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Recent events of fire after an earthquake (FAE) show that this is a frequent dual event leading to a significant loss which can only be reduced by increasing the level of safety. This paper presents numerical models developed for FAE analyses on 24 steel portal frames to investigate their behaviour and estimate the performance in terms of ratios with regard to horizontal displacement, fire resistance time, and critical temperature. In this study, validated numerical models are used for a parametric study to explore the effect of number of bays and stories on the performance of steel frames under two fire scenarios. Frames with one bay and one story are designed with the Algerian seismic code, RPA99v2003, considering the seismic region of Chlef and other frames are checked with Eurocode for the ultimate limit state. All frames subjected to the seismic and the ISO834 fire actions are simulated within a single software, ANSYS, for pushover and thermo-mechanical analyses. The performance is evaluated, by FAE analysis for damaged frames remaining in the plastic state and undamaged frames not reaching the plastic state, and compared to those subjected to fire without earthquake (FWoE). The frames under FAE are more vulnerable to fire and increasing damage is produced and hence reducing their structural performance. The results also show that the higher the number of bays is, the higher the performance of the frames. The critical temperature of beams decreases with the beam length. The frames with FAE, under inelastic conditions, have smaller fire resistance, when compared to undamaged frames.

This paper presented the results of numerical analyses on the fire resistance of composite columns with partially encased steel columns (PEC). This investigation used 2D and 3D finite element models and assessed for the design method of composite elements under compression according to the Annex G of Eurocode 4. New proposals were presented to determine the buckling resistance of PEC under standard fire. The 2D and 3D numerical models were based on American and European steel profiles. The 2D thermal model was used to improve the design method of the current version of the Eurocode 4, enhancing the balance summation model, which is currently used to determine the plastic resistance to axial compression and the effective flexural stiffness of the four components of the cross-section. The 3D thermomechanical model used the temperature field for each fire rating time (30, 60, 90, and 120 min) and applied the incremental load step solution method, based on the Newton–Raphson, to determine the buckling load of partially encased columns with 3 and 5 m, considering different supporting conditions. These results present a safer buckling curve when compared to curve “c”.

The main goal of this study is to assess the behaviour of soil–cement blocks with incorporation of organic wastes. The problem of waste accumulation exists worldwide and has become a concern in today’s society, leading to enormous environmental damage. One of the possibilities for reducing their environmental impact is the reuse of these wastes in new materials. However, incorporating waste changes the mechanical, physical and thermal properties of the new material. In order to evaluate the potential use of waste in blocks composition, laboratory tests were conducted and the results were analysed. This article presents the fire behaviour of ecological soil–cement blocks with waste incorporation. Therefore, an experimental programme was performed using samples of wall panel with soil–cement blocks. The wall specimen under fire conditions was also analysed by a non-linear transient finite element numerical model, in time and temperature domains, and the numerical and experimental temperature fields were compared.

The main objective of this work is to present a numerical model to predict the effect of wood density in unprotected wood connections with an internal steel plate (wood–steel–wood), when comparing with the same connections using passive protection with gypsum plasterboard, submitted to fire conditions. Wood–steel–wood connections are made of four wood members, two on each side, with an internal steel plate that connects the pieces using steel dowel fasteners. First, analytical methodologies according to Eurocode 5 part 1-1 were used to design the connections at room temperature. After that, to predict the fire exposure and the connection ability, a numerical model was performed which permits to compare the fire resistance in wood–steel–wood connections without and with passive protection following the Eurocode 5 part 1-2. Results of the temperature and the wood char layer depth were compared using three different wood densities. The evolution of the charring rate was calculated in different locations of the connections and compared with the analytical value proposed by the Eurocode 5 part 1-2.

The light steel frame walls are mostly used for non-load bearing applications. The light steel framed walls are made with studs and tracks that require fire protection, normally achieved by single plasterboard, by composite protection layers or by insulation of the cavity. The partition walls are fire rated to resist by integrity and insulation. Seven small-scale specimens were tested to define the fire resistance of non-load bearing light steel frame walls made with different materials. All tests were validated using two-dimensional numerical models, based on the finite-element method, the finite-volume method and hybrid finite-element method. A good agreement was achieved between the numerical and the experimental results from fire tests. The fire resistance increases with the number of studs and also with the thickness of the protection layers. The hybrid finite-element method solution method looks to be the best approximation model to predict fire resistance.

Stainless steel has countless desirable characteristics for a structural material. Although initially more expensive than conventional carbon steel, stainless steel structures can be competitive due to their smaller need for fire protection material and lower life-cycle cost, thus contributing to a more sustainable construction. The most common stainless steel groups used in structural applications are the austenitic, ferritic and austenitic–ferritic (also known as Duplex grades). This work presents a numerical study on the behaviour of stainless steel circular hollow section members under axial compression at elevated temperatures, with different cross-section slenderness. The numerically obtained ultimate load-bearing capacities are compared with simplified calculation formulae from Eurocode 3 for columns under fire situation. A parametric study, considering different stainless steel grades from the aforementioned groups, cross-sectional classes and slendernesses, is here presented for different elevated temperatures. The numerical analyses were performed with the finite element programme SAFIR, with material and geometric non-linear analysis considering imperfections.Comparisons between the numerical results and the Eurocode 3 rules demonstrated that a specific design approach must be developed for stainless steel columns under fire situation.

Spanish manufacturer Construcciones y Auxiliar de Ferrocarriles developed an innovative alternative for compartmentation, based on a smoke extraction system, to guarantee safe conditions during evacuation processes in a passenger unit. To demonstrate its performance in a train unit, a real-scale experimental programme, supported by the application of fire computer modelling, was applied in a new Construcciones y Auxiliar de Ferrocarriles’ rolling stock. The new smoke exhaust system aims to extract the smoke generated during a fire in the passenger area by exhaust fans of the heating, ventilation, and air conditioning system, allowing the ingress of fresh exterior air in the lower part of the rear ends of the car. These key elements create an air flow that evacuates the smoke to prevent people from being exposed to it. Full-scale fire tests were developed in the train unit following the Australian standard AS 4391-1999. A fire of 140 kW was used, and the smoke was generated by a clean smoke machine. Measurement points included six thermocouple trees, 10 gas flow velocity probes and two GoPro HD video cameras (for the estimation of the visibility). The system performance was successful with the tenability criteria, since the value of visibility at the non-fire car was greater than 30 m and the temperature was lower than 30°C during all the tests at a height of 1.7 m above the floor. Experimental results were used to validate the computational model. The computational model results show a good accuracy compared with the tests.

A reappraisal of the method based on nominal curvature for designing reinforced concrete columns in fire is proposed, with the focus on the validation of an alternative and widely accepted way of applying the method, which differs from the current provisions of EN 1992-1-2. To this end, a systematic comparison between experimental and numerical results is carried out on a database consisting of 74 columns tested in different laboratories. The comparison shows that the method based on nominal curvature yields conservative estimates of the time to failure. Moreover, the numerical results obtained are reasonably close to those obtained by means of finite element analysis. By contrast, if the method is applied in combination with the simplified methods introduced in EN 1992-1-2, the numerical results are not conservative, with a significant overestimation of the bearing capacity of the columns, and of the time to failure, mainly because of the overestimation of the stiffness by the simplified methods.

The fire resistance of composite slabs with steel decking, in Europe, is usually defined using simple calculation models provided by the Eurocode EN 1994-1-2. For assessing the methodology of these simple calculation methods, a new advanced calculation method is presented, using the software ANSYS. The numerical model is first validated with experimental data reported on bibliography and then a parametric analysis is conducted to better understand the effect of the load level on the composite structure under fire. The validation of the simulations consisted of three different models: the first model considers perfect contact between the steel deck and the concrete topping, and the two following models consider the existence of an air gap between these materials, acting as a thermal resistance on the temperature field through the thickness of the slab. The numerical results show good approximation to the experimental results, mainly when using the non-perfect contact model, reaching 3.88% and 16.91% of difference with respect to the insulation and load-bearing criteria, respectively. Based on the validation models, a parametric study is presented, modifying the load level from 10% up to 75%. New simple calculation models are presented to define the fire resistance of composite slabs, considering the load level, and the debonding effect between the concrete and the steel deck.

Composite structures made from the combination of steel profile and concrete have significant loadbearing capacity which depends on the behaviour of the two material components and their interaction, particularly in fire conditions. It is not possible to assess the fire resistance of composite members only by considering the temperature of the steel, because the presence of the concrete may contribute greatly to increase the resistance, strength and thermal inertia of the member, which improves consequently the fire behaviour of the element. The aim of this work is to develop an efficient non-linear 3D finite element model to investigate the behaviour of pin-ended axially loaded composite column made from high strength concrete (HSC) and normal strength concrete (NSC) at different fire rating classes. Two types of column section were selected, notably HEB 160 profile totally encased with concrete and HEB220 partially encased with concrete. The fire behaviour of the columns was tested according to ISO834 standard fire. The results show that the use of HSC in composite columns reduces the level of fire protection with the regard to NSC. NSC in composite structures accommodates higher deflections than HSC, which is safer in case of fire accident. The mechanical resistance in composite columns at room temperature is reduced more than twice after 30 min of fire exposure.