| 1. |
- Silfwerbrand, Johan, et al.
(författare)
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Stor steg för brandsäkerheten
- 2011
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Ingår i: Betong. - : Svenska betongföreningen. - 1101-9190. ; :1, s. 37-39
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 2. |
- Anderson, Johan, et al.
(författare)
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Experimental comparisons in façade fire testing considering SP Fire 105 and the BS 8414‐1
- 2018
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Ingår i: Fire and Materials. - : Wiley. - 0308-0501 .- 1099-1018. ; 42:5
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Tidskriftsartikel (refereegranskat)abstract
- A comparison between full‐scale façade fire tests where SP Fire 105 and BS 8414‐1 were used regarding repeatability and the use of modeling to discern changes in the setups is presented. Two test series according to BS 8414‐1 were repeated outside using the same façade systems on 2 different days, whereas for the SP Fire 105 a set of common façade systems in Sweden were tested indoors. In particular, the results show that the wind around the test setup may have a significant impact on the tests and that the heat exposure to the façade surface will depend on the thickness of the test specimen where an increased temperature in front of the façade, and a decreased temperature on the façade 2.1 m above the fire room, is observed experimentally. The heat exposure to the test specimen varies to a more limited extent when an uncontrollable free burning fire source is used (in this study heptane and wood, respectively) and that this variation increases when wind is present.
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| 3. |
- Anderson, Johan, 1973-, et al.
(författare)
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Fire Safety of Façades
- 2017
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Façade fires do not occur often (in comparison to other major structure fires) but in recent years there have been a number of spectacular façade fires in high rise building such as the recent fire in Grenfell Tower, London.Under-ventilated compartment fires may cause flames to spill out of window openings impinging the façade, thus devastating façade fires may start on one floor leap-frogging to adjacent floors. It is therefore necessary to limit or delay fire spread to higher floors. Requirements built on large scale fire testing may decrease the risk of these types of fires provided that the building is constructed according to the specifications provided by the manufacturer. Different countries have different regulations and tests for façades. New materials and façade systems are continuously introduced which might call for an update of these tests and regulations.This report summarizes experimental and modelling efforts in characterizing the fire safety of façades using the Swedish SP Fire 105 and the British BS 8414 methods. Recent experimental results and modelling is presented exploring the variations in the fire exposure, fire load and the fuel used. The fire source and the heat exposure to the façade are characterized by additional temperatures measured by plate thermometers while some other aspects are only treated in the numerical study such as a change in fuel. It is found that the results from the BS 8414 are largely affected by wind and climate since the experimental test was performed outdoors, moreover fire spread on wooden façades is also briefly discussed.In order to obtain a deeper understanding of the test methods and the results CFD (Computational Fluid Dynamics) Modelling in FDS was used. The models were based on measured input parameters including uncertainties and an assessment of the impact of said uncertainties. The models could often reproduce the experimentally found temperatures qualitatively and quantitatively. A detailed discussion on the regulations and the tests that lead to the SP Fire 105 test method is also presented. Summaries of the façade testing methods and conditions in other European countries are presented in the appendices.Finally possible ways forward in updating the façade testing and regulations are discussed.
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| 4. |
- Anderson, Johan, et al.
(författare)
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Modelling of fire exposure in facade fire testing
- 2017
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Ingår i: Fire and Materials. - : John Wiley & Sons. - 0308-0501 .- 1099-1018. ; 42:5, s. 475-483
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, a comparative simulation study on 3 large‐scale facade testing methods, namely,the SP Fire 105, BS 8414‐1, and the ISO 13785‐2 methods, is presented. Generally goodcorrespondence between simulations and experimental data has been found, provided thatthermal properties of the facade material and heat release rates are known; however, thecorrespondence deviates in close proximity of the fire source. Furthermore, a statistical ensemblefor evaluating the effects stemming from uncertainty in input data is used. Here, it wasfound using this statistical ensemble that the variability was smaller in the ISO 13785‐2compared to the BS 8414‐1 method. The heat release rates (HRR) used in the simulations wereadopted from measurements except for the ISO method where the information in the standardwas used to approximate the HRR. A quantitative similarity between the HRR in the ISOmethod and the British method was found.
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| 5. |
- Anderson, Johan, et al.
(författare)
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Uncertainties in façade fire tests - Measurements and modeling
- 2016
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Ingår i: MATEC Web of Conferences. - : EDP Sciences.
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Konferensbidrag (refereegranskat)abstract
- In this paper a comparison between test and modelling results are performed for two large-scale façade fire testing methods, namely SP Fire 105 and BS 8414-1. In order to be able to compare tests and modelling the uncertainties have to be quantified both in the test and the modelling. Here we present a methodology based on deterministic sampling to quantify uncertainties in the modelling input. We find, in general good agreement between the models and the test results. Moreover, temperatures estimated by plate thermometers is indicated to be less sensitive to small variations in model input and is thus suitable for these kind of comparisons.
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| 6. |
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| 7. |
- Jansson McNamee, Robert, et al.
(författare)
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The function of intumescent paint for steel during different fire exposures
- 2016
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In the present study the behaviour of four intumescent systems for steel was investigated experimentally. The main purpose of the study was to determine the behaviour of the systems during different fire scenarios including standardized furnace testing, tests in cone calorimeter and ad hoc tests including ceiling jets and fire plumes. The experimental campaign shows that two of the investigated systems did perform very poorly in the furnace tests compared to what they were designed for, despite being the systems having the best swelling in the cone calorimeter tests. This highlights the importance of adhesion at high temperature for this type of systems. Since adhesion is crucial a more relevant evaluation for this type of systems ought to be a test where the flows around the specimen can be characterized and controlled, i.e. a ceiling jet or a fire plume scenario. This is especially important as steel protected with intumescent systems are often used in large open spaces where local fire plumes and ceiling jets are expected.Key words: intumescent paint, steel, alternative exposure
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| 8. |
- Johansson, Nils, et al.
(författare)
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Façade Fires in Swedish School Buildings
- 2013
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Ingår i: MATEC web of conferances. - : EDP Sciences. - 2261-236X. ; 9, s. 03006-03006
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Fires outside school buildings caused by arson are a major problem in Sweden. The initial fire source can involve rubbish or other types of combustibles that can be found at or sometimes brought to the school. As the external fire develops the flames will extend along the façade. If the building is a one-story building, which is a common construction in Swedish school buildings, the fire can spread to the attic and further on to the rest of the building. A large research project was initiated in 2008 by the Swedish Fire Research Board in order to reduce the number and consequences of arson fires in school buildings. In this paper an evaluation of some technical systems that can be used to mitigate consequences of exterior fires is presented. The evaluation includes a literature review, experimental studies and a cost-benefit analysis. The study showed that some systems have clear cost-benefit advantages for the protection of school buildings in places where a high fire frequency can be expected.
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| 9. |
- Johansson, Nils, et al.
(författare)
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Technical measures to prevent and mitigate the consequences of arson in school buildings
- 2014
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Ingår i: Fire Safety Science. - : International Association for Fire Safety Science. ; , s. 531-543
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Konferensbidrag (refereegranskat)abstract
- Fires in school buildings caused by arson are a major problem in Sweden and in particular are the costs of these fires disproportionately high compared to the costs of fires in buildings in general. The Swedish Research Board initiated a multidisciplinary project in order to reduce the number and consequences of arson fires in schools. Both technical and social aspects have been dealt within this project. In this paper an overview of the findings of the sub-project related to technical issues are presented. The goal and purpose of it has been to evaluate technical systems and engineering solutions to prevent and reduce the consequences of arson in school buildings. As part of this has a number of issues been considered including: identification of typical fire scenarios and design fires, an inventory of available technical systems and solutions, small- And real-scale experiments and an extensive cost-benefit analysis of a selection of technical systems.
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| 10. |
- Lange, David, et al.
(författare)
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Modelling of hollow core concrete construction exposed to fire
- 2016
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This report summarises the results of a project which was intended to study the response of hollow core and prestressed concrete construction exposed to fire. Two fires in the past 12 years highlighted the susceptibility of this type of construction to fire, a car park fire in Rotterdam and a department store fire in Vantaa. The car park fire has been extensively studied elsewhere and has led to much research on the response of hollow core construction exposed to fire. The department store fire has been less well reported.The report gives a short overview of these two fires, and then reports on a literature review of the response of prestressed and hollow core concrete construction exposed to fire. The comprehensive analyses carried out elsewhere are an excellent starting point for further study.The report then goes on to discuss the application of different concrete models to prestressed concrete construction. Other work reported elsewhere shows that results of modelling prestressed concrete construction exposed to fire is very susceptible to the concrete model which is used, and so finite element modelling of two fire tests of hollow core slabs is carried out to evaluate the impact of the concrete model on this type of construction. It is found that an explicit formulation of transient strain in concrete has a significant impact compared with an implicit formulation of transient strain, in the overall behaviour of the hollow core slab and also in the response of, e.g. the prestessing tendons.Finally, an analytical method for assessing the capacity of prestressed concrete construction under ambient conditions is extended to apply to hollow core slabs exposed to fire. This is used to compare the response of prestressed hollow core slabs to prestressed monolithic slabs exposed to fire and to study different parameters which influence the response and the capacity of hollow core units in fire.Based on the results of the analytical modelling, it can be seen that hollow core concrete construction experiences a far higher thermal gradient and resulting thermal moment than monolithic concrete construction. This is a result of the geometry of the cross section which effectively traps heat in the lower flange. This in turn leads to a faster loss of prestressing force on the cross section than in a monolithic concrete section. This contributes to a faster reduction in the ultimate moment of hollow core slabs compared with monolithic concrete construction.However changing the prestressing tendon depth has a significant effect on the evolution of the ultimate moment under fire exposure. A shallow tendon with little cover has higher capacity at ambient and under fire exposure for a short duration, whereas a tendon with a large amount of cover has a lower ambient capacity, but retains more of this capacity for longer under fire exposure.The analytical method which is proposed is not capable of capturing the nuances in behaviour and response of the finite element method which is reported, nevertheless it is useful in helping to understand the response of prestressed concrete construction exposed to fire. It may also be useful as a screening tool for evaluating the impact of different design options either in hollow core slabs themselves or when making choices in the design phase. However, both the analytical and the numerical modelling suffer from a lack of good quality experimental data which could be used for their evaluation and this should be considered in the future.Key words: prestressed concrete, hollow core slabs, fire, modelling
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