The use of a mathematical multicriteria decision-making model for selecting the fire origin room
R. Machado Tavares 1, J.M. Lopes Tavares 2 and S.L. Parry-Jones 3
1 Fire Safety Engineering Group, University of Greenwich, 30 Park Row, Greenwich, London SE10 9SL, UK ; 2 FBV-Faculdade Boa Viagem, Rua Professor Eduardo Wanderley Filho, 539-Boa Viagem-Recife/PE, 51020-170, Brazil ; 3 Windspeed Limited (trading as Vector Instruments), 115 Marsh Road, RHYL, North Wales, LL18 2AB, UK
Abstract
Over the last three decades, the fire safety codes have been changing from a prescriptive approach to a performance-based one. Some countries, such as the USA, Sweden, New Zealand, Australia and the UK, are in an advanced stage of development and implementation of the performance-based codes. However, there are some difficulties in this process. Most of them are due to the uncertainties associated with fire design. For instance, one of the questions that need to be answered is how to select the most probable fire origin room (FOR)? On the other hand, to know where the FOR is located is also an important aspect in terms of forensic issues. Given that, to address this question is an important step for the establishment of fire designs (i.e., pre-fire phases) and also for fire investigations (i.e., post-fire phases). This paper proposes a methodology for selecting the FOR through the use of a mathematical multicriteria decision-making model: the analytical hierarchy process (AHP). The proposed method is then applied to a hypothetical study case. The results are presented and discussed in this paper.
The Use of Numerical Optimisation Techniques in Computational Fire Engineering Modelling based on an Evacuation Analysis Problem
Authors:Rodrigo Machado Tavares; João Marcelo Lopes Tavares
Source: ENGOPT 2008 - International Conference on Engineering Optimization, 2008, Rio de Janeiro. , Rio de Janeiro, Brasil (2008)
ISBN:978-85-7650-152-7
URL:http://www.engopt.org/nukleo/pdfs/0060_full_paper_rodrigo_engopt.pdf
Keywords:Evacuation Time; Numerical Optimisation Techniques; Design of Experiments; Response Surface Model; Evacuation Simulation Tool
Abstract:
A common problem faced by fire safety engineers in the field of evacuation analysis is the optimal positioning of exits within arbitrarily complex structures. This problem is usually addressed through time consuming and expensive trial-error analysis. While a solution is usually found to this problem, it is seldom optimal or even near optimal, resulting in a compromise in building performance and safety. For instance, there is no clear guidance regarding: where to place an exit in order to produce minimum evacuation times? Is it better to have two exits of X m width or one exit of 2X m width? If two exits are required, what is the optimal relative positioning of these exits? The analysis required to address these questions grows in difficulty as the available options and hence complexity of the scenario increases. While attempting to address this issue while dealing with only two exits may be manageable, what if there were 10 exits, each of varying dimensions? How would engineers know they had found the optimal or near optimal solution? In the other hand, numerical optimisation techniques have been applied in a range of different fields such as structural analysis and have been shown to be a powerful approach for designers, saving time and costs in the pursuit of optimal solutions. Therefore, this work intends to demonstrate how these techniques can be applied to evacuation analysis to determine optimal configurational layout. Particularly, we present a methodology that combines the use of numerical optimisation techniques (and associated concepts such as: Design of Experiments and Response Surface Models) with an evacuation simulation tool. The proposed methodology is demonstrated through an example involving a squared room with one and two exits. The methodology is applied to this problem and the optimal exit configuration is determined.