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In the residential sector single stud LSF walls are commonly used as load bearing and non-load bearing walls. But in situations where higher acoustic insulation levels and load bearing capacities are required, double stud LSF walls are used. However, fire performance of double stud LSF walls has not been investigated adequately unlike in the case of single stud LSF walls. There is insufficient research data on the fire performance of double stud wall systems. Therefore, this research investigated the fire performance of double stud walls under standard fire conditions using full scale test panels (3 m × 3 m) made of 90 mm lipped channel studs. Three full-scale fire tests were conducted to investigate the fire performance of load bearing double stud LSF walls. The fire test results of double stud LSF walls were then compared with those of single stud LSF walls with varying stud depth. The results revealed the presence of a unique heat transfer mechanism, resulting in an enhanced fire performance for double stud walls. The discontinuous stud arrangement within the cavity of double stud LSF walls was identified as the main contributor for the delayed heat transfer mechanism. This paper presents the details of this research and its results. It has also shown that the Direct Strength Method (DSM) based fire design equations developed for single stud LSF walls can be used to predict the failure times of double stud LSF walls exposed to fire.

The performance of light timber frame wall and floor assemblies in fire depends on their composition. The assemblies' ability to form fire-separations between building compartments (separating function) can be assessed by full-scale fire testing or calculation methods. Calculations are the low cost and more flexible alternative. The component additive method is a commonly used calculation method for fire design of timber structures. The method considers the insulation ability of the material layers present in the assembly. The component additive method described in this article is developed to be flexible to implement different materials and products of different dimensions. However, the amount of different materials currently included in this method is rather limited and there is no generally accepted procedure to implement new materials. This paper presents a common agreement of the procedure to implement new materials which comprises of: (1) the design and execution of model-scale fire tests; (2) determination of the modified thermal properties needed for simulations; (3) thermal simulations of assemblies in fire conditions; (4) development of design equations and; (5) verification by one or more full-scale fire test(s). The abovementioned steps have been clearly presented in this paper and supported by examples.

A novel fire testing method, named the Heat-Transfer Rate Inducing System (H-TRIS), is presented and described in this paper. The method directly controls the thermal boundary conditions imposed on a test specimen by controlling a specified time-history of incident radiant heat flux at its exposed surface. Accounting for the absorptivity and thermal losses at the exposed surface of the test specimen, H-TRIS can be programmed to control the net heat flux at the exposed surface; thus controlling the in-depth time dependent temperature distributions within the test specimen. H-TRIS can be used for imposing a wide range of time-histories of incident radiant heat flux (e.g. constant, linear, stepped), or in-depth time dependent temperature distributions (i.e. specified thermal gradients). Notably, this enables simulation of thermal boundary conditions experienced by materials or structures exposed to any source of heat – during a conventional fire test (e.g. standard furnace test), a large-scale fire test, a real fire, or some other thermal boundary conditions calculated using a fire model (e.g. zone or computational fluid dynamics model). H-TRIS enables complementary experimental studies with excellent repeatability at comparatively low economic and temporal costs relative to traditional furnace test methods, thus permitting multiple repeat tests and statistical studies of response to heating. Application of H-TRIS within a research project studying heat-induced concrete spalling is briefly presented and discussed, to illustrate the significance and novelty of the new fire testing method.

The response of structural systems to fire loads is typically assessed through performing ‘standard’ fire tests on individual members under constant mechanical boundary conditions. Full scale tests showed different behavior compared to the standard tests, but remain impractical. A promising approach to predict the behavior of full scale tests through testing individual structural members is Hybrid Fire Testing technique, where a subset of the structural system (Physical Substructure PS), is physically tested, while the remaining structure (Numerical Substructure NS), is simultaneously numerically analyzed. During the test, the mechanical boundary conditions on the PS and NS are continuously updated, and the updates are enabled by the communication framework. The communication framework is a key element for a successful hybrid fire test and this paper will present the development of such communication in MATLAB. To validate the communication framework, first, a single degree of freedom linear system was analyzed, followed by a ten-story steel frame structure exposed to design fire. The analysis of the latter underlined the importance of considering the effect of the cold surrounding in assessing the fire behavior of structures under design fires. Sensitivity analysis showed the importance of several parameters (time step and substructures stiffness) in hybrid fire testing.

To save weight and resources lightweight tanks with complex geometries made of glass-fibre reinforced plastics (GFRP) are a promising innovation for the transportation of dangerous goods. To realise the use of polymer tanks for such applications, their fire safety must be guaranteed. This paper presents solutions to protect fibre-reinforced plastic tanks from fire. The fire resistance of six GFRP tanks with different fire protection systems was tested in an outdoor full-scale fire test facility according to the regulation stipulated in the ADR (European agreement concerning the national carriage of dangerous goods by road). All tanks feature a complex geometry and a holding capacity of 1100 litres. The fire protection systems are composed of specialised resins as well as two intumescent coatings. All systems had a protective impact. The best results were achieved by the epoxy based intumescent coating, which was able to prolong the time needed to reach 150 °C inside the tank by 20 min. The emergence of a temperature holding point inside the tank due to condensation effects was observed at temperatures around 100 °C.

This paper presents experimental and numerical investigations on the collapse behavior of a 12 m × 6 m steel portal frame exposed to fire. A real fire test is conducted with a 4 m × 6 m fire compartment at the corner of the frame. Extensive thermal and structural responses of the frame are measured and presented. The experimental results show that the fire compartment collapses after 20-min heating with a critical column temperature of 850 °C. It is found that the measured gas temperatures are higher than the ISO fire, but lower than the parametric fire specified in EN 1991-1-2, indicating the underestimation of the thermal exposure for standard fires and unrealistic estimation for parametric fires. For steel temperatures, the prediction from parametric fires is in a reasonable agreement with the measurements by predicting a similar maximum temperature at a delayed time. The prediction from standard fires significantly underestimated the steel temperatures by up to 300 °C. The significant non-uniform gas temperature distribution along the frame height shows a two-zone model with a temperature gap of 200 °C. The maximum temperature of the members beyond the fire compartment exceeds 500 °C due to the spread of hot smoke. A numerical model is established and validated against experimental results. A potential outward collapse mode of the frame is predicted. It is suggested that a more realistic description of fire scenarios is still needed for a performance-based structural fire design, based on a better consideration of ventilation conditions and thermal properties of boundary enclosure.

This study evaluates the efficacy of compressed air foam (CAF) in comparison to common fire extinguishing media. Newly developed mixed-material burning cribs were used as a normative fire load for extinguishing tests to accurately represent the significantly elevated utilization of synthetic materials in everyday life. A series of outdoor experiments was carried out to analyze the effectiveness of the fire extinguishing medium CAF using synthetical class-A foaming agents from two different manufacturers, and compared them to water and water-foam solution as a function of the extinguishing distance. In a second series, performed inside a fire room, the efficiency of CAF-usage in indoor fires was evaluated. Moreover, the results of the indoor test series provided information about the composition of smoke gases based on the kind of extinguishing tactic used to suppress the fire. The results showed that under the tested conditions CAF suppressed fire more effectively than both water and water with foaming agents. CAF was able to wet areas hardly accessible to other extinguishing media, and due to its various simultaneously occurring effects and its compact jet with high kinetic energy, it cooled down temperatures more efficiently than water or water-foam solution.

Bridge failures due to fires are more common than failures due to extreme weather or earthquakes. Yet, unlike wind and earthquake loading, fire does not receive the same level of attention. Major 21st Century fire incidents involving bridges are listed and discussed. Various methods by which fire could be considered in design are reviewed and discussed. Sources of fire test data, which include only one full scale fire test to-date, are provided. It is hoped that by considering these factors, codes, standards and engineering practice could be updated to include consideration of fire in routine bridge design.

The Thread-fixed One-side Bolt (TOB) is the bolt that can be installed from outside of a steel tube column, which is anchored by the threads on the bolt hole wall instead of the nuts. A series of tests were carried out to investigate the shear behavior of the lapped connection bolted by TOBs using both the steady state fire tests and the transient state fire tests. The two observed failure modes of TOB connected lapped connections were the bolt hole bearing failure (failure mode 1) and the bolt shank fracture (failure mode 2). The high temperature might cause the change of failure mode from failure mode 1 to failure mode 2. Lapped connections using Standard High Strength Bolt (SHSB) were also tested. The comparison results showed that the ultimate shear resistance of lapped connections using TOBs at different temperatures was about 90% of that using SHSBs with the same configuration at steady state fire test. Applicability of the design equations provided by Eurocode 3 was validated by the steady state fire test results. A Finite Element Model (FEM) was built and validated by the test results and the FEM was used to further study more derailed parameter studies including the influence of bolt strength, the bolt pretension force and the high temperature to the shear behavior of TOB connected lap connections.

Advanced polymer matrix composites are widely used in modern aircraft and as such have to withstand fire to comply with safety regulations. The thermal degradation of these lightweight materials is a complex process involving chemical reactions in the solid and gas phases, potentially leading to flaming combustion. Here, we numerically investigate the heat feedback from the ignition of outgassing at the surface of a structural polymer matrix composite exposed to a pilot flame. Our model couples the thermal, physical and chemical processes in the solid phase to compute the composite degradation, as well as the production and movements of pyrolysates. A counterflow diffusion flame is used to model the ignition of the combustible effluent close to the sample surface, where the hot jet of the pilot flame impinges. The predictive capabilities of the method are demonstrated considering a carbon/epoxy composite subjected to a small-scale fire test. As input data for our model, material properties have been measured for virgin and partially burned samples via Differential Scanning Calorimetry, Xenon Flash Analysis and Thermogravimetric Analysis. The model is able to predict the backface temperature and time-to-ignition of the composite sample exposed to a flame with a good degree of accuracy.

This paper presents the details and analysis of a fire test conducted on a stainless steel cellular beam, as well as the development of a finite element model to further study the behavior. Cellular beams are increasingly popular in the construction as they provide a structurally and materially efficient design solution as well as allowing the passage of services. Their behavior in fire can be challenging as the web-post typically reaches higher temperatures than equivalent webs in solid beams. Stainless steel is also increasingly popular for structural applications, mainly due to its excellent corrosion resistance, as well as its other attractive physical and mechanical attributes. The focus in this paper is on the behavior of stainless steel cellular beams, which combine the attractive qualities of stainless steel with the structural efficiency of beams with openings, in fire. A fire test has been conducted which is described and discussed. Then, a finite element analysis model is developed to analyze the thermo-mechanical behavior of unprotected stainless steel cellular beams. The model is validated using the experimental results and then employed to investigate the important parameters which influence the behavior. acceptedVersion

One of the largest unknowns in structural fire engineering design is the fire itself, particularly in large internal environments, where real fires have been observed to travel around the floor plate. Several methodologies have been proposed to characterise these fires, most of which rely on the separation of the fire exposure into two so-called fields - near and far – allowing simplifying assumptions to be made. These models are now being used in the structural fire design. However, there is a paucity of validation data for these models withonly a few tests reported in the literature. The Tisova Fire Test was conducted on the ground floor of a 4-storey concrete frame building, with concrete and composite deck floors. The fire compartment had a total area of ca. 230m2, a height of 4.21 – 4.28 m, and a uniform fuel bed across the floor at 40kg/m2. This paper presents temperatures, spread rate and the observed behaviour of the travelling fire, comparing the current design guidance with the low temperatures observed in the experiment. The paper also examines theexperimental issues and the planning of these experiments with a view to helping others plan for and execute large scale fire tests in the future.

Fire testing of large-scale structural prototypes is costly and requires highly specialized facilities. For this reason, most of the research on the structural response to fire loading relies on cheaper single-component experiments. However, such experiments do not reproduce the internal force redistribution in a realistic assembly, which plays a pivotal role in determining the failure mode of every component. Hybrid fire testing overcomes this limitation by harnessing fire experiments and numerical simulations in a closed feedback loop. Specifically, the boundary conditions of the tested specimen are updated on-the-fly to match those of a numerically simulated subassembly. In order to test gypsum-plasterboard-based wall assemblies under realistic loading scenarios, the Danish Institute of Fire and Security Technology has recently implemented hybrid fire testing. This paper describes the developed hybrid testing setup and the results of a demonstrative experimental campaign.

Structural fire testing has traditionally relied on the use of the standard fire resistance test (i.e. furnace test) for assuring regulatory compliance of structural elements and assemblies, and in many cases also for developing the scientific understanding of structural response to fire. Conceived in the early 1900s and fundamentally unchanged since then, the standard testing procedure is characterized by its high cost and low repeatability. A novel test method, the Heat-Transfer Rate Inducing System (H-TRIS), resulting from a mental shift associated with controlling the thermal exposure not by temperature (e.g. temperature measured by thermocouples) but rather by the time-history of incident heat flux, was conceived, developed, and validated within the scope of the work presented in this paper. H-TRIS allows for experimental studies to be carried out with high repeatability, imposing rationally quantifiable thermal exposure, all at low economic and temporal cost. This works aims at demonstrating that a rational, and practical, understanding of the fire performance of structural systems during real fires is unlikely to be achieved only by performing additional standard fire resistance tests. Hence, H-TRIS presents an opportunity to help promote an industry-wide move away from the contemporary pass/fail and costly furnace testing environment.

Investigating the structural response of reinforced concrete beam-column sub-assemblies at elevated temperatures is the purpose of this paper. This goal was achieved by conducting the ISO-834 standard fire test on two identical one-third scaled reinforced concrete beam-column subassemblage test specimens. The test specimens, which each consisted of one reinforced concrete cantilever beam anchored at the mid-height of a reinforced concrete column, were installed together in a full scale furnace and subjected to downward and upward service loads, respectively. The fire compartment fully engulfed the cantilever beams (except the beams’ top face and the loading points), the beam-column connections and the lower columns. The fire test terminated after 74 min as soon as the tensile longitudinal steel bars of the upward-loaded cantilever beam attained the predefined critical temperature 530 °C. The lower columns exhibited partial concrete spalling and typical diagonal cracks appeared at the beam-column connections. Based on the recorded internal temperature distributions at the joint cores it was found that the material strength loss in the fire had insignificant impact on the load bearing mechanism of the joints. On the other hand, the gradual decrease in rotation capacity of the beam ends during the fire course considerably influenced the load-deflection relationship. A detailed numerical work has been carried out to simulate the response of the test specimens and will be published elsewhere.

Multi-storey mass timber buildings constructed with cross laminated timber and glulam are being developed globally. Where engineered timber such as glulam is utilized, the column to beam connections need to be constructed with a fire resistance rating equal to that of the connecting members. The preferred glulam connectors are either a concealed steel plate with bolts and dowels; or a concealed proprietary screw-in sleeve type connector. The fire resistance of connectors for glulam members is an unresolved design issue, as there is no clear methodology to assess their capacity under fire, when the timber is exposed and not clad behind fire protective plasterboard. There is limited fire test data on concealed connectors under shear forces, which is the normal loading condition within a constructed building. Fire test data is also limited on full-size specimens. Correlations developed to date to calculate concealed connector fire resistance have only limited application. A methodology for the design of glulam beam to column connections has been developed based on an extensive literature review, examining the key issues for connection failure. It has been determined that char rate for the timber at the connection needs to be increased above the normally accepted design values, due to the influence of the steel connectors. Secondly, the reduction in timber strength behind the char layer needs to be accounted for, by including a greater depth of reduced strength and stiffness timber, such that the connection can effectively transfer the applied forces through the timber to the steel connector. The methodology detailed within this paper provides a simple approach to evaluate the timber cover to the concealed steel connector, where the timber strength and stiffness are effective.

In a compartment fire, Externally Venting Flames (EVF) may significantly increase the risk of fire spreading to adjacent floors or buildings, especially when combustible insulation materials are installed on the building facade. An increasing number of recent reports suggest that existing fire engineering design methodologies cannot describe with sufficient accuracy the characteristics of EVF under realistic fire load conditions. In this context, a series of fire safety engineering design correlations used to describe the main EVF thermal characteristics, namely EVF centreline temperature and EVF-induced heat flux on the exposed facade surface, are comparatively assessed. Towards this end, measurements obtained in a medium- and a large-scale compartment-facade fire test are employed; aiming to broaden the scope of the validation study, predictions of the investigated correlations are further compared to measurements obtained in 6 large-scale fire tests found in the literature. It is found that the correlation proposed in EN1991-1–2 (Eurocode 1) for the estimation of the EVF centreline temperature is under-predicting the measured values in large-scale fire tests. In addition, it is concluded that estimation of the local flame emissivity should take into account the specific fuel type used in each case.

This paper discusses fires in informal settlements (otherwise known as slums, ghettos, shantytowns, etc.), which are regularly ravaged by fire in South Africa. Initially an overview of the problem is presented, highlighting the factors that contribute to the frequent, large conflagrations that occur. Details have been based on research conducted in Cape Town, South Africa, although the research is applicable to settlements worldwide. Data from recent fires where up to 4500 people were left homeless is included, highlighting aspects regarding fire spread and fire dynamics. Thereafter, preliminary results from a pilot study are presented where full-scale burn tests have been carried out on informal settlement dwellings, or “shacks”. Results from (a) a smoldering fire test, (b) 25 kg/m2 wood fire load test and (c) a ‘representative’ shack fire test are presented. For flaming fires it is shown that flashover in these small dwellings can occur in as little as one minute (depending on the fuel source), which is consistent with observations from professional firefighters in the field. Photoelectric smoke detectors, ionization, and rate-of-rise heat detectors were included during fire tests, to evaluate their performance in such confined spaces, as these are currently being either used or being considered for use in settlements. Activation times are reported for the different tests conducted.

A large-scale fire test was conducted on a compartment constructed from cross laminated timber (CLT). The internal faces of the compartment were lined with non-combustible board, with the exception of one wall and the ceiling where the CLT was exposed directly to the fire inside the compartment. Extinction of the fire occurred without intervention. During the fire test, measurements were made of incident radiant heat flux, gas phase temperature, and in-depth temperature in the CLT. In addition, gas flow velocities and gas phase temperatures at the opening were measured, as well as incident heat fluxes at the facade due to flames and the plume leaving the opening. The fuel load was chosen to be sufficient to attain flashover, to achieve steady-state burning conditions of the exposed CLT, but to minimize the probability of uncertain behaviors induced by the specific characteristics of the CLT. Ventilation conditions were chosen to approximate maximum temperatures within a compartment. Wood cribs were used as fuel and, following decay of the cribs, self-extinction of the exposed CLT rapidly occurred. In parallel with the large-scale test, a small scale study focusing on CLT self-extinction was conducted. This study was used to establish: the range of incident heat fluxes for which self-extinction of the CLT can occur; the duration of exposure after which steady-state burning occurred; and the duration of exposure at which debonding of the CLT could occur. The large-scale test is described, and the results from both the small and large-scale tests are compared. It is found that self-extinction occurred in the large-scale compartment within the range of critical heat fluxes obtained from the small scale tests.

A series of fire experiments was conducted using a 1:12 scale model of a shallow urban road tunnel with roof openings to clarify the flow structure of smoke and fresh air during a fire with a longitudinal external wind blowing above the roof openings. The model tunnel consisted of two road tubes separated by a pillar-type median structure. Five fire test cases were conducted by changing the heat release rate as the experimental parameter. When the smoke produced by a fire in the tunnel tube was exhausted by natural ventilation through the roof openings of the tunnel tube, fresh air was sucked in from the roof openings of the opposite tunnel tube. The flow of exhausted smoke and sucked-in fresh air created a complex three-dimensional flow structure inside the tunnel tubes. Stratified smoke that had formed under the ceiling of the tunnel tube was disturbed by the flow of sucked-in fresh air and was diffused on the upstream side of the fire. Compared to the condition without a longitudinal external wind, when a longitudinal external wind blew over the tunnel with the pillar median structure, the smoke spreading distance on the upstream side was longer than that without the external wind due to the diffusion of smoke. On the other hand, the smoke spreading distance on the downstream side of the fire was shorter than that without the external wind due to the improved smoke extraction performance by the Venturi effect of the longitudinal external wind. Furthermore, the smoke spreading distance on the downstream side was nearly constant and independent of the heat release rate of the fire, within the scope of our experimental conditions.

Recently, Magnesium Oxide (MgO) board has been widely used in LSF wall systems because of its improved acoustic properties, impact resistance, structural strength and serviceability. However, their thermal properties and fire performance have not been fully investigated. Therefore, in this research study thermal properties of two different types of MgO boards available in Australia were measured and their fire performance was investigated using three full-scale fire tests of LSF walls lined with two types of MgO board. Although the tests were conducted on two different types of MgO boards with different configurations, the fire test results gave a fire resistance level (FRL) of 30 minutes, in which the failure was initiated by integrity of the board with either board cracking or board joint opening. This paper presents the details of the thermal property tests and the three full-scale fire tests, and their results. In addition, the effects of different MgO boards, joint configurations and compounds, noggings, screw fastening techniques and cavity insulation on the fire performance of LSF walls are also presented.

In the case of corrugated web beams, based on experimental results, it was noticed that temperature development along the height of the web has a distinct pattern compared to the flat web beams. The particularity consists of a temperature decrease in the web, in the vicinity of the flange-to-web junction, assigned to the heat transfer by conduction and radiation. On this assumption, starting from the simple relations given in the fire design codes an analytical model is developed considering the heat conduction from the web to the flanges and the radiation heat transfer between web and flanges. The paper presents the results of the proposed analytical method against the experimental results and the numerical simulation. Both analytical and numerical models are compared to the experimental results obtained from the isolated element fire test and the real building fire test. A parametric study on the influence of the geometric dimensions is performed regarding also the time interval for the temperature development. For short term fire exposure, the web exhibits non-uniform temperature along the web height, while for long term fire exposure the entire cross-section tends to a homogeneous temperature.

The study presented herein shows an experimental methodology aimed at analysing the effectiveness of intumescent coatings through detailed characterisation of their thermo-physical response for a range of heating conditions and applied initial dry film thickness (DFT). Steel plates coated with a commercial solvent-based thin intumescent coating were exposed to well-defined and highly-repeatable heating conditions in accordance with the H-TRIS test method. Experimental results emphasise that the swelling process and the resulting swelled thickness govern the thermo-physical response of intumescent coatings, thus their effectiveness. During swelling, the coated steel asymptotically tends to the temperature range 300–350 °C, regardless of the heating condition or DFT. Thermo-gravimetric analysis demonstrates that the coating undergoes the swelling reaction at this temperature range. Once the swelling process is completed, the steel temperature increases above 350 °C. The steel temperature acts as an indicator of the swelling process, as the reaction occurs near the steel-coating interface. The intumescent coating swells and insulates the steel substrate by displacing the already-swelled coating towards the direction of the heat source. Aiming at predicting the swelling of intumescent coatings, empirical correlations are derived: the swelling rate is governed by the heating conditions and the maximum swelled thickness is governed by the initial DFT.

Data centers use electrical cables to provide power and transmit data. The jacket and insulation materials of electrical cables are usually made with plastics and could be the major source of combustible materials in data centers. Therefore, understanding the fire and smoke hazard of electrical cables is important for reducing fire loss. For this purpose, we examined six electrical cables including power and data cables using the intermediate-scale parallel panel fire test (PPT), small-scale Fire Propagation Apparatus (FPA) test, and smoke corrosivity test. The PPT results showed that one cable examined in the PPT failed both the fire propagation and smoke generation criteria, and others passed. The FPA test measured the Fire Propagation Index and Smoke Damage Index using the ignition and fire propagation measurements, and the test results demonstrate the consistency with the PPT test results. Three electrical cables were examined for the smoke corrosivity, with two low smoke zero halogen (LSZH) cables showing lower smoke corrosivity and a cable with PVC insulation/jacket showing higher smoke corrosivity. This study shows that the LSZH cables examined herein have good fire and smoke corrosion properties. The fire/smoke corrosivity test methods provide a comprehensive approach to evaluate fire risk of electrical cables.

Full-scale external fire test of a 92 m³ steel silo carried out in 2018 was the first such attempt to determine the effect of the fire on a free-standing silo. So far, the research conducted in this area focused mainly on the risk of explosion and internal fire. During the test, the following measurements were undertaken: temperature of silo coat and its internal load, deformation, wind speed and coat strain under load in normal conditions. The silo was loaded with a substance (gravel) exerting significant stress on its structure. Appropriate pre-test of the thermal interaction of the steel coat and silo contents was conducted. Despite the temperature of the steel coat, the silo did not collapse − only deformations of the coat were observed. The next planned step in this ongoing investigation is numerical modelling of the external fire event in silos. The data gathered in this study will be used to validate a model of the failure mode.

In current fire probabilistic risk assessments (PRAs) for nuclear power plants in the United States, fires due to transient combustibles are one of the top contributors to calculated plant risk. This does not comport with industry experience on the severity of transient fires. A two-phase project was developed to improve the realism of modeling transient fires in PRAs. In the summer of 2018, a large fire testing program was executed to test 99 fuel packages representative of transient combustibles in nuclear power plants. This paper develops a method to weight the test results using operational experience in the form of a fire events database maintained by the Electric Power Research Institute. The weighted test results were used to create probabilistic distributions of heat release rate, total energy release, and zone of influence (maximum distance for causing target damage). Additionally, the weighted test results were used to develop a generic approach for modeling the time-dependent behavior of a transient fire.

Light gauge steel frame (LSF) floor-ceiling systems are increasingly used in buildings without a full understanding of their thermal and fire resistance performance. Hence a numerical study was undertaken on the thermal performance of LSF floor-ceiling systems with varying configurations under standard fire conditions. The configurations included Lipped Channel and rivet fastened Rectangular Hollow Flange Channel section joists, gypsum plasterboard lining, steel sheathing, structural plywood and rockwool fibre insulation. The measured elevated temperature thermal property data of the above floor system components were included in the 3D thermal finite element models and the results were compared with fire test results. A good comparison showed that the developed finite element models can be used to simulate the thermal behaviour of LSF floor-ceiling systems with varying configurations. A parametric study was then undertaken to extend the thermal performance data in terms of time-temperature profiles for LSF floor-ceiling systems. Finite element analyses showed that the new LSF floor-ceiling system with the addition of thin steel sheathing performed significantly better than conventional systems. The use of thin steel sheathing on both sides of plasterboard showed further improvements. The use of cavity insulation was shown to be detrimental and thus improved floor-ceiling configurations were proposed.