified. Their accuracy was verified experimentally by carrying out a series of tensile coupon tests at ambient and elevated temperatures. As the second phase of this research, local buckling behaviour was investigated based on the experimental and numerical investigations at ambient and elevated temperatures. First a series of 91 local buckling tests was carried out at ambient and elevated temperatures on lipped and unlipped channels made of G250-0.95, G550-0.95, G250-1.95 and G450-1.90 cold-formed steels. Suitable finite element models were then developed to simulate the experimental conditions. These models were converted to ideal finite element models to undertake detailed parametric study. Finally all the ultimate load capacity results for local buckling were compared with the available design methods based on AS/NZS 4600, BS 5950 Part 5, Eurocode 3 Part 1.2 and the direct strength method (DSM), and suitable recommendations were made for the fire design of cold-formed steel compression members subject to local buckling. As the third phase of this research, flexural-torsional buckling behaviour was investigated experimentally and numerically. Two series of 39 flexural-torsional buckling tests were undertaken at ambient and elevated temperatures. The first series consisted 2800 mm long columns of G550-0.95, G250-1.95 and G450-1.90 cold-formed steel lipped channel columns while the second series contained 1800 mm long lipped channel columns of the same steel thickness and strength grades. All the experimental tests were simulated using a suitable finite element model, and the same model was used in a detailed parametric study following validation. Based on the comparison of results from the experimental and parametric studies with the available design methods, suitable design recommendations were made. This thesis presents a detailed description of the experimental and numerical studies undertaken on the mechanical properties and the local and flexural-torsional bucking behaviour of cold-formed steel compression member at ambient and elevated temperatures. It also describes the currently available ambient temperature design methods and their accuracy when used for fire design with appropriately reduced mechanical properties at elevated temperatures. Available fire design methods are also included and their accuracy in predicting the ultimate load capacity at elevated temperatures was investigated. This research has shown that the current ambient temperature design methods are capable of predicting the local and flexural-torsional buckling capacities of cold-formed steel compression members at elevated temperatures with the use of reduced mechanical properties. However, the elevated temperature design method in Eurocode 3 Part 1.2 is overly conservative and hence unsuitable, particularly in the case of flexural-torsional buckling at elevated temperatures.

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Malmros, Catrine, and Johnson Andrea. "Brandpåverkan på skyddskonstruktioner i funktionsskyddsrum : En undersökning av resthållfasthet i betongbalkar." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-40032.

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In the beginning of the 21st century decisions were made regarding the decommission of the total defence in Sweden. Since then the security policy situation has changed, regarding both the risk of war and other types of treats such as terrorism. Due to this the total defence is now being re-established. The Swedish Fortifications Agency and Research Institutes of Sweden (RISE) has initiated the Centre of excellence for fortification (CFORT) to support the development of competence in fortification. In case of a crisis or war secured function shelters constitutes a significant part of the Swedish total defence by protecting important technology and activity.The purpose of this bachelor thesis is to investigate the remaining load bearing capacity in concrete constructions in secured function shelters after exposure to fire. This will provide a foundation for further research within the area of the effects of fire in secured function shelters. To achive this, experiments were conducted on nine concrete beams which were casted according to calculations based on the structural codes of the Swedish Fortifications Agency (FKR). Since fully scaled beams are difficult to manage and would not fit in the equipment being used, the beams were casted in a smaller size; 2000 x 150 x 210 mm. Samples of the concrete and the reinforcement were sent to the Swedish Cement and Concrete Research Institute (CBI) for tests which provided actual values of the compressive strength, yield point and modulus of elasticity. Six of the beams were in pairs exposed to fire in a specially built oven according to three different temperature curves. All the beams were later subjected to load until failure. Calculations regarding load bearing capacity were executed with both theoretical and actual values obtained from CBI. The results were compared to the results from the loading tests. During the last fire experiment the beams spalled, most likely due to the quickly rising temperature. The loading test showed that the strength of the beams which had not spalled were not significantly lower than the unaffected beams. Those beams showed a reduction of only 0 – 6 %. However, the beams which had spalled showed a reduce in strength of approximately 20 %.
Centrum för fortifikatorisk kompentens

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29

Erm, Lincoln P. Ferrarotto Phil. "Development of a five-component strain-gauge balance for the DSTO water tunnel." Fishermans Bend, Vic. : Defence Science and Technology Organisation Air Vehicles Division, 2009. http://hdl.handle.net/1947/10033.

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Mode of access: Internet via World Wide Web. Available at http://hdl.handle.net/1947/10033.
"November 2009". Available on the DSTO website as at DSTO at :http://dspace.dsto.defence.gov.au/dspace/bitstream/1947/10033/1/DSTO-GD-0597%20PR.pdf

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Antunes, Marco Antônio das Graças. "A gestão de riscos como alternativa de prevenção de incêndio em arquivos públicos : estudo de caso." Programa de Pós-Graduação em Engenharia Geotécnica. Núcleo de Geotecnia, Escola de Minas, Universidade Federal de Ouro Preto, 2011. http://www.repositorio.ufop.br/handle/123456789/2352.

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Submitted by Maurílio Figueiredo (maurilioafigueiredo@yahoo.com.br) on 2013-02-22T19:51:45Z No. of bitstreams: 1 DISSERTAÇÃO_GestãoRiscoAlternativa.pdf: 41214411 bytes, checksum: 7caa77944d2a0c8f76333d07df2ca056 (MD5)
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Made available in DSpace on 2013-02-25T14:13:29Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO_GestãoRiscoAlternativa.pdf: 41214411 bytes, checksum: 7caa77944d2a0c8f76333d07df2ca056 (MD5) Previous issue date: 2011
ABSTRACT: The buildings of public archives shelter documents of permanent value, which are of inalienable and imprescriptible guard. To check the level of fire protection to these permanent records in each building surveyed, it was applied the global analysis of fire risk using the Gretener Method. The text of the “IT 35-CBMMG”, based on this method of performance (widely known) provides fire protection alternatives for the historical buildings (and their contents) of Minas Gerais State, Brazil, when it is not possible or aesthetically desirable, the adoption of security normative or prescriptive measures. The research result showed that showed that the buildings where are installed the public archives are of no conformity to risk of fire due to an in the safety versus protection. Another quick observation was the high volume of documents on paper (main fire load) accommodated in rooms of insufficient area to contain them, incurring specific fire loads much higher than the stipulated level in the specific standard. With the successive employment of active and passive protection measures in these constructions, the safety factors after each trial immediately improved, giving the building and its occupants a pro-safety situation, compared to the outbreak of fire, until unfavorable.
As edificações sede de arquivos públicos custodiam documentos de valor permanente, sendo estes inalienáveis e de guarda imprescritível. Para verificação do nível de proteção contra incêndio a esses documentos permanentes, em cada uma das edificações pesquisadas, foi aplicada a análise global de risco de incêndio, decorrente do Método de Gretener. O texto da IT 35 do CBMMG, baseado nesse método de desempenho (mundialmente conhecido) fornece alternativas de proteção contra incêndio às edificações (e ao seu conteúdo) que compõem o patrimônio histórico mineiro, quando não seja possível ou esteticamente conveniente, a adoção de medidas de segurança de ordem normativa ou prescritiva. O resultado da pesquisa mostrou que as edificações onde estão instalados os arquivos públicos estão em situação de insegurança frente ao risco de incêndio, em razão de um desequilíbrio na relação segurança versus proteção. Outra rápida constatação foi o elevado volume de documentos no suporte papel (principal carga de incêndio) acomodados em espaço de superfície insuficiente para comportá-los, incorrendo cargas de incêndio específicas muito superiores ao valor estipulado em norma. Com o emprego sucessivo de medidas de proteção passiva e ativa nessas edificações, os coeficientes de segurança melhoraram imediatamente a cada ensaio, conferindo ao prédio e aos seus ocupantes uma situação pró-segurança, frente ao risco de incêndio, até então desfavorável. Edificações que abrigam instituições arquivísticas, necessitam de um de sistema de segurança contra incêndio e pânico que monitore diuturnamente as áreas de interesse, com rápida detecção de um foco de fogo e acionamento de alarme, seguido de imediato e eficiente combate por brigadistas treinados, no mínimo. ______________________________________________________________________________________________________

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31

Öberg, Andreas, and Fredrik Lejdström. "Brandskydd i byggnader med exponerad stomme av KL-trä : En kartläggning av olika brandtekniska lösningar för flerbostadshus." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-55205.

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Purpose: The purpose with this work has been to investigate and map selected fireprotection methods in a number of projects. The possibilities and limitations with exposedCLT have been investigated. Method: The method consists of a literature study, interviewstudy, construction site visit and survey. The literature study has been carried out with theaim of presenting relevant facts to the subject and creating a basis for the interview study.The interviews were conducted with fire consultants for the work´s investigated projects.Two of the projects also included construction site visit, of which one of the projects belongsto the partner of this work, Peab. During the visits of the construction sites a tour of thebuilding were carried out and shown where the exposed CLT was placed. The results from theinterviews and construction sites visits are the basis for the survey. Results: The resultsshow that analytical dimension of the fire protection is required when constructing multistory residence with internally exposed CLT. Limitations with exposed CLT are due, amongother things, to the fact that untreated wood does not fulfils the requirements set in BBR forthe surface layer. Delamination contributes to increased fire load as the underlaying slats areexposed to fire. The current study contains two projects carried out with exposed CLT,Notuddsparken and ETC apartment buildings. The projects have dimensioned each withanalytical dimension but with different fire protection methods. Notuddsparken has beenconstructed with automatic sprinkler systems and the ETC apartment buildings have beenconstructed with fire protection impregnation of the exposed CLT. Conclusions:Conclusions established in the work shows that when using exposed CLT analyticaldimension of the fire protection is required. Most of the fire consultants in this work haveexpressed that they do not feel comfortable with dimensioning fire protection for buildingswith exposed CLT, based on the current state of knowledge.

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Kelly, Gordon. "Load Introduction in Carbon Fibre Composites for Automotive Applications." Licentiate thesis, KTH, Aeronautical Engineering, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1455.

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Sanderson, Brian T. "Reducing Seed Load in the BitTorrent File Sharing System." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2439.pdf.

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Yii, H. W. (Jennifer). "Effect of Surface Area and Thickness on Fire Loads." University of Canterbury. Civil Engineering, 2000. http://hdl.handle.net/10092/8304.

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The report reviews the effect of surface area and thickness of fire loads in predicting the value of the heat release rate. The investigation arises from current Ph. D research at the University of Canterbury identifying the need for fire load data, which also includes the exposed surface area of the fuel items, so that the rate and duration of burning can be better assessed, especially during post-flashover fires. This is because at some stage of the fire, the fuel is no longer dependent on the ventilation characteristics but the surface area exposed to the fire. The investigation of the effect of surface and thickness on fire load is first carried out with the burning of single items, such as furniture normally found in each building occupancy. Later, fire load surveys on a range of typical building occupancies, such as university offices, motels and residential are conducted. Simple models for calculating the surface area of the fire load, especially for wood and plastic materials have been determined. Based on the methodology developed for the investigation, it is found that the larger the exposure of the fuel surface area to the fire, the higher the heat release rate, and the thicker the fuel, the longer the duration of burning. In other words, the value of the heat release rate is a function of the surface area, while the duration of burning is a function of the thickness of the fuel. Burning behaviour of the fire load inside a fire compartment during a post-flashover fire, based on the exposed surface to the fire is also presumed. Previous fire load surveys conducted are also included for comparisons of the results. Recommendations for future study of the effect of the surface area and thickness on fire loads during a fire are provided.

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Piloto, P. A. G. "Análise experimental e numérica do comportamento de estruturas metálicas sujeitas à acção do fogo." Doctoral thesis, Universidade do Porto, Faculdade de Engenharia, 2001. http://hdl.handle.net/10198/2093.

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Neste trabalho é apresentado um estudo sobre o efeito da acção do fogo em estruturas metálicas, tendo sido elaborado um estudo numérico e experimental de um fenómeno de instabilidade estrutural relativo à encurvadura lateral torsional de vigas a elevadas temperaturas. Foram efectuados ensaios destrutivos em vários perfis com vista à determinação da carga limite resistente ou de colapso. O efeito do fogo, como elemento activo e prejudicial à resistência do elemento estrutural, foi determinado tendo-se verificado uma substancial diminuição das capacidades resistentes, devendo por isso as acções serem convenientemente determinadas e analisadas. No âmbito deste trabalho foram ainda estudadas as acções em estruturas sujeitas à acção do fogo, a variação das propriedades mecânicas e térmicas do aço com a temperatura e o comportamento não linear geométrico e material da estrutura. Tendo como objectivo o desenvolvimento de ensaios experimentais em vigas de perfil comercial, foi elaborada a candidatura de um projecto de Investigação e Desenvolvimento, intitulado “Lateral Buckling of Steel Beams Under Fire Conditions”, financiado pelo Ministério da Ciência e da Tecnologia, o que tornou possível a constituição de todo o equipamento que serviu de base a este trabalho. Neste caso construiu-se um “setup” com as vertentes térmica e estrutural necessárias para ensaiar estruturas em situação acidental de incêndio. Paralelamente foram desenvolvidos vários ensaios numéricos do fenómeno de encurvadura lateral a elevadas temperaturas com um programa de análise não linear geométrica e material, como são exemplo os programas SAFIR, ANSYS e Cosmos/M, os quais permitiram validar os restantes resultados e justificar a necessidade da revisão de algumas formulas simplificadas que o Eurocódigo 3 apresenta, nomeadamente as que dizem respeito à determinação da resistência de vigas à encurvadura lateral, em situação de incêndio. No final é apresentada a validação de uma proposta de cálculo simples para verificação de elementos estruturais à encurvadura, que se propõe em alternativa à proposta apresentada pelo Eurocódigo 3. In this thesis a numerical and experimental validation of the lateral torsional buckling phenomenon of steel I beams under fire conditions is presented. A set of experimental destructive tests were made in several I beams profiles for the buckling moment resistance determination. The fire effect as an active element may produce a severe reduction in structural strength. The numerical simulation of this phenomenon was done by means of a finite element code with non linear material and geometrical behaviour, based on elevated and constant temperatures. The structural actions under fire conditions, the material behaviour regarding its mechanical and thermal properties variation with temperature and the non linear behaviour of structures were also studied.. Having in mind the development of experimental tests in the commercial profiles IPE100, a research project “ Lateral Buckling of Steel I Beams Under Fire Condition” has been financed by the Science and Technology Portuguese Ministry, helping us to build a thermal and structural set up for this propose. In parallel, several numerical simulations had been done by means of the material and geometrical non linear finite element code SAFIR, as well as, with other commercial codes, ANSYS and CosmosM. This lead us to the justification and the needed of reviewing some simple formulas in Eurocode regarding the lateral buckling behaviour of structures under fire conditions. Finally a validation of a new proposal for a simple model in lateral torsional buckling under fire conditions is presented, different from that used in Eurocode, that seams to give unsafe results.

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Brown, Michael John. "The rapid load testing of piles in fine grained soils." Thesis, University of Sheffield, 2004. http://etheses.whiterose.ac.uk/10268/.

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The behaviour has been examined of piles installed in clay subject to a rapid load testing method known as the Statnamic test. The Statnamic method is easier and quicker to mobilise than a static test and is less complex to analyse than dynamic pile load tests. This investigation consisted of a laboratory study of the effect of the rate of loading on pile behaviour in clay and a field test of a pile in glacial clay to calibrate the findings of the laboratory study. The effects of penetration rate and Statnamic loading on model pile behaviour have been studied using an instrumented clay calibration chamber. The effect of rate of loading on the pile's capacity was quantified using constant rate of penetration tests (CRP) at different pile penetration rates. This allowed viscous soil damping characteristics to be determined and a new Statnamic analysis method incorporating rate dependant soil behaviour to be developed. This rate dependant behaviour can be represented by modification of a non-linear rate law proposed by Randolph & Deeks (1992). A field pile testing facility was developed in glacial till. To test the success of the new Statnamic analysis, a class A prediction of static pile behaviour from prototype pile load testing was undertaken. Encouraging results were obtained for the prediction of ultimate static pile behaviour, but the analysis method under predicted soil-pile stiffness. A soil inertial component was added to the analysis, based upon instrumentation readings, which improved the predicted static soil-pile stiffness. Results from prototype pile testing show that the stiffness during Statnamic and static load tests was very similar up to 50% of the ultimate static pile capacity. Thus, rapid load testing may be used for verification of pile settlements at working loads in clays. At the present level of understanding of testing in clays, rapid load pile tests should not be carried out in isolation. Ideally, tests should be used in conjunction with a static test that will allow back figured parameters to be derived for analysis.

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Tangvald, Lars. "Implementing LOD for physically-based real-time fire rendering." Thesis, Norwegian University of Science and Technology, Department of Computer and Information Science, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-8814.

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In this paper, I present a framework for implementing level of detail (LOD) for a 3d physically based fire rendering running on the GPU. While realistic fire rendering that runs in real time exists, it is generally not used in real-time applications such as game, due to the high cost of running such a rendering. Most research into the rendering of fire is only concerned with the fire itself, and not how it can best be included in larger scenes with a multitude of other complex objects. I present methods for increasing the efficiency of a physically based fire rendering without harming its visual quality, by dynamically adjusting the detail level of the fire according to its importance for the current view. I adapt and use methods created both for LOD and for other areas to alter the detail level of the visualization and simulation of a fire rendering. The desired detail level is calculated by evaluating certain conditions such as visibility and distance from the viewpoint, and then used to adjust the detail level of the visualization and simulation of the fire. The implementation of the framework could not be completed in time, but a number of tests were run to determine the effect of the different methods used. These results indicate that by making adjustments to the simulation and visualization of the fire, large boosts in performance are gained without significantly harming the visual quality of the fire rendering.

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Lane, R. "Studies of load transfer through an interphase in fibre reinforced composites." Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339964.

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Baroonian, A. "Theoretical and experimental investigation of fibre cement corrugated sheeting under load." Thesis, University of Surrey, 1986. http://epubs.surrey.ac.uk/843515/.

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The experimental performance together with the theoretical predictions of strains and deflections of thin fibre cement corrugated sheets are principally reported in this thesis. Existing theories of tensile behaviour of fibre reinforced cement are reviewed. Asbestos cement and alternative fibre reinforced cement technologies associated with these sheeting materials are discussed. Asbestos cement and polypropylene network reinforced cement corrugated sheeting have been tested under a variety of loading regimes and support conditions. Asbestos-free commercial products have also been tested. Finite element analyses based on the LUSAS system have been used to predict the shape of the uncracked load- deflection curves and deflection and strain profiles of various corrugated sheets with different geometrical profiles. Wetting and drying tests on uncracked asbestos cement and polypropylene network reinforced cement sheets have been carried out and a prediction made using the Lusas program of the warping stresses caused by moisture gradients. A new approach has been developed to predict the load-deflection curves and deflection profiles of semi-cracked and severely cracked polypropylene network reinforced cement sheets under various loading regimes. In this approach, cyclic loading characteristics of the tensile specimens were used to estimate the elastic moduli of the cracked composite for various numbers of cracks at two different load levels. Generally, the theoretical predictions show good agreement with the experimental results for uncracked and cracked sheets and hence the mathematical models could, with confidence, be used to assess the performance of a range of corrugated sheeting with various loading configurations.

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Beek, Wouter, Garcia Javier David Fernandez, and Ruben Verborgh. "LOD-a-lot: A single-file enabler for data science." ACM Press, 2017. http://epub.wu.ac.at/6492/1/LOD%2Da%2Dlot_SEMANTiCS2017.pdf.

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Many data scientists make use of Linked Open Data (LOD) as a huge interconnected knowledge base represented in RDF. However, the distributed nature of the information and the lack of a scalable approach to manage and consume such Big Semantic Data makes it difficult and expensive to conduct large-scale studies. As a consequence, most scientists restrict their analyses to one or two datasets (often DBpedia) that contain at most hundreds of millions of triples. LOD-a-lot is a dataset that integrates a large portion (over 28 billion triples) of the LOD Cloud into a single ready-to-consume file that can be easily downloaded, shared and queried with a small memory footprint. This paper shows there exists a wide collection of Data Science use cases that can be performed over such a LOD-a-lot file. For these use cases LOD-a-lot significantly reduces the cost and complexity of conducting Data Science.

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Khanal, Bikash. "Post Buckling of Non Sway Axially Restrained Columns Under Thermal(Fire) Loads." OpenSIUC, 2014. https://opensiuc.lib.siu.edu/theses/1543.

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The objective of this study was to numerically investigate the effects of slenderness ratios and end rotational restraints on the post-buckling behavior of non-sway columns. To study the effect of end restraints, numerical solutions were generated for three different support conditions, namely, hinged-hinged, fixed-hinged and fixed-fixed. Furthermore, for each of these support conditions, the effects of slenderness ratios on the post-buckling response were analyzed by considering the slenderness ratios of 50,125 and 200. Based on the numerical data presented in this thesis, the following conclusions can be made.  The unrestrained columns under mechanical loads do not exhibit any significant post-buckling strength.  Restrained Columns subjected to thermal loading undergo significantly smaller deformations in contrast to unrestrained columns, where deformations are relatively larger as the loads are increased only slightly above their critical levels.  The mechanical post-buckling response does not seem to depend on the slenderness ratios of the columns ;whereas the thermal post-buckling response depends on the slenderness ratios of the columns with the relative deformation decreasing with slenderness ratio at a given temperature ratio.  Post buckling behavior of columns subjected to mechanical loadings does not seem to change when the rotational restraints are added whereas in case of columns subjected to thermal loading, the post-buckling response depends on the rotational restraints at the ends of the column. o For a constant slenderness ratio, the deflection ratio was found out to be the smallest for the hinged-hinged column and largest for the fixed-fixed column subjected to thermal loads at a given temperature ratio.

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Klein, Mario, Frank Podlesak, Kevin Höfer, Holger Seidlitz, Colin Gerstenberger, Peter Mayr, and Lothar Kroll. "Advanced Joining Technologies for Load and Fibre Adjusted FRP-Metal Hybrid Structures." Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-177669.

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Multi-material-design (MMD) is commonly realized through the combination of thin sheet metal and fibre reinforced plastics (FRP). To maximize the high lightweight potential of the material groups within a multi-material system as good as possible, a material-adapted and particularly fibre adjusted joining technology must be applied. The present paper focuses on two novel joining technologies, the Flow Drill Joining (FDJ) method and Spin-Blind-Riveting (SBR), which were developed for joining heavy-duty metal/composite hybrids. Tests were carried out with material combinations which are significant for lightweight constructions such as aluminium (AA5083) and carbon fibre-reinforced polyamide in sheet thickness of 1.8 mm. The mechanical testing and manufacturing of those multi-material joints was investigated.

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Shrestha, Sujan. "POST BUCKLING RESPONSE OF SWAY COLUMNS UNDER MECHANICAL AND THERMAL (FIRE) LOADS." OpenSIUC, 2015. https://opensiuc.lib.siu.edu/theses/1623.

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AN ABSTRACT OF THE THESIS OF Sujan Shrestha, for the Master of Science degree in Civil Engineering, presented on March 3, 2015, at Southern Illinois University, Carbondale. TITLE: POST BUCKLING RESPONSE OF SWAY COLUMNS UNDER MECHANICAL AND THERMAL (FIRE) LOADS MAJOR PROFESSOR: Dr. Aslam Kassimali, Ph.D. The post-buckling response of sway columns under mechanical and thermal loadings are presented by using the geometrical nonlinear analysis. For thermal analysis, the columns are assumed to be fully restrained in their axial directions. The method of analysis uses Beam-Column theory which is based on an Eulerian (corotational) formulation. Numerical solutions are shown for the post-buckling response of sway columns. The numerical investigations of the geometrically nonlinear analysis of sway columns were carried out with three different boundary conditions of sway columns as suggested by AISC, under mechanical loading and temperature changes. The sway columns considered are the cases `c', `e' and `f' in Table C-A-7.1 of AISC Manual (2011). These were modeled and analyzed to predict the post-buckling response under the mechanical and thermal loads. Furthermore, for each of these support conditions, the effects of slenderness ratios on the post-buckling response were analyzed by considering the slenderness ratios of 50,125 and 200. Also, the effects on post-buckling strength were observed keeping the same slenderness ratios but varying rotational end conditions of sway columns. Many useful conclusions can be drawn from this study. The more important conclusions are: 1) As all unrestrained sway columns undergo excessive deformation under mechanical loading, they do not possess significant post-buckling strength once the loading reaches the buckling load. 2) All restrained sway columns undergo much smaller deformations under thermal loading as compared to mechanical loading; thus significant post-buckling strength is achieved even after reaching the buckling temperature. This post-buckling strength can be considered during the design of structures which will aid in safe and economical structures. 3) Slenderness ratios play an important role on post-buckling strength only in thermal analysis but not in mechanical analysis. Increase in slenderness ratio tends to decrease the post-buckling relative deformation of the columns under thermal loading but has no such effect under mechanical loading. 4) Rotational end conditions also play significant role on post-buckling strength during thermal analysis but not during mechanical analysis. Keeping the slenderness ratio constant and varying the rotational end conditions, the post-buckling strength of all sway columns remains same under mechanical loading but is different under thermal loading.

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RANGISETTY, PAVAN TEJA. "NONLINEAR RESPONSE OF UNIFORMLY LOADED AXIALLY RESTRAINED BEAMS UNDER THERMAL (FIRE) LOADS." OpenSIUC, 2016. https://opensiuc.lib.siu.edu/theses/1867.

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The nonlinear response of axially restrained beams under thermal loads is analyzed using the method of geometric nonlinear analysis. Numerical solutions are shown for both pre and post buckling response of beams. The analysis has been done for three different types of beams as given by AISC. These beams are referred from Table C-A-8.1 of AISC Manual (2010). The types of support conditions of the beams are hinged-hinged, fixed-hinged and fixed-fixed. All the beams were subjected to two levels of uniformly distributed loads with respect to their yield capacity along the length of the beam. For each of the beam support conditions, two slenderness ratios 50 and 100 were analyzed. Some of the important conclusions drawn in this study are: • The temperature amplification factors seem to be significantly smaller than the load amplifications given by AISC. • Two lengths of beams were studied in this research in which the amplification factor for the smaller length beam were found to be slightly larger than amplification factors for the longer beam due to the same temperature increase. • Two different load conditions were used in this thesis, one being a half of yield moment and the other is one-tenth of the yield moment. The amplification factors were higher for the lower loading (ie. one-tenth yield moment) as compared the higher loading (ie. one-half of yield moment).

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Kunkel, Julian Martin. "Towards automatic load balancing of a parallel file system with subfile based migration." [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:bsz:16-opus-74808.

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Tatarowicz, Aubrey Lynn. "Look-up tables : the benefit of enabling fine-grained routing and load balancing." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/66813.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 61-63).
Data volumes are exploding. It is essential to use multiple machines to store such large amounts of data. To address this explosion, storage systems like databases need to be distributed across many machines. Transactions that access a few tuples, often seen in web workloads such as Twitter, do not run optimally using traditional partitioning schemes [25]. Hence, increasing the number of machines often presents a bottleneck for workloads where each transaction accesses just a few tuples. Fine-grained partitioning can fix the scale out problem introduced by simplistic partitioning schemes. In this thesis, I introduce a design of a distributed query execution system that handles fine-grained partitioning using look-up tables. I introduce look-up tables, which is a mapping from a tuple attribute to a tuple back-end location such that fine grained partitioning can be supported. I show through both synthetic and real data that fine-grained partitioning enabled by look-up tables can increase throughput of a distributed database system. My goal is scale-out with the number of machines used in the distributed database. I show in my experiments that scale-out can be reached if an ideal partitioning can be created. I test my implementation on a Wikipedia data set. I show in this example a factor of three times better performance compared to the optimal hash partitioning scheme with eight back-ends and signs of continual scale-out with more machines. Through the use of large data sets and projecting my results onto even larger data sets, I show that look-up tables can be used to represent complex partitioning schemes for databases containing billions of tuples.
by Aubrey Lynn Tatarowicz.
M.Eng.

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Brajkovic, Jurica. "Evaluating investment in base load coal fired power plant using real options approach." Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/171553/.

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This thesis investigates the impact of uncertainty on investment in a coalfired power plant using a real options (RO) framework. It is organized in five chapters. In the first chapter I give an outline of the thesis. In Chapter 2 I review the background material. I describe the electricity sector in the pre- and post-liberalization periods and discuss the implication of the transition on investment in new generation capacity. Further, I analyze the mainstream approach to investment analysis used by the majority of electricity companies, the discounted cash flow (DCF) approach. Next, I describe an alternative approach for evaluating investments, RO. In Chapter 3 I perform an econometric analysis of dark spread prices. I select four different stochastic processes and fit them to the observed data. The goal is to find which of the four processes (arithmetic Brownian motion (ABM), Ornstein-Uhlenbeck (OU), Cox-Ingersoll-Ross (CIR) and the Schwartz one-factor process) can best describe the evolution of dark spread prices. The analysis shows that the CIR process is the most appropriate model to use to represent the evolution of dark spread prices. In Chapter 4 I evaluate an investment in a coal-fired power plant assuming the dark spread is the only source of uncertainty and using the stochastic processes for which I estimated parameters in Chapter 3. First I calculate the optimal investment threshold using a traditional budgeting approach based on the DCF principle. Following this, using the RO framework, I calculate the optimal investment threshold for the four stochastic processes. I conclude that one should use mean reverting process to model the investment decision but the choice of mean reverting process does not significantly affect the investment threshold values. In Chapter 5 I extend the analysis and model coal and electricity prices separately. Now the investment decision is affected by two factors: the price of electricity (output) and the price of coal (input). The goal of this chapter is to analyze whether this increase in complexity (going from a one-factor to a two-factor model) affects the result obtained in the previous chapter. Given the different dynamics of electricity and coal prices, I find that this approach enriches the investment analysis and gives additional insights. In particular, the higher the coal price, the greater the dark spread needs to be in order to undertake the investment. Finally, Chapter 6 concludes. The thesis contributes to the existing knowledge in several ways. RO have been applied to the electricity sector before, but this is the first time they have been applied to the evaluation of investment in a coal-fired power plant. Secondly, this is the first time that dark spread, electricity and coal prices are modeled for use in a RO analysis. Finally, the thesis provides a comparison of investment analysis for a coal-fired power plant using RO based on single and two state variables, which has not been carried out so far.

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Hood, Malcolm. "Monitoring fire fuel loads in fragmented vegetation cover types with remotely sensed data /." Title page, contents and abstract only, 1987. http://web4.library.adelaide.edu.au/theses/09AR/09arh777.pdf.

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Addor, Antonin. "Decomposition of Hourly Prices Forward Curves into Load Blocks." St. Gallen, 2008. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/04809687001/$FILE/04809687001.pdf.

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Silva, Anderson Peccin da. "Constitutive modelling of fibre-reinforced sands under cyclic loads." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/153323.

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Carregamentos cíclicos são causados de diversas maneiras, como tráfego de veículos, ondas, vento e terremotos. Nos últimos anos, particularmente, tem-se aumentado o número de estudos para este tipo de carregamento devido ao desenvolvimento da engenharia offshore. Além disso, técnicas de melhoramento de solos granulares têm sido empregadas para alterar as características dos solos naturais, com o objetivo de aumentar sua resistência e retardar - ou evitar - a ocorrência de liquefação. Alguns estudos anteriores desenvolveram leis constitutivas completas para areias reforçadas com fibras sob carregamento monotônico, mas não são encontrados na literatura trabalhos sobre a modelagem deste tipo de solos sob carregamentos cíclicos. Sendo assim, essa dissertação desenvolve e valida um novo modelo constitutivo capaz de avaliar o comportamento de solos granulares reforçados com fibras sob carregamento cíclico sob condições não-drenadas. Este modelo é baseado em dois modelos previamente desenvolvidos por Diambra et al. (2013) e Diambra e Ibraim (2014), que utilizam uma técnica de homogeneização para considerar a contribuição da areia e das fibras. O comportamento da areia segue o Modelo Severn-Trent Sand, proposto por Gajo e Muir Wood (1999). Uma vez estruturado o modelo e definido seu procedimento de cálculo, realiza-se uma análise paramétrica, a fim de demonstrar a influência de cada parâmetro das fibras e da areia no comportamento do compósito. Um fator de ajuste para levar em consideração a mudança nas forças interparticulares causada pelas fibras é proposto neste trabalho. Ao final, o modelo é calibrado com resultados experimentais e faz-se uma análise de suas competências e limitações. O processo de calibração mostrou que o modelo é capaz de capturar importantes tendências causadas pela inserção de fibras, como a redução nas deformações axiais e na geração de poropressões, retardando a ocorrência de liquefação. O modelo proposto mostrou-se mais efetivo em reproduzir o comportamento de areias fofas, ou seja, aquelas cujo estado de tensões se encontra acima da linha do estado crítico.
Cyclic loads are induced by several sources, such as traffic, waves, wind and earthquakes. Particularly in the last years, more attention has been given to such loading conditions due to the development of the offshore engineering. Additionally, ground improving techniques have been employed to alter the characteristics of natural soils in order to increase its strength and delay – or avoid – liquefaction. Previous studies have developed complete constitutive laws for fibre-reinforced sands under monotonic loading conditions, but no previous work on modelling granular soils under cyclic loading has been reported. Hence, this research develops and validates a new constitutive modelling which is capable to fully assess the behaviour of fibre-reinforced soils under cyclic loads for undrained conditions. This model is based on two previous models developed by Diambra et al. (2013) and Diambra and Ibraim (2014), which employed a homogenisation technique to scale sand and fibre contribution. The behaviour of the sand follows the Severn-Trent Sand Model proposed by Gajo and Muir Wood (1999). Once the model is structured and its calculation procedure is defined, a parametric analysis is carried out in order to show the influence of each fibre and sand parameter in the composite response. An adjustment factor to account for the change in the interparticle forces caused by the fibres is proposed. Finally, the model is calibrated with experimental results and an analysis of its competences and limitations is performed. The calibration process showed that the model is able to capture important trends caused by the fibre reinforcement, such as a reduction in axial strain and in pore pressure generation, delaying the occurrence of liquefaction. The proposed model was shown to be more effective in reproducing the response of loose sands, i.e. those whose stress states are above the critical state line.

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Dissertations / Theses on the topic 'Fire load'

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