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The purpose of this paper is to investigate different types of fire on structural steel members with damaged fireproofing. Two types of fire scenarios are considered, ASTM E119 fire and Hydrocarbon fire. In industrial facilities such as oil refineries, certain units maybe subjected to hydrocarbon fire, and its effect might be different than standard fire. The purpose of this study is to compare both types of fire scenarios on steel beams with damaged fireproofing and determine the fire rating of the damaged beams under each fire scenario.

The study is performed using computational methods, thermal-stress finite element analysis that is validated with experimental results. The results of practical beam sizes and typical applied loads in such structures have been plotted and compared with steel beams with non-damaged fireproofing.

The results show significant difference in the beam fire resistance between the two fire scenarios and show the fire resistance for beam under each case. The study provides percentage reduction in fire resistance under each case for the most commonly used cases in practice under different load conditions.

Extensive literature search has been performed by the authors, and few studies were found relevant to the topic. The question this study answers comes up regularly in practice. There are no standards to codes that address this issue.

This research paper aims to investigate reinforced concrete (RC) walls' behaviour under fire and identify the thermal and mechanical factors that affect their performance.

A three-dimensional (3D) finite element (FE) model is developed to predict the response of RC walls under fire and is validated through experimental tests on RC wall specimens subjected to fire conditions. The numerical model incorporates temperature-dependent properties of the constituent materials. Moreover, the validated model was used in a parametric study to inspect the effect of the fire scenario, reinforcement concrete cover, reinforcement ratio and configuration, and wall thickness on the thermal and structural behaviour of the walls subjected to fire.

The developed 3D FE model successfully predicted the response of experimentally tested RC walls under fire conditions. Results showed that the fire resistance of the walls was highly compromised under hydrocarbon fire. In addition, the minimum wall thickness specified by EC2 may not be sufficient to achieve the desired fire resistance under considered fire scenarios.

There is limited research on the performance of RC walls exposed to fire scenarios. The study contributed to the current state-of-the-art research on the behaviour of RC walls of different concrete types exposed to fire loading, and it also identified the factors affecting the fire resistance of RC walls. This guides the consideration and optimisation of design parameters to improve RC walls performance in the event of a fire.

In this study, the insulation fire ratings of lightweight foamed concrete, autoclaved aerated concrete and lightweight aggregate concrete were investigated using finite element modelling.

Lightweight aggregate concrete containing various aggregate types, i.e. expanded slag, pumice, expanded clay and expanded shale were studied under standard fire and hydro–carbon fire situations using validated finite element models. Results were used to derive empirical equations for determining the insulation fire ratings of lightweight concrete wall panels.

It was observed that autoclaved aerated concrete and foamed lightweight concrete have better insulation fire ratings compared with lightweight aggregate concrete. Depending on the insulation fire rating requirement of 15%–30% of material saving could be achieved when lightweight aggregate concrete wall panels are replaced with the autoclaved aerated or foamed concrete wall panels. Lightweight aggregate concrete fire performance depends on the type of lightweight aggregate. Lightweight concrete with pumice aggregate showed better fire performance among the normal lightweight aggregate concretes. Material saving of 9%–14% could be obtained when pumice aggregate is used as the lightweight aggregate material. Hydrocarbon fire has shown aggressive effect during the first two hours of fire exposure; hence, wall panels with lesser thickness were adversely affected.

Finding of this study could be used to determine the optimum lightweight concrete wall type and the optimum thickness requirement of the wall panels for a required application.

Fire safety of a building is becoming a prominent consideration due to the recent fire accidents and the consequences in terms of loss of life and property damage. ISO 834 standard fire test regulation and simulation cannot be applied to assess the fire performance of 3D printed concrete (3DPC) walls as the real fire time-temperature curves could be more severe, compared to standard fire curve, in terms of the maximum temperature and the time to reach that maximum temperature. Therefore, this paper aims to describe an investigation on the fire performance of 3DPC composite wall panels subjected to different fire scenarios.

The fire performance of 3DPC wall was traced through developing an appropriate heat transfer numerical model. The validity of the developed numerical model was confirmed by comparing the time-temperature profiles with available fire test results of 3DPC walls. A detailed parametric study of 140 numerical models were, subsequently, conducted covering different 3DPC wall configurations (i.e. solid, cavity and rockwool infilled cavity), five varying densities and consideration of four fire curves (i.e. standard, hydrocarbon fire, rapid and prolong).

3DPC walls and Rockwool infilled cavity walls showed superior fire performance. Furthermore, the study indicates that the thermal responses of 3DPC walls exposed to rapid-fire is crucial compared to other fire scenarios.

To investigate the thermal behaviour, ABAQUS allows performing uncoupled and coupled thermal analysis. Coupled analysis is typically used to investigate combined mechanical-thermal behaviour. Since, considered 3DPC wall configurations are non-load bearing, uncouple heat transfer analysis was performed. Time-temperature variations can be obtained to study the thermal response of 3DPC walls.

At present, there is limited study to analyse the behaviour of 3DPC composite wall panels in real fire scenarios. Hence, this paper presents an investigation on the fire performance of 3DPC composite wall panels subjected to different fire scenarios. This research is the first attempt to extensively study the fire performance of non-load bearing 3DPC walls.

A one‐dimensional finite element model, associated with a computer code, has been developed to simulate the thermal response of a decomposing glass‐fibre reinforced composite exposed to a fire environment. The numerical model uses a first‐order Arrhenius equation and includes: transient heat conduction; gas mass flux and internal heat convection of decomposition gases; density loss and Arrhenius decomposition of active material into decomposition gases and residual char; and endothermicity of the decomposition process. An empirical formula, obtained from furnace tests, has been applied to the model as the incident heat flux boundary condition at the heated surface. Presents results for the standard thickness of polyester‐based GRP laminate, 10.9mm, for offshore structures. The predicted temperature profiles are in good agreement with experimental temperatures obtained from furnace tests. This model is able to simulate fire performance characteristics for a large range of typical offshore components with different constructions and materials. It will enable accurate predictions of the life‐time of offshore components in severe offshore hydrocarbon fires.

In the present article, the authors have conducted a review on some of the recent developments given in the literature pertaining to the passive protection of concrete structures using intumescent coatings. Here, the main thrust is placed on the spalling phenomenon of concrete elements when exposed to elevated temperatures and fires.

In this context, it has been long established that prolonged thermal insult on concrete members will lead to egress of water, both physically bound as well as those present as water of hydration within the concrete matrix, in the form of steam through microchannels and associated pathways of least resistance, often resulting in the flaking of the surface of the structure. The latter process can ultimately lead to the exposure of the ferrous-based reenforcement elements, for instance, to higher temperatures, thus inducing melting. This, in turn, can result in substantial loss of strength and load-bearing capacity of the structural element that is already undergoing disintegration of its base matrix owing to heat/fire. Even though spalling of concrete structures has long been recognized as a serious problem that can often lead to catastrophic failure of infrastructures, such as buildings, bridges and tunnels, the utility of intumescent coating as a mitigation strategy is relatively new and has not been explored to its fullest possible extent. Therefore, in the latter parts of the review, the authors have endeavored to discuss the different types of intumescent coatings, their modes of actions and, in particular, their wider applicability in terms of protecting concrete elements from detrimental effects of severe or explosive spalling.

Given that spalling of concrete components is still a very serious issue that can result in loss of lives and destruction of critical infrastructures, there is an urgent need to formulate better mitigating strategies, through novel means and methods. The use of the intumescent coating in this context appears to be a promising way forward but is one that seems to be little explored so far. Therefore, a more systematic investigation is highly warranted in this area, especially, as the authors envisage a greater activity in the building and commissioning of more infrastructures worldwide incommensurate with augmented economic activities during the post-COVID recovery period.

The authors have conducted a review on some of the recent developments given in the literature pertaining to the passive protection of concrete structures using intumescent coatings. The authors have also included the results from some recent tests carried out at the facilities using a newly commissioned state-of-the-art furnace.

Light-Gauge Steel Frame (LSF) structures are popular in building construction due to their lightweight, easy erecting and constructability characteristics. However, due to steel lipped channel sections negative fire performance, cavity insulation materials are utilized in the LSF configuration to enhance its fire performance. The applicability of lightweight concrete filling as cavity insulation in LSF and its effect on the fire performance of LSF are investigated under realistic design fire exposure, and results are compared with standard fire exposure.

A Finite Element model (FEM) was developed to simulate the fire performance of Light Gauge Steel Frame (LSF) walls exposed to realistic design fires. The model was developed utilising Abaqus subroutine to incorporate temperature-dependent properties of the material based on the heating and cooling phases of the realistic design fire temperature. The developed model was validated with the available experimental results and incorporated into a parametric study to evaluate the fire performance of conventional LSF walls compared to LSF walls with lightweight concrete filling under standard and realistic fire exposures.

Novel FEM was developed incorporating temperature and phase (heating and cooling) dependent material properties in simulating the fire performance of structures exposed to realistic design fires. The validated FEM was utilised in the parametric study, and results exhibited that the LSF walls with lightweight concrete have shown better fire performance under insulation and load-bearing criteria in Eurocode parametric fire exposure. Foamed Concrete (FC) of 1,000 kg/m3 density showed best fire performance among lightweight concrete filling, followed by FC of 650 kg/m3 and Autoclaved Aerated Concrete (AAC) 600 kg/m3.

The developed FEM is capable of investigating the insulation and load-bearing fire ratings of LSF walls. However, with the availability of the elevated temperature mechanical properties of the LSF wall, materials developed model could be further extended to simulate the complete fire behaviour.

LSF structures are popular in building construction due to their lightweight, easy erecting and constructability characteristics. However, due to steel-lipped channel sections negative fire performance, cavity insulation materials are utilised in the LSF configuration to enhance its fire performance. The lightweight concrete filling in LSF is a novel idea that could be practically implemented in the construction, which would enhance both fire performance and the mechanical performance of LSF walls.

Limited studies have investigated the fire performance of structural elements exposed to realistic design fires. Numerical models developed in those studies have considered a similar approach as models developed to simulate standard fire exposure. However, due to the heating phase and the cooling phase of the realistic design fires, the numerical model should incorporate both temperature and phase (heating and cooling phase) dependent properties, which was incorporated in this study and validated with the experimental results. Further lightweight concrete filling in LSF is a novel technique in which fire performance was investigated in this study.

This paper aims to deal with numerical modelling of composite panels of naval industry exposed to fire. Finite element (FE) analyses have been used to study the thermomechanical behaviour of structures. This paper focuses more particularly on assumptions used to model and evaluate design performance of sandwich panels made of E-Glass vinyl ester and balsawood cored submitted to a certification fire test.

The methodology consisted of having an advanced understanding of phenomena occurring in both thermal and mechanical behaviours when large structures are degraded under thermal solicitation. Then, properties measuring methods were explored and studied in relation with the size of the structure they are used to describe. Finally, several modelling strategies were compared and applied to large-size panels under ISO 834 fire conditions.

Research studies and comparisons showed that for these types of material and these types of structure, non-linear thermomechanical behaviour can be performed with a so-called “reduced” thermal model, provided that properties are measured in an appropriate way. “Reduced” model was compared with “full” model, and results were close to experimental measures. A mechanical properties’ review allowed selecting only necessary material FE analysis of large panels under ISO 834 fire.

The research was conducted on real-size structures taking into account the real conditions in which structures are tested when passing certification. Work was carried out on reducing numerical model size without neglecting phenomenon or losing accuracy.

Standard fire resistance curves such as ASTM E119 have been used for so long in structural fire practice. The issue with use of these curves that they do not represent real fire scenarios. As a result, the alternatives have been to either conduct experiments or find other tools to represent a real fire scenario. Therefore, the purpose of this paper is to understand the temperature effects resulted from a designed fire on steel beams and whether the standard fire curves represent a designed fire scenario.

Computational fluid dynamics (CFD) models were developed to simulate a designed fire scenario and to understand the structural responses on the beams under elevated temperatures. Consequently, the results obtained from the CFD models were compared with the results of three-dimensional (3D) non-linear finite element (FE) models developed by other researchers. The developed FE models were executed using a standard fire curve (ASTM E119). A parametric study including two case studies was conducted.

Results obtained from performing this study showed the importance of considering fire parameters such as fuel type and flame height during the thermal analysis compared to the standard fire curves, and this might lead to a non-conservative design as compared to the designed fire scenario. The studied cases showed that the steel beams experienced more degradation in their fire resistance at higher load levels under designed fires. Additionally, the models used the standard fire curves underestimated the temperatures at the early stages.

This paper shows results obtained by performing a comparison study of models used ASTM E119 curve and a designed fire scenario. The value of this study is to show the variability of using different fire scenarios; thus, more studies are required to see how temperature history curves can be used to represent real fire scenarios.

THE SUBJECT OF FIRE EXTINGUISHING is always of importance to those of our readers who use oil in bulk, whether fuel or lubricating oil. Studies with small ‘model’ fires at the National Bureau of Standards, U.S.A., will therefore be of interest. This work provides additional basic knowledge on the effectiveness of chemical powders as extinguishing agents. In these experiments, the relative extinguishment effect of various dry chemical powders was measured by means of model heptane fires of 1⅛, 6 and 22.8 in. dia. and results have been discussed by T. G. Lee and Dr. A. F. Robertson. Although this type of information can be obtained by studying full‐scale fires, the cost is excessive. In the studies at the Bureau one objective was to find a correlation between the extinction effectiveness of a powder and the size of the fire model.