The Experts below are selected from a list of 13242 Experts worldwide ranked by ideXlab platform
Jose L. Torero - One of the best experts on this subject based on the ideXlab platform.
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Fire Safety Design for tall buildings
Procedia Engineering, 2014Co-Authors: Adam Cowlard, Adam Bittern, Cecilia Abecassis-empis, Jose L. ToreroAbstract:In any subject area related to the provision of Safety, failure is typically the most effective mechanism for evoking rapid reform and an introspective assessment of the accepted operating methods and standards within a professional body. In the realm of tall buildings the most notable failures in history, those of the WTC towers, widely accepted as Fire induced failures, have not to any significant extent affected the way they are Designed with respect to Fire Safety. This is clearly reflected in the surge in numbers of Tall Buildings being constructed since 2001. The combination of the magnitude and time-scale of the WTC investigation coupled with the absence of meaningful guidance resulting from it strongly hints at the outdatedness of current Fire engineering practice as a discipline in the context of such advanced infrastructure. This is further reflected in the continual shift from prescriptive to performance based Design in many parts of the world demonstrating an ever growing acceptance that these buildings are beyond the realm of applicability of prescriptive guidance. In order for true performance based engineering to occur however, specific performance goals need to be established for these structures. This work seeks to highlight the critical elements of a Fire Safety strategy for tall buildings and thus attempt to highlight some specific global performance objectives. A survey of tall building Fire investigations is conducted in order to assess the effectiveness of current Designs in meeting these objectives, and the current state-of-the-art of Fire Safety Design guidance for tall structures is also analysed on these terms. The correct definition of the Design Fire for open plan compartments is identified as the critical knowledge gap that must be addressed in order to achieve tall building performance objectives and to provide truly innovative, robust Fire Safety for these unique structures.
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A risk based framework for performance based Fire Safety Design of steel and composite structures
2007Co-Authors: David Lange, Asif Usmani, Jose L. ToreroAbstract:For the development of performance based Design on a proper scientific basis the use of the concepts of risk and reliability is inevitable. The application of the concept of performance based Design is not simple because of the large ranges of probability and consequences of events which exist. While this concept poses major challenges, it also offers enormous opportunities because of the inherent element of choice. Traditional performance based Design methodologies approach the Design of structures for accidental loading linearly. Experience, however, suggests that the risk posed by Fire is not quantifiable without direct reference to the actual structure. Whilst this can be achieved to some degree of satisfaction in an ad-hoc manner, a systematic deterministic approach is proposed here for Fire Safety Design, as an alternative to linear methodologies or less robust ad-hoc treatments. A Design is separated into regions, non-exclusive of one another, which are classified according to a 'risk level' based upon the type of structure and the surrounding regions. Fires of concern are identified, and the probability of occurrence of each of these Fires is calculated along with the consequences to the structure. Using a 'risk matrix', regions of higher risk are identified and re-iterated to reduce the risk to an acceptable level.
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Applications of Computer Modelling to Fire Safety Design
2004Co-Authors: Jose L. Torero, Thomas SteinhausAbstract:Tools in support of Fire Safety engineering Design have proliferated in the last few years due to the increased performance of computers. These tools are currently being used in a generalized manner in areas such as egress, Fire modelling, smoke migration and evacuation and structural Design. Although these tools have been developed by highly competent individuals most users do not have similar credentials. The complexity of these tools requires more than the novice for their proper use and for many they should be deemed only as "Research Tools" and not as "Design Tools". The main questions to be asked are: • What are the limitations of the tools? • To what variables are they sensitive? • What skills are necessary to properly use them? • What level of accuracy do they produce? • How much better are the outputs of these tools than classical hand calculations? All these issues will be addressed through an example of the application of CFD tools to Fire resistance.
Takeyoshi Tanaka - One of the best experts on this subject based on the ideXlab platform.
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Integration of Fire Risk Concept into Performance-Based Evacuation Safety Design of Buildings
Fire Safety Science, 2011Co-Authors: Takeyoshi TanakaAbstract:The integration of the Fire risk concept in performance-based Fire Safety Design of buildings is beneficial in many aspects of Fire Safety. In this paper, a Risk-Based Evacuation Safety Design Method is proposed for rational evacuation Safety Design as an important area of Fire Safety Design. While the goal of this method is to control the evacuation risk in Fire within an acceptable level, the evacuation Safety verification in this method can be conducted according to the deterministic procedure in usual performance-based Fire Safety Design. The particular advantage of this method is that Design Fires and scenarios in the performance-based Design of a building are identified in a systematic manner. The practicability of this method in performance-based Designs of actual buildings is demonstrated by case studies for realistic buildings.
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Selection of Design Fires in Evacuation Safety Designs of Buildings Based on Fire Risk Concept
Bulletin of Japan Association for Fire Science and Engineering, 2008Co-Authors: Jun-ichi Yamaguchi, Ayako Ito, Takeyoshi TanakaAbstract:It is necessary for sound development of performance-based Fire Safety Design method of building to incorporate Fire risk aspect into the method. Design Fire scenarios and acceptable Safety criteria in P-B Fire Safety Design play the role to control Fire risk of buildings within an acceptable level. However, the relationship between the Fire risk and the Design Fires in current P-B Fire Safety Design method has not been clarified. In this paper, an attempt was made to develop a methodology for appropriately selecting Design Fire for evacuation Safety Designs. Determination of acceptable Safety criteria and selection of growth rate coefficient of heat release rate of Design Fire in evacuation Safety Designs are considered.
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risk based selection of Design Fires to ensure an acceptable level of evacuation Safety
Fire Safety Science, 2008Co-Authors: Takeyoshi TanakaAbstract:In a performance-based (P-B) Fire Safety Design, the level of Fire Safety of a building achieved by the Design depends upon the Design Fire scenarios and acceptable Safety criteria used. In other words, their essential role is to keep the Fire risk of a building below an acceptable level. However, the relationship of the Design Fire with the acceptable Fire risk is not clearly recognized, which often causes Fire performance gaps between a P-B Fire Safety Design and the existing building Fire code. It is thought to be vital for a P-B Fire Safety Design method to incorporate Fire risk concepts for its sound development. In this paper, consideration for determining acceptable Fire risk in the context of Fire Safety Design is made and a methodology for selecting such a Design Fire as to ensure the risk of evacuation in Fire be under the acceptable level is proposed.
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a pilot case study of a performance based Fire Safety Design method to a multi tenant office building
Fire Science and Technology, 1998Co-Authors: Kawori Koya, Yoshifumi Ohmiya, Kazunori Harada, Takeyoshi Tanaka, Akihiko Hokugo, Ichiro HagiwaraAbstract:A pilot case study was carried out to examine the feasibility of a performance based Fire Safety Design system to be developed in Japan. This system intends to give more degree of freedom in Fire Safety Design than the method prescribed in current building standards law of Japan. In place of prescriptive solutions, a hierarchy of objectives/ functional requirements/ performance requirements was defined by a pair of Design Fire condition (input) and acceptable conditions (output). The critical values were selected so that the current prescriptive requirement would satisfy the criteria without too much redundancy. In this way, the system can derive many alternative Design solutions without changing the absolute level of Safety. As a first pilot case study, the system was applied to an four-storied multi-tenant office buildings. The study was carried out for control of Fire spread and life Safety verification.
Jonatan Gehandler - One of the best experts on this subject based on the ideXlab platform.
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Fire Safety Design of road tunnels
2020Co-Authors: Jonatan GehandlerAbstract:This thesis can be described as a journey in performance-based Fire Safety Design. Along the way questions such as what Fire Safety is, how it can be measured, whether we are posing the right questions, or engineer the best solutions, have arisen. The Safety journey naturally started out with the traditional view, with Fire Safety engineering based on limit-based Design. Using this paradigm the Safety problem is limited to Fire Safety issues, and Safety levels are defined for each Fire Safety objective in isolation. This contradicts the basic rationale of decision-making where the best trade-off is sought between all objectives, most often by use of Cost-Benefit Analysis (CBA). This naturally led to the second stop of the Safety journey called CBA-based Design where risk is exchanged as a cost factor in a cost-benefit framework. In this paradigm Safety is a relative concept depending also on a few other measurable objectives. Throughout this work, the focus of the journey has been on road tunnels. Tunnels are hard physical and technical systems. However, they exist in a social reality and a complex society. During the Design process many social and soft issues surface that can conflict with technical Fire Safety measures. The journey thus went on to acknowledge both the scientific or technical aspects of risk and social structures; the ethical and democratic aspects of risk, in a decision-making framework. This emphasizes how the problem is framed, what our objectives are, and how creative alternatives are generated and assessed. It may not even be relevant to talk about "how safe should the tunnel be" because it is subordinate to the overall decision condition, all aspects considered. In the end a Design alternative is chosen that exhibit the highest utility on all objectives together, i.e. Safety in balance with other objectives. For any tentative Design, Safety can develop in two directions; Firstly, it may be that some Safety measures are too conservative or in conflict with other objectives such as cost or the environment, i.e. resources are better used elsewhere. Secondly, it may also be possible to achieve more Safety; it is argued that a Vision Zero Design philosophy with its emphasis on inherently safer or fail-safe systems highlight important Safety qualities which are not highlighted in limit-based or CBA-based Design. Along the way (a) road tunnel Fire Safety and risk literature were studied, (b) interviews were made with tunnel Fire Safety professionals (c) performance based requirements for road tunnel Fire Safety were derived, (d) the accuracy of tunnel Fire dynamics models applied in road tunnel Fire risk analysis was compared with experimental data, and (e) the Design framework of Fire Safety engineering was critically analyzed and an alternative Fire Safety Design framework was proposed. (Less)
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The theoretical framework of Fire Safety Design: Reflections and alternatives
Fire Safety Journal, 2017Co-Authors: Jonatan GehandlerAbstract: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.
Johan Lundin - One of the best experts on this subject based on the ideXlab platform.
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On quantification of error and uncertainty in two-zone models used in Fire Safety Design
Journal of Fire Sciences, 2005Co-Authors: Johan LundinAbstract:The error in smoke transport models have mainly been analyzed with qualitative approaches till date. The results make it difficult to perform a quantitative assessment of the model error in Fire Safety Design applications. Even if a model has a substantial model error, it can be a very useful tool, as long as the Designer is aware of the errors and the uncertainties in the predictions. This paper presents a methodology to quantify the error in model predictions and the associated uncertainties with a statistical analysis of multiple scenarios. The knowledge of the model error can then be used to adjust future model predictions in order to take the error into account explicitly. This is done with an adjustment model valid for predictions during the whole pre-flashover phase of the Fire scenario and not just at a single point in time. The approach taken is based on a quantitative comparison of model predictions and experimental measurements from several Fire scenarios which constitute a scenario configuration. The application of the method is presented in a subsequent paper, where the model error in temperature predictions by the two-zone model CFAST 2.0 is analyzed.
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Fire Safety Design Based on Risk Assessment
Fire Science and Technology, 2000Co-Authors: Robert Jönsson, Johan LundinAbstract:The present paper concerns a performance-based Fire Safety analysis and Design of a high-rise building. The resulting Fire Safety recommendations are compared with those specified by acceptable solutions in terms of the earlier prescriptive building code. The respective risk to life resulting from the analysis is compared and discussed. The benefit and need of using a risk based verification method as a complement to a deterministic Fire Safety engineering method is demonstrated. The cost-effectiveness of different solutions is also demonstrated. This paper is based on the results from a case-study presented at the 2nd International Conference on Performance-Based Codes and Fire Safety Design Methods in Maui 1998.
Meng Ming-zha - One of the best experts on this subject based on the ideXlab platform.
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Performance-based Fire Safety Design for a shopping mall based on quasi-Safety area
Fire Science and Technology, 2014Co-Authors: Meng Ming-zhaAbstract:A novel Fire Safety approach that promoted the Fire Safety Design of a shopping mall was presented based on quasiSafety area conception.Several solutions were employed to strengthen Fire Safety,such as reasonable Fire Safety districts, real Fire parameters,evacuation simulations,Fire separations with toughened glass and water injector.The evaluation and experiment data proved that the quasi-Safety area and independent Fire Safety area were effective policy in shopping mall Fire Safety Design which could be referenced in future Fire Safety Design.