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  • 51.
    Carro-López, D.
    et al.
    Universidade da Coruña A, Spain.
    Fernandez, I.
    Chalmers University of Technology, Sweden.
    Williams Portal, Natalie
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    An old bridge transformed into a new one: Possible, recommendable?2019Inngår i: 20th Congress of IABSE, New York City 2019: The Evolving Metropolis - Report, International Association for Bridge and Structural Engineering (IABSE) , 2019, s. 951-956Konferansepaper (Fagfellevurdert)
    Abstract [en]

    There is an extensive network of reinforced concrete bridges that give service to roads, highways and railways. These structures where constructed with quality standards of the past, and they suffer of severe problems. Now we consider the idea of substituting them with structural elements with much longer service life. However, there is an important question to be addressed in this area: what to do with the existing infrastructure that would be demolished. Even more if we consider environmental issues. One good example of this recurrent problem could be found in the case of the Gullspång bridge (Sweden). It was constructed in 1935 and it was severely damaged with corrosion. The administration decided in the 2016 that no further repair would be done and that the bridge would be demolished and a new erected in substitution. A fraction of the concrete from the old bridge was crushed and processed to produce new aggregate. With this aggregate, using the coarse fraction, it was analyzed the structural effect of replacing natural aggregates with these recycled aggregates. The performance of the new structural elements was positive, and it seems that a high percentage of the natural aggregates could be replaced with recycled ones.

  • 52.
    Debuyser, Michael
    et al.
    Ghent University, Belgium.
    Sjöström, Johan
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Lange, David
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Honfi, Daniel
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Sonck, Dolphine
    Ghent University, Belgium.
    Belis, Jan
    Ghent University, Belgium.
    Behaviour of monolithic and laminated glass exposed to radiant heating2017Inngår i: Construction and Building Materials, ISSN 0950-0618, E-ISSN 1879-0526, Vol. 130, s. 212-229Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Glass is seeing a growing interest as a structural material as a result of its relatively good strength to weight ratio and the obvious aesthetic benefits of its use in buildings. However due to the sensitivity of glass to thermal shock and the considerably temperature-dependent behaviour of interlayer materials as a result of their visco-elastic nature, the mechanical behaviour of laminated glass will be severely influenced by exposure to fire. Relatively little research has been conducted in the past to study the response of load bearing structural glass, and laminated glass in particular to radiant heating. This paper represents an effort to try to understand the effects of through depth radiation absorption and temperature conduction through laminated glass with a view to ultimately developing a model for studying load bearing glass exposed to elevated temperatures, such as those that would be expected in a fire. The paper reports on an experimental research programme in which several monolithic and laminated glass configurations were exposed to a radiant heat flux to study the different phenomena that occur upon exposure to fire conditions, including the ratios of absorbed, transmitted and reflected heat flux to the incident heat flux. The paper then presents a numerical heat transfer model which is developed based on these experimental results and that is able to determine the evolution of the temperature profile as a result of a given incident heat flux. The effectiveness of the heat transfer model is demonstrated through comparison with the temperatures measured during the experimental work.

  • 53.
    Dederichs, Anne
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    NFSD Nordic Fire & Safety Days: Book of abstracts from the NFSD Nordic Fire & Safety Days 17-18 August in Copenhagen, Denmark2017Rapport (Annet vitenskapelig)
    Abstract [en]

    It is our pleasure to hand over to you this book of abstracts for the Nordic Fire & Safety

    Days 2017 organized by RISE, Research Institutes of Sweden in collaboration with the

    Technical University of Denmark, Lund University, Norwegian University of Science and

    Technology, University of Stavanger, Western Norway University of Applied Sciences,

    Lulea University of Technology and Iceland University as well as VTT Technical Research

    Centre of Finland Ltd, the Danish Institute of Fire and Security Technology and Aalborg

    University in Copenhagen.

    We are very proud to present the abstracts of 62 Nordic and international contributions

    in the present book of abstracts. The work demonstrates a significant scientific depth

    and societal relevance. The conference is a response to the extensive interest in the

    areas of fire and safety engineering in the Nordic countries in the past decades. As the

    programme and the abstracts show, the NFSD follow up on challenges with respect to

    safety dealing with aspects of fire and actions of the rescue service as well as human

    behavior and risk management. This year there is a special focus on fire safe furniture

    and the intervention of the rescue service.

    Fulltekst (pdf)
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  • 54.
    Dederichs, Anne
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Workshop on funding of research and development in the Nordic countries and Europe: report from the Nordic Fire & Safety Days 20182018Konferansepaper (Annet vitenskapelig)
  • 55.
    Dederichs, Anne
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Njå, OveUniversity Stavanger, Norway.Giuliani, LouisaDTU Technical University of Denmark, Denmark.Zawadowska, AlexandraRISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    BOOK OF PROCEEDINGS Nordic Fire & Safety Days 20182018Konferanseproceedings (Annet vitenskapelig)
    Fulltekst (pdf)
    fulltext
  • 56.
    Degerman, Helene
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Bram, Staffan
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Systemperspektiv på industriell brandsäkerhet- en studie av organisering och användbarhet i brandskyddet2019Rapport (Annet vitenskapelig)
    Abstract [en]

    Industrial fires are associated with many challenges and potentially large consequencesfor life, environment and property. The SEBRA project aimed to investigate preconditionsfor a well-functioning fire safety system, applying a systems perspective on workand safety. Three main themes were explored through field work on Swedish industrialworkplaces; (1) How do operations and the staff interact with fire safety installations ineveryday work, (2) What is the main focus of fire safety design, how is it conducted andhow do the end results affect fire safety and (3) What are the success factors behind positiveoutcomes from incidents where the personnel alone has dealt with fires.During the course of operations conflicts may occur between production and fire safetysolutions e.g. fire doors, detectors, alarm systems and procedures, sometimes to thepoint where fire protective routines or installations are bypassed. A common answer tosuch issues is to strengthen administrative barriers such as rules, safety information andtraining. However, in an industrial organization where resources are already strained,even more checks and routines will only run the risk of aggravating the problem at hand.When an industrial building is constructed there are no processes or methods that canprotect user needs in the design of fire protection. In construction, the main incitementis to minimize cost. When user adaptation is disregarded, costs are effectively transferredto the operational stage in the forms of more inefficient production and lower safety levels.The industry needs to develop ways of understanding and incorporating long-term operativeneeds in short-term construction projects, so that fire protection can be moreclosely fitted to the circumstances and demands of operative personnel

    Fulltekst (pdf)
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  • 57.
    Degerman, Helene
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Bram, Staffan
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Eriksson, Kerstin
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Resilient performance in response to the 2015 refugee influx in the Øresund region2018Inngår i: Safety and Reliability - Safe Societies in a Changing World - Proceedings of the 28th International European Safety and Reliability Conference, ESREL 2018, 2018, s. 1313-1318Konferansepaper (Fagfellevurdert)
    Abstract [en]

    September 2015 saw a sharp increase in the influx of refugees in the Øresund region. In this study, resilience defined as flexible adaptation was taken as a baseline to guide interviews with societal infrastructure actors and NGOs engaged in managing the situation. Different actors had different organisational preconditions that influenced their ability to adapt to the new situation. Among the strongest drivers behind resilient performance were the organisation’s ways of relating to established rules, regulations, procedures and processes, the way relationships were formed between people and hierarchical layers within the organisations, and the perceived value of the human operator and the human contribution within the organisational whole. These values, in turn, determined how the organisations shaped many of the basic conditions that allowed resilient performance to develop. In the study it was found, for public actors in particular, that the criteria necessary to adapt to the situation were not met by organisational structures and processes.

  • 58.
    Delin, Mattias
    et al.
    DeBrand Sverige AB, Sweden.
    Norén, Johan
    Briab Brand & Riskingenjörerna AB, Sweden.
    Ronchi, Enrico
    Lund University, Sweden.
    Kuklane, Kalev
    Lund University, Sweden.
    Halder, Amitava
    Lund University, Sweden.
    Fridolf, Karl
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Ascending stair evacuation: walking speed as a function of height2017Inngår i: Fire and Materials, ISSN 0308-0501, E-ISSN 1099-1018, Vol. 41, nr 5, s. 514-534Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    There is reason to believe that factors such as physical exertion and behavioural changes will influence the ascending walking speed and ultimately the possibility of satisfactory evacuation. To study these effects, a 2-year research project was initiated with the focus on effects of physical exertion on walking speeds, physiological performance and behaviours during long ascending evacuations. Two sets of experiments on human performance during ascending long stairs, with a height of 48 and 109 m, were performed. The results include aspects such as walking speeds, physical exertion (oxygen consumption, heart rates and electromyography data), perceived exertion and behavioural changes, showing that physical work capacity affects walking speeds in case of long ascending evacuation and should be considered while using long ascending evacuation. Analysis of both walking and vertical speeds is recommended because it provides additional insights on the impact of stair configuration on vertical displacement and the importance of not using the same value for walking speed for different stairs because the design of the stairs has an impact. The novel datasets presented in this paper are deemed to provide useful information for fire safety engineers both for assisting fire safety design as well as the calibration of evacuation modelling tools.

  • 59.
    Edelbro, Catrin
    et al.
    Luleå University of Technology, Sweden .
    Hulthén, Erik
    Chalmers University of Technology, Sweden.
    Clausen, Elisabeth
    Technical University of Clausthal, Germany.
    Tanner, David
    University of Limerick, Ireland.
    Herrera Herbert, Juan
    Universidad Politécnica de Madrid, Spain.
    Jonsson, Kristina
    LKAB, Sweden.
    Bealieu, Stephan
    RUSAL Aughinish Alumina, Ireland.
    Kamp, Aldert
    Delft University of Technology, The Netherlands.
    Försth, Michael
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    European Initiative on CDIO in Raw Material Programmes2017Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    One of five Knowledge and Innovation Communities (KICs), was launched in Europe in 2014 and has its focus on exploration, extraction, mineral processing, metallurgy, recycling and material substitution of raw materials. To reach the vision, where the European Union’s industrial strength is based on a cost-efficient, secure, sustainable supply and use of raw materials, a new generation of skilled people entering industry, universities and research needs to be developed. Today’s technical MSc graduates in raw materials and especially primary resources (i.e. exploration, extraction, mining and mineral processing and metallurgy) best suits large companies where they often act as specialists and experts. For small to medium enterprises as well as for our future engineers other skills than technical are necessary. As a part of the KIC Raw Materials, the education project “The implementation of CDIO in raw material programmes” started in 2016. The project focuses, during 2016-2017, on (WP1) faculty- and (WP2) pilot case development. There are no academic institutes in Europe that have yet applied CDIO for primary resource related MSc programmes. This paper describes an education project within the KIC Raw material and presents key outputs with implementing CDIO in mining and metallurgy related programmes.

    Fulltekst (pdf)
    fulltext
  • 60.
    Elmquist, Lennart
    et al.
    RISE - Research Institutes of Sweden, Material och produktion, SWECAST.
    Hall, S.
    Lund University, Sweden.
    Sjögren, Torsten
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Dartfeldt, Erik
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Skoglund, P.
    Scania CV AB, Sweden.
    Elfsberg, J.
    Scania CV AB, Sweden.
    Majkut, M.
    European Synchrotron Radiation Facility, France.
    Mechanical and structural characterization of cast iron using synchrotron light2018Inngår i: 73rd World Foundry Congress "Creative Foundry", WFC 2018 - Proceedings, 2018, s. 129-130Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The paper describes work done using synchrotron light to investigate the microstructure and how it behaves in 3D when a load is applied. Two different cast iron materials with different matrix structures and graphite morphologies were investigated; SiMo51, which is basically a spheroidal iron (SGI) alloyed with Si and Mo, and a lamellar graphite iron (LGI). The tensile test specimens were loaded in steps, at which x-ray tomography as well as 3DXRD measurements were made to characterize the microstructure. The result shows how the crack propagates and which path it takes through the materials. DVC was applied to analyze the strain fields. This work also shows how useful synchrotron experiments can be in the study of the mechanical behavior of cast iron.

  • 61.
    Engsig-Karup, Allan
    et al.
    DTU Technical University of Denmark, Denmark.
    Eskilsson, Claes
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Spectral element FNPF simulation of focused wave groups impacting a fixed FPSO-type body2019Inngår i: International Journal of Offshore and Polar Engineering, ISSN 1053-5381, Vol. 29, nr 2, s. 141-148Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A 3D fully nonlinear potential flow (FNPF) model based on an Eulerian formulation is presented. The model is discretizedusing high-order prismatic – possibly curvilinear – elements using a spectral element method (SEM) that has support foradaptive unstructured meshes. The paper presents details of the FNPF-SEM development, and a model is illustrated toexhibit exponential convergence for steep stream function waves to serve as validation. The model is then applied to the caseof focused waves impacting on a surface-piercing, fixed FPSO-like structure. Good agreement is found between numericaland experimental wave elevations and pressures.

  • 62.
    Engsig-Karup, Allan P.
    et al.
    DTU Technical University of Denmark, Denmark.
    Eskilsson, Claes
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety. Aalborg University, Denmark.
    Spectral element FNPF simulations of focused wave groups impacting a fixed FPSO2018Inngår i: Proceedings of the Twenty-eighth (2018) International Ocean and Polar Engineering Conference, The International Society of Offshore and Polar Engineering , 2018, s. 1443-1450Konferansepaper (Fagfellevurdert)
    Abstract [en]

    For  the assessment of experimental measurements of focused wave groups impacting a surface-piecing fixed structure, we present a new Fully Nonlinear Potential Flow (FNPF) model for simulation of unsteady water waves. The FNPF model is discretized in three  spatial dimensions (3D) using high-order prismatic - possibly curvilinear - elements using a  spectral  element  method (SEM) that has support for adaptive unstructured meshes. This  SEM-FNPF model is based on an Eulerian formulation and deviates from past works in that a  direct discretization of the Laplace problem is used making it straightforward to handle  accurately floating structural bodies of arbitrary shape. Our objectives are; i) present detail of a new SEM modelling developments and ii) to consider its application to address a wave-body interaction problem for nonlinear design waves and their interaction with a model-scale fixed Floating Production, Storage and Offloading vessel (FPSO).  We first reproduce  experimental measurements for focused design waves that represent a probably extreme  wave event for a sea state represented by a wave spectrum and seek to reproduce these measurements in a numerical wave tank. The validated input signal based on measurements is then generated in a NWT setup that includes the FPSO and differences in the signal caused by nonlinear diffraction is reported.

  • 63.
    Engsig-Karup, Allan P
    et al.
    DTU Technical University of Denmark, Denmark.
    Monteserin, Carlos
    DTU Technical University of Denmark, Denmark.
    Eskilsson, Claes
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety. Aalborg University, Denmark.
    A mixed Eulerian-Lagrangian spectral element method for nonlinear wave interaction with fixed structures2019Inngår i: Water Waves, ISSN 2523-367X, Vol. 1, s. 315-342Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present a high-order nodal spectral element method for the two-dimensional simulationof nonlinearwaterwaves. The model is based on themixed Eulerian–Lagrangian(MEL) method. Wave interaction with fixed truncated structures is handled usingunstructured meshes consisting of high-order iso-parametric quadrilateral/triangularelements to represent the body surfaces as well as the free surface elevation. A numericaleigenvalue analysis highlights that using a thin top layer of quadrilateral elementscircumvents the general instability problem associated with the use of asymmetricmesh topology.We demonstrate howto obtain a robustMELscheme for highly nonlinearwavesusing an efficient combination of (i) global L2 projectionwithout quadratureerrors, (ii) mild modal filtering and (iii) a combination of local and global re-meshingtechniques. Numerical experiments for strongly nonlinear waves are presented. Theexperiments demonstrate that the spectral element model provides excellent accuracyin prediction of nonlinear and dispersive wave propagation. The model is also shownto accurately capture the interaction between solitary waves and fixed submerged andsurface-piercing bodies. The wave motion and the wave-induced loads compare wellto experimental and computational results from the literature.

  • 64.
    Erikson, Martin G
    et al.
    University of Borås, Sweden.
    Eriksson, Anita
    University of Borås, Sweden.
    Johnson, Erland
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Nagy, Agnes
    University of Borås, Sweden.
    Richards, Tobias
    University of Borås, Sweden.
    A conceptual model of how research can influence student development2017Inngår i: Connecting Higher Education International perspectives on research-based education BOOK OF ABSTRACTS. Tues 27 June to Wed 28 June 2017. London, United Kingdom, 2017, s. 71-72, artikkel-id 86Konferansepaper (Fagfellevurdert)
  • 65.
    Eriksson, Kerstin
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Safety.
    Framework for crisis planning: Four required areas for developing a learning process2016Inngår i: Journal of Emergency Management, ISSN 1543-5865, Vol. 13, nr 6, s. 519-531Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To outline a framework for preparedness planning at the organizational level.The study is based on a content analysis of research literature as well as an analysis of interviews with six preparedness planners working in Swedish local authorities.The study setting included Swedish local authorities of different sizes.The participants are preparedness planners responsible for coordinating crisis management work in Swedish local authorities. The study includes preparedness planners with different backgrounds, education, experiences, and gender.A presentation of 19 factors of preparedness planning identified in the literature and a discussion around how preparedness planners perceive those factors.The main outcome measures are knowledge about how both researcher and practitioner understand and argue around different factors of preparedness planning.The result of this study is a framework for preparedness planning. As preparedness planning ought to be a learning process, the presented framework builds on four areas connected to learning: prerequisites for preparedness planning, who should be involved, what is to be learned, and how should the work be shaped.The analysis of factors identified in the literature and also in the interviews with preparedness planners illustrates that the four areas connected to learning are required for developing a preparedness planning process.

  • 66.
    Eskilsson, Claes
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety. Aalborg University, Denmark.
    Palm, Johannes
    Chalmers University of Technology, Sweden.
    Simulations of floating wave energy devices using adaptive mesh refinement2019Inngår i: Advances in Renewable Energies Offshore / [ed] C. Guedes Soares, 2019, s. 431-438Konferansepaper (Fagfellevurdert)
    Abstract [en]

    CFD simulations of floating wave energy converters are computationally very heavy. This paper deals with a straightforward attempt to cut down on the computational effort by using adaptive mesh refinement (AMR). We investigate the use of AMR for simulations involving floating bodies inside the open-source finite volume framework OpenFOAM. A simple error indicator based on the pressure jump over cell faces is used to drive the AMR. First the use of the error indicator is illustrated for propagation of a very steep stream function wave. Then the AMR technique is applied to two cases of floating bodies: (i) a floating box and (ii) a bottom reacting point-absorber. As expected the AMR significantly reduce the number of cells in the computational meshes and subsequently lower the  computational effort.

  • 67.
    Evegren, Franz
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Fire risk assessment of alternative ship design2017Inngår i: Ships and Offshore Structures, ISSN 1744-5302, E-ISSN 1754-212X, s. 1-6Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The procedure to evaluate fire safety of alternative ship design solutions, described in MSC/Circ.1002, has been found insufficient for novel and large scopes. In this paper, it is analysed with regards to function and applicability as a risk-based assessment procedure. Deficiencies are addressed based on risk assessment research and involvement in over a dozen performed assessments. Clarified are inconsistencies in the fire safety regulations, which must be considered particularly during identification of hazards. It is also suggested that affected safety functions are evaluated separately if possible and that the assessment sophistication is adapted to the scope of introduced hazards; four levels to perform parts of or the whole assessment are proposed.

    Fulltekst (pdf)
    fulltext
  • 68.
    Evegren, Franz
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Fire safety and FRP composite structures in maritime applications2017Inngår i: Proceedings of the Energy, Material & Nanotechnology Meeting on Smart & Multifunctional Material - ENM-SMM, 2017Konferansepaper (Annet vitenskapelig)
    Fulltekst (pdf)
    fulltext
  • 69.
    Evegren, Franz
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    proFLASH: Methanol fire detection and extinguishment: SP Rapport 2017:222017Rapport (Annet vitenskapelig)
    Abstract [en]

    Stricter emission requirements have led to ship operation on low flashpoint fuels, such as liquefied natural gas and methanol. These differ in many ways from traditional fuels (e.g. heavy fuel oil and marine gas oil), but requirements and guidelines for fire detection and extinguishment have been sparse. This was addressed in the proFLASH project, first theoretically and then experimentally. This report documents the experimental part of the project, focusing on methanol, and gives technical guidance for fire detection and extinguishing systems. It was for example concluded that methanol flames exhibit similar radiation to ethanol in the IR spectrum, despite limited observability in the visual spectrum. Approved IR flame detectors (tested against ethanol) are thereby likely suitable to detect methanol fire; tested detectors could even detect fully obstructed methanol fire. The design concentration of carbon dioxide gas fire-extinguishing systems should be increased from 40 % to 55 % to achieve the same safety margin for methanol as for traditional fuels. The primary extinguishing mechanism of a water-based fire-extinguishing system used against methanol is dilution, but almost 90 % water may be necessary for extinguishment. Furthermore, dilution makes the methanol flames increasingly invisible. It is recommended to use alcohol resistant foam injection with fixed water-based extinguishing systems, since this significantly reduces the time required for extinguishment. The effectiveness of the system depends on the foam/water application rate. Hence, a higher discharge rate is more effective and a concealed pool is difficult to extinguish. In different compartment fire test scenarios, water-spray with foam injection was more effective against methanol than water-spray without foam against standardized fuels. High and low pressure water mist performed better than water spray against standardized fuels but worse against methanol (with foam injection).

    Fulltekst (pdf)
    fulltext
  • 70.
    Evegren, Franz
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    SP Technology develop next generation of fire-safe island ferries for use between Sweden and Denmark2014Inngår i: International Fire Buyer, Vol. 26, nr 2, s. 52-53Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 71.
    Evegren, Franz
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Hertzberg, Tommy
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Fire safety regulations and performance of fibre-reinforced polymer composite ship structures2017Inngår i: Journal of Engineering for the Maritime Environment (Part M), ISSN 1475-0902, E-ISSN 2041-3084, Vol. 231, nr 1, s. 46-56Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents a procedure for how to relate fire performance of fibre reinforced polymer (FRP) composite structures to the fire safety regulations in SOLAS II-2. It can be used as basis when performing a fire risk assessment to demonstrate that the degree of safety is at least equivalent to that provided by prescriptive requirements. A key issue is that requirements and test methods are based on a use of steel structures, which requires seeking the safety level implied by the regulations. This was demonstrated for the regulations and introduced hazards affecting the growth stage of a fire. The safety implied by regulations was related to fire performance of FRP composite by reference to fire tests involving typical materials and some relevant safety measures. Ignition was described as uncritical whilst the fire growth on an FRP composite surface can be rapid. Flammability requirements are generally not achieved by an untreated panel but different means can be used for protection. A fire protective coating can be used to prevent ignition and sprinkler is effective both for fire prevention and extinguishment on interior and external surfaces. For interior spaces it can be relevant with a coating or thermal insulation also to hinder increased generation of smoke and toxic gases during fire evacuation. In total it is shown that fire hazards during the fire growth stage are manageable and a foundation is lain out for a well-structured fire risk assessment.

  • 72.
    Evegren, Franz
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Rahm, Michael
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Fire protection of FRP composite ship balconies2016Inngår i: Proceedings of the 11th International Conference on Sandwich Structures, 2016Konferansepaper (Fagfellevurdert)
    Fulltekst (pdf)
    fulltext
  • 73.
    Fan, Chuan Gang
    et al.
    University of Science and Technology of China, China; Hefei University of Technology, China.
    Ji, Jie
    University of Science and Technology of China, China.
    Li, Ying Zhen
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Ingason, Haukur
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Sun, Jin Hua
    University of Science and Technology of China, China.
    Experimental study of sidewall effect on flame characteristics of heptane pool fires with different aspect ratios and orientations in a channel2017Inngår i: Proceedings of the Combustion Institute, ISSN 1540-7489, E-ISSN 1873-2704, Vol. 36, nr 2, s. 3121-3129Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of small scale tests was conducted to investigate the influence of sidewall on flame characteristics of heptane pool fires in a channel, considering pool shape (aspect ratio: 1, 2, 4 and 8) and pool orientation relative to sidewall. Distance between fire and sidewall was changed systematically. Both transverse flame development (along the direction of channel width) and longitudinal flame development (along the direction of channel length) were recorded by digital video. Results show that for a fixed fire location, the heat release rate increases with the increasing pool aspect ratio (namely a larger pool perimeter), which indicates more air entrainment and more intense combustion. In wall fire cases, when the long pool rim is perpendicular with channel sidewall, the flame can obtain more air entrainment with a weaker boundary restriction from the sidewall, compared to the case with the long pool rim being parallel with sidewall. Comparison of some previously established correlations based on various experimental conditions with our test results is made. Due to the fact without considering sidewall effect and fuel shape on the air entrainment of fire plume, the classic correlations need to be further improved. Therefore, an integral flame length model considering both sidewall effect and fuel shape is developed, which correlates well with all the data from cases with various pool positions, orientations and aspect ratios. © 2016 The Combustion Institute. Published by Elsevier Inc.

  • 74.
    Fink, Gerhard
    et al.
    Aalto University, Finland.
    Honfi, Daniel
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Kohler, Jochen
    NTNU Norwegian University of Science and Technology, Norway.
    Dietsch, Philipp
    Technical University of Munich, Germany.
    Basis of Design Principles for Timber Structures: A state-of-the-art report by COST Action FP1402 / WG 12018Bok (Annet vitenskapelig)
  • 75.
    Flansbjer, Mathias
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Lindqvist, Jan Erik
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Meso Mechanical Study of Cracking Process in Concrete Subjected toTensile Loading2018Inngår i: Nordic Concrete Research, ISSN 0800-6377, Vol. 59, nr 2, s. 13-29Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    This project focused on how the cracking process in concrete is influenced by both the micro and meso structures of concrete. The aim was to increase knowledge pertaining to the effect of critical parameters on the cracking process and how this is related to the material's macroscopic properties. A methodology based on the combination of different experimental methods and measuring techniques at different scales was developed. Crack propagation during tensile loading of small-scale specimens in a tensile stage was monitored by means of Digital Image Correlation (DIC) and Acoustic Emission (AE). After testing, crack patterns were studied using fluorescence microscopy.

  • 76.
    Flansbjer, Mathias
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Lindqvist, Jan Erik
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Methodology for Mesomechanical Study of Concrete Material2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This project focuses on detailed studies of how the cracking process in concrete is influenced by the concrete micro- and mesostructure. The aim is to increase knowledge of how critical parameters affect the cracking process and how this is related to the material's macroscopic properties. A methodology based on the combination of different experimental methods and measuring techniques at different scale levels has been developed. Crack propagation during tensile loading of small-scale specimens in a tensile stage was monitored by means of Digital Image Correlation (DIC) and Acoustic Emission (AE). After the test, crack patterns were studied using fluorescence microscopy.

  • 77.
    Flansbjer, Mathias
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Williams Portal, Natalie
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    3D Analysis of Strains in Fibre Reinforced Concrete Using X-Ray Tomography and Digital Volume Correlation2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In fibre reinforced concrete (FRC), understanding the underlying interaction mechanisms between discrete fibres and the surrounding concrete matrix can lead to the optimization of the fibre-matrix combination. This paper presents the initial development of a method enabling the analysis of this given interaction on ameso-mechanical level. The method is such that volume images are initially captured using X-ray Computed Tomography (XCT) on small-scale FRC specimens under loading which are thereafter analysed to measure full 3D strainand deformation via Digital Volume Correlation (DVC). It is anticipated that the method developed in this project can be a useful tool for the developmentof new innovative and high performance FRC.

  • 78.
    Flansbjer, Mathias
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Williams Portal, Natalie
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Hall, Stephen
    Lund University, Sweden.
    Engqvist, Jonas
    Lund University, Sweden.
    Analysis of Failure Modes in Fiber Reinforced Concrete Using X-rayTomography and Digital Volume Correlation2018Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Pull-out mechanisms for different common steel fibers were investigatedusing adapted pull-out tests performed in-situ in an x-ray micro tomograph(µXRT). High-resolution volume images from the µXRT scans enable clearvisualization of aggregates, pores, the fiber and the fiber-matrix interface.Furthermore, the natural density speckle pattern from aggregate distributionand pores was found suitable for Digital Volume Correlation (DVC) analysis.From the DVC results it was possible to visualize and quantify the straindistribution in the matrix around the fiber at the different load levels up tofinal failure, being marked by either pull-out or fiber rupture. This studydemonstrates that strain measurements within the concrete matrix can beobtained successfully using µXRT imaging and DVC analysis, which leads to anincreased understanding of the interaction mechanisms in fibre reinforcedconcrete under mechanical loading.

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  • 79.
    Flansbjer, Mathias
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Williams Portal, Natalie
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Hall, Stephen
    Lund University, Sweden.
    Engqvist, Jonas
    Lund University, Sweden.
    Analysis of Fiber-matrix Interaction in FRC using X-ray Tomography and Digital Volume Correlation2019Inngår i: proc. of 10th International Conference on Fracture Mechanics of Concrete and Concrete Structures (FraMCoS-X), Bayonne, France: International Association of Fracture Mechanics for Concrete and Concrete Structures , 2019, , s. 8Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Fiber pull-out is generally considered to be the dominating failure mechanism in fiber reinforced concrete (FRC). Accordingly, pull-out tests are typically performed to characterize the fiber-matrix interaction. However, little direct insight can be gained on the actual mechanisms ofthe pull-out from such a test. Deeper understanding could however be gained through the addition of non-destructive techniques to pull-out tests to enable the visualization and quantification of the mechanical interaction. Pull-out mechanisms for different common steel fibers were investigated using adapted pull-out tests performed in-situ in an X-ray micro tomography (µXRT). High resolution volume images from the µXRT scans enable clear visualization of aggregates, pores, fiber and fiber-matrix interface. Furthermore, the natural density speckle pattern from aggregate distribution and pores was found to be suitable for Digital Volume Correlation (DVC) analysis. From the DVC results it was possible to visualize and quantify the strain distribution in the matrix around the fiber at different load levels up to final failure, being marked by either pull-out or fiber rupture. The load transfer mechanism was initially dominated by shear along the fiber. As the load increased, slip occurred in the end-hook region and mechanical locking became the governing mechanism. This study demonstrates that strain measurements within the concrete matrix and passive end-slip can be obtained successfully using µXRT imaging and DVC analysis, which leads to an increased understanding of the interaction mechanisms in fiber reinforced concrete under mechanical loading.

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  • 80.
    Flansbjer, Mathias
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Williams Portal, Natalie
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Vennetti, Daniel
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Verification of the structural performance of textile reinforced reactive powder concrete sandwich facade elements2019Inngår i: Applied Sciences, E-ISSN 2076-3417, Vol. 9, nr 12, artikkel-id 456Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    As a part of the SESBE (Smart Elements for Sustainable Building Envelopes) project, non-load bearing sandwich elements were developed with Textile Reinforced Reactive Powder Concrete (TRRPC) for outer and inner facings, Foam Concrete (FC) for the insulating core and Glass Fiber Reinforced Polymer (GFRP) continuous connectors. The structural performance of the developed elements was verified at various levels by means of a thorough experimental program coupled with numerical analysis. Experiments were conducted on individual materials (i.e., tensile and compressive tests), composites (i.e., uniaxial tensile, flexural and pull-out tests), as well as components (i.e., local anchorage failure, shear, flexural and wind loading tests). The experimentally yielded material properties were used as input for the developed models to verify the findings of various component tests and to allow for further material development. In this paper, the component tests related to local anchorage failure and wind loading are presented and coupled to a structural model of the sandwich element. The validated structural model provided a greater understanding of the physical mechanisms governing the element's structural behavior and its structural performance under various dead and wind load cases. Lastly, the performance of the sandwich elements, in terms of composite action, was shown to be greatly correlated to the properties of the GFRP connectors, such as stiffness and strength

  • 81.
    Flansbjer, Mathias
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Williams Portal, Natalie
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Vennetti, Daniel
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Samhällsbyggnad, CBI Betonginstitutet.
    Composite Behaviour of Textile Reinforced Reactive Powder Concrete Sandwich Façade Elements2018Inngår i: International Journal of Concrete Structures and Materials, ISSN 1976-0485, E-ISSN 2234-1315, Vol. 12, nr 1, artikkel-id 71Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Within the EC funded project smart elements for sustainable building envelopes, carbon textile reinforcement was incorporated into reactive powder concrete, namely textile reinforced reactive powder concrete (TRRPC), to additionally improve the post-cracking behaviour of the cementitious matrix. This high-performance composite material was included as outer and inner façade panels in prefabricated and non-load bearing sandwich elements along with low density foamed concrete (FC) and glass fibre reinforced polymer continuous connecting devices. Experiments and finite element analysis (FEA) were applied to characterize the structural performance of the developed sandwich elements. The mechanical behaviour of the individual materials, components and large-scale elements were quantified. Four-point bending tests were performed on large-scale TRRPC-FC sandwich element beams to quantify the flexural capacity, level of composite action, resulting deformation, crack propagation and failure mechanisms. Optical measurements based on digital image correlation were taken simultaneously to enable a detailed analysis of the underlying composite action. The structural behaviour of the developed elements was found to be highly dependent on the stiffness and strength of the connectors to ensure composite action between the two TRRPC panels. As for the FEA, the applied modelling approach was found to accurately describe the stiffness of the sandwich elements at lower load levels, while describing the stiffness in a conservative manner after the occurrence of connector failure mechanisms. © 2018, The Author(s).

  • 82.
    Gall, Dan
    et al.
    University of Gothenburg, Sweden.
    Pushp, Mohit
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Davidsson, Kent O.
    RISE - Research Institutes of Sweden, Samhällsbyggnad, Energi och cirkulär ekonomi.
    Pettersson, Jan B. C.
    University of Gothenburg, Sweden.
    Online Measurements of Alkali and Heavy Tar Components in Biomass Gasification2017Inngår i: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 31, nr 8, s. 8152-8161Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Tar and alkali metal compounds are released during biomass gasification and have a major impact on the operation and performance of gasification processes. Herein we describe a novel method for characterization of alkali and heavy tar compounds in the hot product gas formed during gasification. Gas is continuously extracted, cooled and diluted, which results in condensation of tar and alkali into aerosol particles. The thermal stability of these particles is subsequently evaluated using a volatility tandem differential mobility analyzer (VTDMA) method. The technique is adopted from aerosol science where it is frequently used to characterize the thermal properties of aerosol particles. Laboratory studies show that pure and mixed alkali salts and organic compounds evaporate in well-defined temperature ranges, which can be used to determine the chemical composition of particles. The performance of the VTDMA is demonstrated at a 4 MWth dual fluidized bed gasifier using two different types of online sampling systems. Alkali metal compounds and a wide distribution of heavy tar components with boiling points above 400°C are observed in the product gas. Implications and potential further improvements of the technique are discussed.

  • 83.
    Gall, Dan
    et al.
    University of Gothenburg, Sweden.
    Pushp, Mohit
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Larsson, Anton
    Göteborg Energi AB, Sweden.
    Davidsson, Kent
    RISE - Research Institutes of Sweden, Samhällsbyggnad, Energi och cirkulär ekonomi.
    Pettersson, Jan B. C.
    University of Gothenburg, Sweden .
    Online Measurements of Alkali Metals during Start-up and Operation of an Industrial-Scale Biomass Gasification Plant2018Inngår i: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 32, nr 1, s. 532-541Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Alkali metal compounds may have positive influences on biomass gasification by affecting char reactivity and tar reforming but may also disturb the process by formation of deposits and agglomerates. We herein present results from online measurements of alkali compounds and particle concentrations in a dual fluidized bed gasifier with an input of 32 MWth. A surface ionization detector was used to measure alkali concentrations in the product gas, and aerosol particle measurement techniques were employed to study concentrations and properties of condensable components in the gas. Measurements were performed during start-up and steady-state operation of the gasifier. The alkali concentration increased to approximately 200 mg m-3 when fuel was fed to the gasifier and continued to rise during activation of the olivine bed by addition of potassium carbonate, while the alkali concentration was in the range from 20 to 60 mg m-3 during steady-state operation. Addition of fresh bed material and recirculated ash had noticeable effects on the observed alkali concentrations, and K2CO3 additions to improve tar chemistry resulted in increased levels of alkali in the product gas. Addition of elemental sulfur led to reduced concentrations of CH4 and heavy tars, while no clear influence on the alkali concentration was observed. The study shows that alkali concentrations are high in the product gas, which has implications for the fluidized bed process, tar chemistry, and operation of downstream components including coolers, filters, and catalytically active materials used for product gas reforming.

  • 84.
    Gehandler, Jonatan
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    The theoretical framework of fire safety design: Reflections and alternatives2017Inngår i: Fire safety journal, ISSN 0379-7112, E-ISSN 1873-7226Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This article aims to contribute to discussions and reflections upon the practice and theory of fire safety design. Are we reaching the results we want by the best available means? The theoretical framework of fire safety design is today restricted by a linear design process where mainly quantitative data and methods matters. A deterministic approach to safety ignores the decision-making context and considers each objective in isolation. Alternative methods for the fire safety design could view the design work as an iterative problem solving process between the designers and the stakeholders. Then decision making theory can be applied to solve the problem. In the iterative process key objectives are identified and the problem and its solutions are being reframed, creative inherently safer (cannot fail) and fail safe (forgiving to errors) alternatives are initially aimed at. Design should further embrace a function-centred view of the human-technology-structure system. A utilitarian evaluation that includes also qualitative factors can identify the best trade-offs between conflicting objectives. With a diversity of perspectives on fire safety design, the field of fire safety will be strengthened and be able to assist a rapidly changing world.

  • 85.
    Gehandler, Jonatan
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Ingason, Haukur
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Principer och strategier för ventilation vid brand i undermarksanläggningar2018Rapport (Annet vitenskapelig)
    Abstract [en]

    The report describes different underground systems including mines and tunnels during construction (tunneling). The key factors that affect fire development in underground systems are described. Proposal and recommendations for ventilation strategies in case of fire are given. The report covers both fuel- and ventilation-controlled fires. In general, a minimal ventilation limits the fire growth and may even inert the fire through ascended smoke. A minimal ventilation also contributes to improved conditions for a first fire extinguishing attempt and evacuation.

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  • 86.
    Gehandler, Jonatan
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Karlsson, Peter
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Vylund, Lotta
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Risks associated with alternative fuels in road tunnels and underground garages2017Rapport (Annet vitenskapelig)
    Abstract [en]

    Due to environmental considerations, much current transportation policy development is aimed at increasing usage of renewable energy sources. These include gaseous fuels such as LPG, methane, and hydrogen, along with electricity. This research project focused on a literature review that was intended to research the risks involved in using alternative fuels in road tunnels and underground garages. Gaseous fuels and electric vehicles pose new risks that we, due to our greater familiarity with liquid fuels, are unused to. The greatest of these relate to gaseous fuels and pressure-vessel explosions, and the release of toxic gases such as hydrogen fluoride from Li-ion batteries undergoing thermal runaway. Two workshops were organised to obtain feedback from stakeholders and initiate discussion regarding the issue. Future research, risk-reducing measures, rescue service guidance, and changes to regulations and guidelines are discussed and proposed in this report.

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  • 87.
    Gehandler, Jonatan
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Lönnermark, Anders
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    CNG vehicle containers exposed to local fires2019Rapport (Annet vitenskapelig)
    Abstract [en]

    Fuels with a high energy density have contributed to the development of modern communities. On the other hand, fuels contain energy that, during some conditions, can result in incidents, not least within transportation. CNG vehicles are designed according to safety standards of UNECE, including events such as fire. In case of a fire a thermally activated Pressure Relief Device (TPRD) should empty the container before a pressure vessel explosion potentially can occur. CNG tanks are according to UNECE regulation 110 tested against a 1.65 m long pan fire. However, local fires are not included in these tests. This report presents fire tests of CNG containers performed both with a UNECE compatible fire source and with a local fire source. Any pressure vessel explosion and jet flames were characterized for two different types of CNG containers, namely steel and composite. In five out of six tests the safety of the CNG containers prevailed also in the event of a local (0.24 m by 0.24 m) pan fire, meaning that no pressure vessel explosion occurred. In real vehicle fires, where the fire extends from its local characteristics to a more developed fire that expose the CNG containers to a larger extent, these tests support that TPRDs most likely will activate. The experience from running these test series call for that the fire source should be more accurately defined with regards to fuel and dimensions and a local fire should be included in the UNECE Regulation 110.

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    RISE CNG container fire tests
    Download (mp4)
    RISE CNG steel tank fire tests (3 cameras)
    Download (mp4)
    RISE CNG composite tank fire tests (3 cameras)
  • 88.
    Girardin, Bertrand
    et al.
    UMR CNRS 8207 ENSCL, France.
    Fontaine, Gaelle
    UMR CNRS 8207 ENSCL, France.
    Duquesne, Sophie
    UMR CNRS 8207 ENSCL, France.
    Försth, Michael
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety. Luleå University of Technology, Sweden.
    Bourbigot, Serge
    UMR CNRS 8207 ENSCL, France.
    Measurement of kinetics and thermodynamics of the thermal degradation for flame retarded materials: Application to EVA/ATH/NC2017Inngår i: Journal of Analytical and Applied Pyrolysis, ISSN 0165-2370, E-ISSN 1873-250X, Vol. 124, s. 130-148Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The modelling of the behavior of a material exposed to fire is very complex and needs the coupling of fluid dynamics, combustion, heat and mass transfer, kinetics and so forth. A growing amount of studies and numerical models are reported in this field since the last decade. The aim of these models is to predict the fire behavior of wood, charring or non-charring polymers and even intumescent materials. However, these studies are seldom applied to formulated materials and especially flame retarded materials. In this study, an ethylene-vinyl acetate copolymer was formulated with a flame retardant (aluminum tri-hydroxide) and a synergist (nanoclays). A systematic approach for the characterization of the thermo-physical properties of the material as well as of its optical properties and the heat capacity of the decomposition gases is proposed and applied in this study. It is shown that it is possible to evaluate the input data required for pyrolysis modelling, even for multi decomposition steps materials. It is also shown that the diffusion of the gases inside the material had to be considered on the opposite of the classical assumption found in other studies. Indeed, using low mass diffusivity was the sole way to predict in the same time the temperature distribution and the mass loss rate of the material in a gasification experiments.

  • 89.
    Guay, Fanny
    et al.
    DBI Danish Institute of Fire and Security Technology, Denmark.
    Bouffier, Christian
    INERIS Institut National de l’Environnement Industriel et des Risques, France.
    Lange, David
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Mira da Silva, Miguel
    University of Lisbon, Portugal.
    Petersen, Laura
    EMSC European-Mediterranean Seismological Centre, France.
    Reitan, Nina Kristine
    RISE - Research Institutes of Sweden, Säkerhet och transport, Fire Research Norge.
    Storesund, Karolina
    RISE - Research Institutes of Sweden, Säkerhet och transport, Fire Research Norge.
    Theocharidou, Marianthi
    European Commission, Italy.
    Supporting disaster risk reduction through better critical infrastructure resilience2017Konferansepaper (Annet vitenskapelig)
  • 90.
    Guldåker, Nicklas
    et al.
    Lund University, Sweden.
    Eriksson, Kerstin
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Nieminen Kristofersson, Tuija
    Malmö University, Sweden.
    Preventing and Preparing for Disasters: The Role of a Swedish Local Emergent Citizen Group2015Inngår i: International Journal of Mass Emergencies and Disasters, ISSN 0280-7270, Vol. 33, nr 3, s. 360-387Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Disasters such as the storms that affected Sweden in 2005 and 2007 showed that citizens initially conducted a large part of the disaster response, such as clearing roads, giving psychosocial support to affected neighbours and repairing power lines in collaboration with power companies. As a result of these storms, an Emergent Citizen Group (ECG) was established in a village which continued to work on risk prevention, even after the event. The aim of this paper is to describe and analyse this local emergent citizen group’s continuing work on the prevention of local risk and vulnerability, and particularly, their work on flood prevention. The results indicate that authorities seldom understand the ECG’s concerns about risks. Authorities also lack the experience and capacity to collaborate with, and support, the ECG’s risk and vulnerability reduction work. Bureaucratic barriers and declining motivation among volunteers within the ECGs could undermine commitment to the prevention of risks.

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  • 91.
    Gustavsson, Börje
    et al.
    RISE - Research Institutes of Sweden, Samhällsbyggnad, Byggteknik.
    Williams Portal, Natalie
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Antonsson, Ulf
    RISE - Research Institutes of Sweden, Samhällsbyggnad, Byggteknik.
    Skydd av befintliga byggnadsfasader – en förstudie2019Rapport (Annet vitenskapelig)
    Abstract [en]

    Protection of existing building façades – preliminary study

    General concepts related to explosive loading and associated effects on buildings have been discussed. Requirements pertaining to the explosive and vehicle impact resistance of various building components were also elaborated along with the mention of relevant safety measures. Assessing the explosive resistance of existing buildings, with a focus on facades, was discussed in combination with design requirements and potential strength-ening approaches. Relevant literature covering the developments of this field was re-ferred to throughout the report.

    It was suggested that a future quality assurance method be devised with the title of "By-ggaS – Method for quality assurance of safe buildings". ByggaS is a method of working with safety issues related to the entire construction process. This encompasses quality assurance requirements (phased), planning and production. With the help of quality management routines and checklists, this method ensures that quality is met in each process through continuous documenting, communicating, checking and verifying the work. Overall, ByggaS allows for an increased quality and safety of the building to be delivered. It facilitates the work of individual construction projects and provides a more efficient process by offering the project participants a complete working method with associated tools/templates.

     

  • 92.
    Hallberg, Emil
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Safety.
    Sjöström, Johan
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Safety.
    Kahl, Fredrik
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Safety.
    Termisk påverkan från läckande gasolslangar2019Rapport (Annet vitenskapelig)
    Abstract [en]

    Thermal influence from leaking liquefied petroleum gas: The radiant heat flux from 3 leakage scenarios of liquefied petroleum gas (LPG) was studied to determine safety distances when refilling LPG tanks from tank trucks. The three scenarios were a larger and a smaller leakage from a pipe and leakage from a textile reinforced rubber hose. Steady state tests with 5 minutes of burn time were performed as well as tests with 1 minute of burn time after which the emergency stop was activated. Measurements with water cooled heat flux meters and plate thermometers were used to determine heat flux levels. Measurements were designed to determine distances to heat fluxes of 12.5, 15 and 40 kW/m². Heat fluxes were measured both parallel and perpendicular to the flames at the same height as the leakage and 1 meter above the leakage.

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  • 93.
    Heidari, Mohammad
    et al.
    Fire Testing Centre, France ; Imperial College London, UK.
    Robert, Fabienne
    Fire Testing Centre, France.
    Lange, David
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Rein, Guillermo
    Imperial College London, UK.
    Probabilistic Study of the Resistance of a Simply-Supported Reinforced Concrete Slab According to Eurocode Parametric Fire2019Inngår i: Fire technology, ISSN 0015-2684, E-ISSN 1572-8099, Vol. 55, nr 4, s. 1377-1404Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present the application of a simple probabilistic methodology to determine the reliability of a structural element exposed to fire when designed following Eurocode 1-1-2 (EC1). Eurocodes are being used extensively within the European Union in the design of many buildings and structures. Here, the methodology is applied to a simply-supported, reinforced concrete slab 180 mm thick, with a standard load bearing fire resistance of 90 min. The slab is subjected to a fire in an office compartment of 420 m2 floor area and 4 m height. Temperature time curves are produced using the EC1 parametric fire curve, which assumes uniform temperature and a uniform burning condition for the fire. Heat transfer calculations identify the plausible worst case scenarios in terms of maximum rebar temperature. We found that a ventilation-controlled fire with opening factor 0.02 m1/2 results in a maximum rebar temperature of 448°C after 102 min of fire exposure. Sensitivity analyses to the main parameters in the EC1 fire curves and in the EC1 heat transfer calculations are performed using a one-at-a-time (OAT) method. The failure probability is then calculated for a series of input parameters using the Monte Carlo method. The results show that this slab has a 0.3% probability of failure when the compartment is designed with all layers of safety in place (detection and sprinkler systems, safe access route, and fire fighting devices are available). Unavailability of sprinkler systems results in a 1% probability of failure. When both sprinkler system and detection are not available in the building, the probability of failure is 8%. This novel study conducts for the first time a probabilistic calculation using the EC1 parametric curve, helping engineers to identify the most critical design fires and the probabilistic resistance assumed in EC1. © 2018 The Author(s)

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  • 94.
    Hoffmann, Lars
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Immersion of 400 volt traction battery in fresh water and salt water2018Rapport (Annet vitenskapelig)
    Abstract [en]

    By means of these tests, where Li-ion batteries have been immersed in both fresh water as well as 3 % salt water, it was demonstrated that it is completely safe to be both in the water and in the direct proximity of a battery, in this case, with 400 volt direct current. This conclusion holds, on the condition that the exposed individual, in the direct proximity of the battery, does not actively touch any of the battery's poles. Analogous to this, it can be assumed that nor does an electric vehicle, which for some reason has entered a watercourse consisting of either fresh water or seawater, constitute a danger for those bathing in the immediate vicinity of the electric vehicle. However, this assumes that an individual who is diving or bathing does not touch exposed parts of the traction system (explanation, e.g. open battery case and directly taking hold of live exposed parts of the traction battery and its cells). However, these parts are normally built into the vehicle's protective structures and are hard to access by inadvertent contact. The commercially available, factory produced, electric vehicles made by serious designers and automotive companies have a monitoring system in their systems that immediately switch off the power supply from the traction battery to the electric vehicle's traction system. This provides additional personal protection for anyone (e.g. fireman) who has the task of helping passengers who have entered a watercourse along with their electric vehicle. During immersion in salt water, a pungent chlorine gas was generated, which can be thought to collect inside a vehicle's air pockets; whether these gas mixtures are flammable or not has not been studied during these tests. No drastic events could be observed during any of these tests, however, one should be aware that a battery, which for some reason has been in immersed in water and has not discharged, can still have a hazardous voltage level after many months. This is something that the rescue service, automotive mechanics and car recyclers in particular should be informed.

    Fulltekst (pdf)
    fulltext
  • 95.
    Honfi, Daniel
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Lange, David
    University of Queensland, Australia.
    Kozłowski, Marcin
    Lund University, Sweden ; Silesian University of Technology, Poland.
    Sjöström, Johan
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Lenk, Peter
    Arup, UK.
    Behavior of load-bearing glass at elevated temperature2018Inngår i: ce/papers, ISSN 2509-7075, Vol. 2, nr 5-6, s. 533-540Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    ABSTRACT The use of glass as a structural material has increased in the built environment over the last decades. Despite the large number of research projects and studies, it still poses difficulties in structural design. This particularly applies to the behaviour of glass in fire and under elevated temperatures since the available data on temperature dependent mechanical and thermal properties of glass is still limited. This contribution provides a brief overview of material properties of glass at elevated temperature and elaborates on current requirements for the fire safety included in standards.

  • 96.
    Honfi, Daniel
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Leander, John
    KTH Royal Institute of Technology, Sweden.
    Björnsson, Ívar
    Lund University, Sweden.
    Decision support for bridge condition assessment2017Inngår i: SMAR 2017 Proceedings, 2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The paper presents the first steps of the development of a theoretical framework for a rational yet practical decision making process concerning the condition assessment of existing bridges in Sweden. The main focus is on how to choose the appropriate level of enhanced conditions assessment considering aspects of model sophistication, uncertainty consideration and knowledge content utilisation. A conceptual case study is presented exemplifying how the framework can be used to structure the assessment actions of a steel bridge subjected to fatigue deterioration.

  • 97.
    Honfi, Daniel
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Lechner, Thomas
    NCC AB, Sweden.
    Köhler, Jochen
    NTNU, Norway.
    Rational maintenance of timber bridges2017Inngår i: Conference proceedings, ICTB 2017. 3rd International Conference on Timber Bridges / [ed] Gustafsson, Anders; Pousette, Anna; Hagman, Olle; Ekevad, Mats, 2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The present paper provides some ideas about how decisions concerning maintenance of timber bridges should be made in a rational way. First, a brief discussion is provided concerning the evolution of maintenance strategies in general and it is suggested that maintenance of timber bridges should follow a risk-based approach. Then the discussion moves on to the condition assessment of timber bridges with a main focus on inspection and monitoring. The use of non-destructive testing methods and structural health monitoring is highlighted with regard to collecting useful information for maintenance decisions. It is argued that the information collected, should be used in a Bayesian decision analysis framework, which is especially useful in quantifying to value of information and thus the worth of various inspection and monitoring alternatives.

    Fulltekst (pdf)
    fulltext
  • 98.
    Honfi, Daniel
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Williams Portal, Natalie
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Leander, John
    KTH Royal Institute of Technology, Sweden.
    Larsson Ivanov, Oskar
    Lund University, Sweden.
    Björnsson, Ívar
    Lund University, Sweden.
    Plos, Mario
    Chalmers University of Technology, Sweden.
    Zandi, Kamyab
    Chalmers University of Technology, Sweden.
    Carneiro, Erica
    NCC AB, Sweden.
    Lechner, Thomas
    NCC AB, Sweden.
    Magnusson, Jonas
    NCC AB, Sweden.
    Gabrielsson, Henrik
    Tyréns AB, Sweden.
    Inspection and monitoring of bridges in Sweden2018Rapport (Annet vitenskapelig)
    Abstract [en]

    This report provides an overview about recent research activities and current practice concerning inspection and monitoring of the structural performance of bridges and the related decision-making process. A brief review of common methods of collecting information on structural performance of bridges is presented, followed by a description of the use of the information collected in structural analysis and maintenance planning. An overview about the state of the art is given including recent scientific developments. Finally, the current Swedish practice for bridge management is presented.

    Fulltekst (pdf)
    fulltext
  • 99.
    Huang, Chen
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    De Grahl, Johanna
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Nessvi, Ken
    Process Safety Group, Sweden.
    Lönnermark, Anders
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Persson, Henry
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Explosion characteristics of biomass dust: comparisonbetween experimental test results and literature data2019Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The design of explosion mitigation strategies e.g. vent design is mainly based on dust explosioncharacteristics such as the maximum explosion pressure XÇïÓ and the deflagration index n! of dustcloud, which are defined in various standards.The wood dust explosion characteristics can be directly obtained by performing standard tests, and testresults are also available in the literature. However, the parameters for one type of dust may varysubstantially in the literature. For example, the n! value for one wood dust is 11.4 times higher thananother wood dust in Gestis-Dust-Ex database. The reason for such large variation in explosionparameters is due to factors such as material properties, particle size distribution, particle shape, moisturecontent, turbulence level during tests and so on.The objectives of this paper are (i) to carry out dust explosion tests for XÇïÓ and n! for two wood dustswith well-described material parameters such as particle size distribution and moisture content accordingto European standards, (ii) to perform statistical analysis of wood dust explosion characteristics includingXÇïÓ and n! in the literature, (iii) to identify the effects of dust material parameters such as particle sizeand moisture contents on XÇïÓ and n! and (iv) to highlight the variation in XÇïÓ and n! and theimportance of obtaining knowledge about these properties of an individual dust, e.g. via dust explosiontests.

    Fulltekst (pdf)
    fulltext
  • 100.
    Huffmeier, Johannes
    et al.
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Bram, Staffan
    RISE - Research Institutes of Sweden, Säkerhet och transport, Safety.
    Human Impact on Safety of Shipping2018Rapport (Annet vitenskapelig)
    Abstract [en]

    Humans, especially the crews have an important role in the safe operation of ships. The crews, given the right circumstances are able to safely maneuver, navigate, maintain and operate the vessel. The crews are dependent on many factors that enable this work, from the design of the vessel and work place, the procedures, processes given by the ship management and the business approach the ship owner applies to the vessel.

    The traffic to and from Åland is an advanced transport system that enables safe ferry services in shipping fairways with narrow passages, meeting and crossing traffic as well as winter navigation - a shipping system combining people and technology to create safe transport.

    The introduction of more automation requires a systems perspective and will not be a straight forward development. Total autonomy as proposed by some technology developers is often neglecting the functions and roles that humans have on maritime safety and the business case for increased automation neglects the full contribution of humans onboard. Total autonomy will therefore require high-end products that are built on standardized complex systems. Controlling and monitoring these systems will set new requirements on operators to uphold situated understanding in these complex systems.

    Many aspects will be affected by increased automation towards smart shipping - regulations, organization, workplace, working methods, HMI, roles and skills. To cope with the foreseen changes it is important to develop further training, skills, experience, openness in the organization and familiarization giving the future crews the right pre-conditions to succeed in the future, as well as mindful design and integration of newly automated systems

    In the future, the ISM code will likely have to change to improve the interaction between land organisations and crews in order to facilitate better integration of split responsibilities and split physical locations by the management system which in the long run allows for an increased land-based monitoring and control

    of vessels’ systems and move certain tasks to shore to lower workload onboard, which should be one of the main drivers for automation.

    Fulltekst (pdf)
    fulltext
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