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1 – 10 of over 9000Amit Chandra, Anjan Bhowmick and Ashutosh Bagchi
The study investigates the performance of a three-story unprotected steel moment-resisting frame (SMRF) designed for high seismic demand in the fire-only (FO) and post-earthquake…
Abstract
Purpose
The study investigates the performance of a three-story unprotected steel moment-resisting frame (SMRF) designed for high seismic demand in the fire-only (FO) and post-earthquake uniform and traveling fires (PEF). The primary objective is to investigate the effects of seismic residual deformation on the structure's performance in horizontally traveling fires. The traveling fire methodology, unlike conventional fire models, considers a spatially varying temperature environment.
Design/methodology/approach
Multi-step finite element simulations were carried out on undamaged and damaged frames to provide insight into the effects of the earthquake-initiated fires on the local and global behavior of SMRF. The earthquake simulations were conducted using nonlinear time history analysis, whereas the structure in the fire was investigated by sequential thermal-structural analysis procedure in ABAQUS. The frame was subjected to a suite of seven ground motions. In total, four horizontal traveling fire sizes were considered along with the Eurocode (EC) parametric fire for a comparison. The deformation history, axial force and moment variation in the critical beams and columns of affected compartments in the fire heating and cooling regimes were examined. The global structural performance in terms of inter-story drifts in FO and PEF scenarios was investigated.
Findings
It was observed that the larger traveling fires (25 and 48%) are more detrimental to the case study frame than the uniform EC parametric fire. Besides, no appreciable difference was observed in time and modes of failure of the structure in FO and PEF scenarios within the study's parameters.
Originality/value
The present study considers improved traveling fire methodology as an alternate design fire for the first time for the PEF performance of SMRF. The analysis results add to the much needed database on structures' performance in a wide range of fire scenarios.
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Ali Nadjai, Naveed Alam, Marion Charlier, Olivier Vassart, Xu Dai, Jean-Marc Franssen and Johan Sjostrom
In the frame of the European RFCS TRAFIR project, three large compartment fire tests involving steel structure were conducted by Ulster University, aiming at understanding in…
Abstract
Purpose
In the frame of the European RFCS TRAFIR project, three large compartment fire tests involving steel structure were conducted by Ulster University, aiming at understanding in which conditions a travelling fire develops, as well as how it behaves and impacts the surrounding structure.
Design/methodology/approach
During the experimental programme, the path and geometry of the travelling fire was studied and temperatures, heat fluxes and spread rates were measured. Influence of the travelling fire on the structural elements was also monitored during the travelling fire tests.
Findings
This paper provides details related to the influence of travelling fires on a central structural steel column.
Originality/value
The experimental data are presented in terms of the gas temperatures recorded in the test compartment near the column, as well as the temperatures recorded in the steel column at different levels. Because of the large data, only fire test one results are discussed in this paper.
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Marion Charlier, Antoine Glorieux, Xu Dai, Naveed Alam, Stephen Welch, Johan Anderson, Olivier Vassart and Ali Nadjai
The purpose of this paper is to propose a simplified representation of the fire load in computational fluid dynamics (CFD) to represent the effect of large-scale travelling fire…
Abstract
Purpose
The purpose of this paper is to propose a simplified representation of the fire load in computational fluid dynamics (CFD) to represent the effect of large-scale travelling fire and to highlight the relevance of such an approach whilst coupling the CFD results with finite element method (FEM) to evaluate related steel temperatures, comparing the numerical outcomes with experimental measurements.
Design/methodology/approach
This paper presents the setup of the CFD simulations (FDS software), its corresponding assumptions and the calibration via two natural fire tests whilst focusing on gas temperatures and on steel temperatures measured on a central column. For the latter, two methods are presented: one based on EN 1993-1-2 and another linking CFD and FEM (SAFIR® software).
Findings
This paper suggests that such an approach can allow for an acceptable representation of the travelling fire both in terms of fire spread and steel temperatures. The inevitable limitations inherent to the simplifications made during the CFD simulations are also discussed. Regarding steel temperatures, the two methods lead to quite similar results, but with the ones obtained via CFD–FEM coupling are closer to those measured.
Originality/value
This work has revealed that the proposed simplified representation of the fire load appears to be appropriate to evaluate the temperature of steel structural elements within reasonable limits on computational time, making it potentially desirable for practical applications. This paper also presents the first comparisons of FDS–SAFIR® coupling with experimental results, highlighting promising outcomes.
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Khadejah Alameen Abouleiwun, Hazem M.F. Elbakry, Muhammad Ahmed Diab and S.F. El-Fitiany
In this study, the behavior of a multi-story flat plate structure during fire exposure is investigated using numerical simulations conducted with using ABAQUS software.
Abstract
Purpose
In this study, the behavior of a multi-story flat plate structure during fire exposure is investigated using numerical simulations conducted with using ABAQUS software.
Design/methodology/approach
A three-dimensional finite element model is then carried out on the RC flat slab structure exposed to standard ISO-834 fire at different location arrangements. The model examines mid-span deflection, shear demand on the columns, bending moment and the membrane action of the floor slab.
Findings
The latter plays a main role to increase the capability and ductility of the slab at longer fire exposure to compensate the reduction in the flexural capacity. Also, shear demand in columns becomes bigger in cases of more than one surrounding slab exposed to fire at the same time.
Originality/value
This work focuses on the influence of the horizontal force on columns due to thermal expansion of slab which should be taken into account in the design of multistory multi-bay building considering it the same as the resulted horizontal force from the wind and seismic effect, the traveling fire and the restraint effect.
Mhd Anwar Orabi, Jin Qiu, Liming Jiang and Asif Usmani
Reinforced concrete slabs in fire have been heavily studied over the last three decades. However, most experimental and numerical work focuses on long-duration uniform exposure to…
Abstract
Purpose
Reinforced concrete slabs in fire have been heavily studied over the last three decades. However, most experimental and numerical work focuses on long-duration uniform exposure to standard fire. Considerably less effort has been put into investigating the response to localised fires that result in planarly non-uniform temperature distribution in the exposed elements.
Design/methodology/approach
In this paper, the OpenSees for Fire framework for modelling slabs under non-uniform fire exposure is presented, verified against numerical predictions by Abaqus and then validated against experimental tests. The thermal wrapper developed within OpenSees for Fire is then utilised to apply localised fire exposure to the validated slab models using the parameters of an experimentally observed localised fire. The effect of the smoke layer is also considered in this model and shown to significantly contribute to the thermal and thus thermo-mechanical response of slabs. Finally, the effect of localised fire heat release rate (HRR) and boundary conditions are studied.
Findings
The analysis showed that boundary conditions are very important for the response of slabs subject to localised fire, and expansive strains may be accommodated as deflections without severely damaging the slab by considering the lateral restraint.
Originality/value
This work demonstrates the capabilities of OpenSees for Fire in modelling structural behaviours subjected to non-uniform fire conditions and investigates the damage pattens of flat slabs exposed to localised fires. It is an advancing step towards understanding structural responses to realistic fires.
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The purpose of this paper is to investigate approaches pertaining to qualitative fire risk assessment of existing hotel facilities, for the purpose of identifying and eliminating…
Abstract
Purpose
The purpose of this paper is to investigate approaches pertaining to qualitative fire risk assessment of existing hotel facilities, for the purpose of identifying and eliminating fire hazards, and meeting requirements of the current legislation.
Design/methodology/approach
The paper carries out several research activities, including: identifying the set of factors that render hotel facilities a high‐risk type of facilities in fires; investigating potential high‐risk areas to fires in hotels; exploring the role of hotel managers towards operating safe hotel facilities; discussing the concept of fire risk management, and the role of fire safety inspections as a risk mitigation strategy to ensure the adherence of existing hotels to fire safety legislation; and describing a methodical approach that fire safety inspectors can follow while conducting fire safety inspections. The paper also presents the development of a qualitative fire risk assessment tool, whereby existing hotel facilities can be assessed.
Findings
The paper establishes that hotel facilities are a high‐risk type of facilities in fire emergencies due to the combination of several risk factors. The fire risk assessment tool provides 76 items to assess, in seven main divisions, including exits, fire protection systems, electrical, fire doors, hazardous materials, housekeeping and miscellaneous.
Originality/value
This paper provides for a better comprehension of the roles of hotel managers towards operating safe hotel facilities. The paper emphasizes adherence of existing hotels to fire safety legislation to ensure the minimum level of safety for guests in all hotel properties. It serves to enhance the understanding of the potential dangers present in hotel facilities. It is of practical value to hoteliers responsible for the day‐to‐day operation of hotel facilities and for surveyors inspecting such properties.
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Thomas Ronan and Richard Teeuw
– The purpose of this paper is to explore fire risk and preparedness, with regard to water flow rates and building types in London, focusing on Southall district.
Abstract
Purpose
The purpose of this paper is to explore fire risk and preparedness, with regard to water flow rates and building types in London, focusing on Southall district.
Design/methodology/approach
A land use survey was carried out to identify water requirements for firefighting across the study area. Local fire hydrant flow rates were analysed, using measurements taken during 2013 and archive data held by the London Fire Brigade (LFB). QGIS was used to explore relationships between fire hydrant flow rates, urban fire risk and socio-economic vulnerability data held by the LFB.
Findings
A new type of map, which includes data on water flow rates and building types, was created using QGIS and applied to Southall district, resulting in a map showing Combined Vulnerability to fires. Inadequate fire hydrant water supply was found across many parts of the borough.
Practical implications
This new approach to the evaluation and mapping of urban fire risk could be applied in other cities, to assess problems with water supply and the firefighting water flow requirements of various building types. The methodology can thus assist with adaptations to urban fire resource allocation, tactics, planning and preparedness.
Social implications
When socio-economic data are also available, this Geographical Information System-based methodology becomes very useful for assessing fire risk and developing strategies for preparedness and response.
Originality/value
This is the first time that London’s fire hydrant water pressures have been mapped and linked with socio-economic vulnerability maps, to produce a Combined Vulnerability map for assessing fire risk.
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Anas M.M. Awad, Ketut Wikantika, Haytham Ali, Sohaib K.M. Abujayyab and Javad Hashempour
The rapid development of urban areas in Sleman District, Indonesia, has created new challenges for firefighting response services. One of the primary challenges is to identify the…
Abstract
Purpose
The rapid development of urban areas in Sleman District, Indonesia, has created new challenges for firefighting response services. One of the primary challenges is to identify the optimal locations for new fire stations, to improve service quality and maximize service coverage within the specified time.
Design/methodology/approach
This paper proposes a method for precisely calculating travel time that integrates delay time caused by traffic lights, intersections and congestion. The study highlights the importance of precise calculation of travel time in order to provide a more accurate understanding of the service area covered by the fire stations. The proposed method utilizes network analysis in ArcGIS, the analytical hierarchy process (AHP) and simple additive weighting (SAW) to accurately calculate travel time and to identify the best locations for new fire stations. The identification of new site was based on service safety, service quality, service costs and demographic factors and applied to the Sleman district in Indonesia.
Findings
The results showed that the total area covered by old and new fire stations decreased from 61% to 31.8% of the study area when the adjusted default speed scenario was implemented.
Practical implications
The results indicated that the default speed scenario could provide misleading information about the service area, while the adjusted default speed scenario improved service quality and maximized service coverage.
Originality/value
The proposed method provides decision-makers with an effective tool to make informed decisions on optimal locations for new fire stations and thus enhance emergency response and public safety.
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Chandrakantan Subramaniam, Hassan Ali and Faridahwati Mohd Shamsudin
The purpose of this paper is to identify the initial emergency response time of fire fighting teams in Malaysia.
Abstract
Purpose
The purpose of this paper is to identify the initial emergency response time of fire fighting teams in Malaysia.
Design/methodology/approach
In an emergency incident time is of the essence, and the basic philosophy of an emergency response agency is to respond as quickly as possible to minimize the loss of life and property damage. In the current study, emergency response performance refers to team members' speed in responding to emergency situations, which was measured as the time taken for the team members to get to the fire truck from the waiting room in selected fire stations in Malaysia. The data collection period lasted for five months.
Findings
This study found that the overall average initial emergency response time was 84 seconds, while the overall average weighted initial emergency response time was 3.71 seconds per meter. The current study has demonstrated that the average initial emergency response performed by fire fighting teams in Malaysia is apparently better than that reported by previous studies by other emergency responders.
Originality/value
This paper presents empirical evidence of the initial emergency response time of fire fighters in Malaysia, by taking into account the distance traveled by the responders. As such, the performance measure obtained gives a meaningful indicator. The finding of the current study is then compared to emergency response performance by other emergency response agencies in other countries.
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The proposed use of unlatched, reverse swing flappy doors is becoming widespread in the design of residential common corridor smoke control systems. This article explores the…
Abstract
Purpose
The proposed use of unlatched, reverse swing flappy doors is becoming widespread in the design of residential common corridor smoke control systems. This article explores the conceptual arguments for and against the use of these systems.
Design/methodology/approach
This article relies on industry experience, with reference to relevant building design practices, standards and research literature, to categorise arguments. These are collated into four common areas of concern relating to compartmentation, reliability, depressurisation and modelling practices. A final comparison is made between different common corridor smoke control system types for these four areas.
Findings
The article highlights several concerns around the use of flappy door systems, including the enforced breaches in stair compartmentation, uncertainties around system reliability, the reliance on door closers as a single point of failure, the impact of day-to-day building use on the system performance and the false confidence that modelling assessments can provide in demonstrating adequacy. The article concludes in suggesting that alternative smoke control options be considered in place of flappy door systems.
Originality/value
Discussion on the use of flappy door smoke control systems has been ongoing within the fire engineering community for several years, but there is limited public literature available on the topic. By collating the common arguments relating to these systems into a single article, a better understanding of their benefits and pitfalls has been provided for consideration by building design and construction professionals.
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