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This paper aims to present results from numerical studies on the response of fire exposed composite girders subjected to dominant flexural and shear loading. A finite element-based numerical model was developed to trace the thermal and structural response of composite girders subjected to simultaneous structural loading and fire exposure. This model accounts for various critical parameters including material and geometrical nonlinearities, property degradation at elevated temperatures, shear effects, composite interaction between concrete slab and steel girder, as well as temperature-induced local buckling. To generate test data for validation of the model, three composite girders, each comprising of hot-rolled (standard) steel girder underneath a concrete slab, were tested under simultaneous fire and gravity loading.

The validated model was then applied to investigate the effect of initial geometric imperfections, load level, thickness of slab and stiffness of shear stud on fire response of composite girders.

Results from experimental and numerical analysis indicate that the composite girder subjected to flexural loading experience failure through flexural yielding mode, while the girders under shear loading fail through in shear web buckling mode. Further, results from parametric studies clearly infer that shear limit state can govern the response of fire exposed composite girders under certain loading configuration and fire scenario.

This paper presents results from numerical studies on the response of fire exposed composite girders subjected to dominant flexural and shear loading.

This review paper seeks to enhance knowledge of how pre-loading affects reinforced concrete (RC) beams under fire. It investigates key factors like deflection and load capacity to understand pre-loading's role in replicating RC beams' actual responses to fire, aiming to improve fire testing protocols and structural fire engineering design.

This review systematically aggregates data from existing literature on the fire response of RC beams, comparing scenarios with (WP) and without pre-loading (WOP). Through statistical tools like the two-tailed t-test and Mann–Whitney U-test, it assesses deflection extremes. The study further examines structural responses, including flexural and shear behavior, ultimate load capacity, post-yield behavior, stiffness degradation and failure modes. The approach concludes with a statistical forecast of ideal pre-load levels to elevate experimental precision and enhance fire safety standards.

The review concludes that pre-loading profoundly affects the fire response of RC beams, suggesting a 35%–65% structural capacity range for realistic simulations. The review also recommended the initial crack load as an alternative metric for determining the pre-loading impact. Crucially, it highlights that pre-loading not only influences the fire response but also significantly alters the overall structural behavior of the RC beams.

The review advances structural fire engineering with an in-depth analysis of pre-loading's impact on RC beams during fire exposure, establishing a validated pre-load range through thorough statistical analysis and examination of previous research. It refines experimental methodologies and structural design accuracy, ultimately bolstering fire safety protocols.

Earthquake tremors not only increase the chances of fire ignition but also hinder the fire-fighting efforts due to the damage to the lifelines of a city. Most of the international codes have independent recommendations for structural safety against earthquake and fire. However, the possibility of a multi-hazard event, such as fire following an earthquake is seldom addressed.

This paper presents an experimental study of Reinforced Concrete (RC) columns in post-earthquake fire (PEF) conditions. An experimental approach is proposed that allows the testing of a column instead of a full structural frame. This approach allows us to control the loading and boundary conditions individually and facilitates the testing under a variety of these conditions. Also, it allows the structure to be tested until failure. The role of parameters, such as earthquake intensity, axial load ratio and the ductile detailing of the column on the earthquake damage and subsequently the fire performance of the structure, is studied in this research. Six RC column specimens are tested under a sequence of quasi-static earthquake loading, followed by combined fire and axial compression loading conditions.

The experiment results indicate that ductile detailed columns subjected to 4% or less lateral drift did not lose significant load-carrying capacity in fire conditions. A lateral drift of 6% caused significant damage to the columns and reduced the load-carrying capacity in fire conditions. The level of the axial load acting on the column at the time of earthquake loading was found to have a very significant effect on the extent of damage and reduction in column load capacity in fire conditions. The columns that were not detailed for a ductile behavior observed a more significant reduction in axial load carrying capacity in fire conditions.

This study is limited to columns of 230 mm size due to the limitations of the test setup. The applicability of these findings to larger column sections needs to be verified by developing a numerical analysis methodology and simulating other post-earthquake-fire tests available in the literature.

The experimental procedure proposed in this paper offers an alternative to the testing of a complete structural frame system for PEF behavior. In addition to the ease of conducting the tests, the procedure also allows much better control over the heating, structural loading and boundary conditions.

The primary purpose of this research was to expand the knowledge base regarding the behavior of steel columns during exposure to fire. This paper presents the numerical study of the effect of heat on the performance of parking steel column in a seven-story steel building under cyclic loading.

In this research, the forces and deformations developed during a fire are estimated by using detailed 3D finite-element models. The analyses are in the form of a coupled thermo-mechanical analysis in two types of loading: concurrent loading (fire and cyclic loading) and non-concurrent loading (first fire and then cyclically), and the analyses have been conducted in both states of the fire loading with cooling and without cooling using the ABAQUS software. Further, it was investigated whether, during the fire loading, the specimen was protected by a 3-cm-thick concrete coating and how much it changes the seismic performance. After verification of the specimen with the experimental test results, the column model was investigated under different loading conditions.

The result of analyses indicates that the effect of thermal damage on the performance of steel columns, when cooling is happening late, is more than the state in which cooling occurs immediately after the fire. In this paper, thermal–seismic performance of parking steel columns has been specified and the effect of the fire damage has been investigated for the protected steel by concrete coating and to the non-protected steel, under both cooling and non-cooling states.

This study led to recommendations based on the findings and suggestions for additional work to support performance-based fire engineering. It is clear that predicting force and deformation on steel column during fire is complex and it is affected by many variables. Here in this paper, those variables are examined and proper results have been achieved.

Concrete arch structures are commonly constructed for various civil engineering applications. Despite their frequent use, there is a lack of research on the response and performance of concrete arches when subjected to fire loading. Hence, this paper aims to investigate the response and in-plane failure modes of shallow circular concrete arches subjected to mechanical and fire loading.

This study is conducted through the development of a three-dimensional finite element (FE) model in ANSYS. The FE model is verified by comparison to a non-discretisation numerical model derived herein and the reduced modulus buckling theory, both used for the non-linear inelastic analysis of shallow concrete arches subjected to uniformly distributed radial loading and uniform temperature field. Both anti-symmetric and symmetric buckling modes are examined, with analysis of the former requiring geometric imperfection obtained by an eigenvalue buckling analysis.

The FE results show that anti-symmetric bifurcation buckling is the dominant failure mode in shallow concrete arches under mechanical and fire loading. Additionally, parametric studies are presented which illustrate the influence of various parameters on fire resistance time.

Fire response of concrete arches has not been reported in the open literature. The authors have previously investigated the stability of shallow concrete arches subjected to mechanical and uniform thermal loading. It was found that temperature greatly reduced the buckling loads of concrete arches. However, this study was limited to the simplifying assumptions made which include elastic material behaviour and uniform temperature loading. The present study provides a realistic insight into the fire response and stability of shallow concrete arches. The findings herein may be adopted in the fire design of shallow concrete arches.

Despite recognizing the significance of risk-based frameworks in fire safety engineering, the usual approach in structural fire design is largely member/component level, wherein effect of uncertainties influencing the fire resistance of structures are not explicitly considered. In this context, a probabilistic framework is presented to investigate the vulnerability of a reinforced concrete (RC) members and structure under fire loading scenario.

The RC structures exposed to fire are modeled in a finite element (FE) platform incorporating material and geometric nonlinearity, in which the transient thermo-mechanical analysis is carried out by suitably incorporating the temperature variation of thermal and mechanical properties of both concrete and steel rebar. The stochasticity in the system is considered in structural resistance, thermal and fire model parameters, and the subsequent fragility curves are developed considering threshold limit state of deflection.

The fire resistance of RC structure is reported to be significantly lower in comparison to the RC members, thereby illustrating the current prescriptive design approaches based on studies of structural member behavior to be crucial from a safety and reliability point of view.

The framework developed for the vulnerability assessment of RC structures under fire hazard through FE analysis can be effectively used to estimate the structural fire resistance for other similar structure to enhance safety and reliability of structures under such extreme threats.

The paper proposes a novel methodology for vulnerability assessment of three-dimensional RC structures under fire hazard through FE analysis and provides comparison of the structural fragility with fragility developed for structural members. Moreover, the research emphasizes to assume 3D behavior of the structure rather than the approximate 2D behavior.

Glass material is largely used for load-bearing components in buildings. For this reason, standardized calculation methods can be used in support of safe structural design in common loading and boundary conditions. Differing from earlier literature efforts, the present study elaborates on the load-bearing capacity, failure time and fire endurance of ordinary glass elements under fire exposure and sustained mechanical loads, with evidence of major trends in terms of loading condition and cross-sectional layout. Traditional verification approaches for glass in cold conditions (i.e. stress peak check) and fire endurance of load-bearing members (i.e. deflection and deflection rate limits) are assessed based on parametric numerical simulations.

The mechanical performance of structural glass elements in fire still represents an open challenge for design and vulnerability assessment. Often, special fire-resisting glass solutions are used for limited practical applications only, and ordinary soda-lime silica glass prevails in design applications for load-bearing members. Moreover, conventional recommendations and testing protocols in use for load-bearing members composed of traditional constructional materials are not already addressed for glass members. This paper elaborates on the fire endurance and failure detection methods for structural glass beams that are subjected to standard ISO time–temperature for fire exposure and in-plane bending mechanical loads. Fire endurance assessment methods are discussed with the support of Finite Element (FE) numerical analyses.

Based on extended parametric FE analyses, multiple loading, geometrical and thermo-mechanical configurations are taken into account for the analysis of simple glass elements under in-plane bending setup and fire exposure. The comparative results show that – in most of cases – thermal effects due to fire exposure have major effects on the actual load-bearing capacity of these members. Moreover, the conventional stress peak verification approach needs specific elaborations, compared to traditional calculations carried out in cold conditions.

The presented numerical results confirm that the fire endurance analysis of ordinary structural glass elements is a rather complex issue, due to combination of multiple aspects and influencing parameters. Besides, FE simulations can provide useful support for a local and global analysis of major degradation and damage phenomena, and thus support the definition of simple and realistic verification procedures for fire exposed glass members.

Accidental loadings such as fire constitute a great majority of potential and actual fatalities in both onshore and offshore installations. In order to prevent human loss and for a safe design of an asset, the risk of fire loading needs to be quantified, in terms of both probability/frequency and consequence aspects. In this paper the authors propose a novel risk-based approach for the assessment against accidental fire loading.

In a conventional passive fire protection (PFP) analysis using ductility level analysis (DLA), fire loads are deterministically applied to a structure whose response is then analyzed. The initial PFP scheme is developed based on the analysis and then optimized. This approach is sometimes misinterpreted as a “risk-based” approach; however, it does not take into account the frequency aspect of the risk assessment. In a risk-based PFP analysis using DLA, fire scenarios are developed in a particular target zone. Then DLA is performed to determine the structural consequence. If personnel safety is of interest, the consequence of the structure is then linked to individual risk (IR) to determine fatalities. The amount of PFP to be applied on the structure is fully based on the risk that is produced by the fire scenarios in target zones.

A new perspective on safe design of onshore/offshore structures for accidental loadings is outlined to estimate the associated risk to potential targets such as personnel as well as asset. The proposed assessment methodology will contribute toward identifying the mitigation measures and safety-critical procedures and equipment and toward a safer design.

This paper presents a new perspective in a safer design of onshore and offshore structures for a fire accidental loading based on risk calculation. Risk is defined as a combination of the frequency and consequence. An event frequency analysis is carried out to determine how often one should expect the event to occur. A consequence analysis is carried out to determine the severity levels of the event. In a risk-based consequence analysis, the severity levels are fully determined based on the risk associated with the event. The proposed novel risk-based assessment methodology against accidental fire loading contributes toward fully understanding the risk from an impact to personnel and to asset perspectives and leads toward safer and optimal design.

Steel-reinforced concrete-filled steel tubular (SRCFST) columns have been increasingly popular in engineering practice for the columns' excellent seismic and fire performance. Significant design progress guidance has been made through continuous numerical and experimental research in recent years. This paper tested and analysed the residual loading capacity of SRCFST columns under axial loading after experiencing non-uniform ISO-834 standard fire.

The experimental research covered the main parameter of heating conditions, 1-side and 2-side fire, through two specimens. Two specimens were heated and loaded simultaneously in the furnace for 240 min. After cooling, the columns were moved to the hydraulic loading system and loaded to failure to determine the columns' residual capacity.

The experimental results indicated that the non-uniform heating area plays an essential role in the overall performance of SRCFST columns, the increasing heating area of columns results in lower residual loading capacity and stiffness. The SRCFST columns still had a high loading capacity after heating and loading in the fire.

The comparison of experimental data against design results showed that the design method generated a 16% safety margin for S2H4 and a 39% safety margin for S1H4.

Investigate the fire performance of eccentrically loaded concrete partially encased column (PEC), using the advanced calculation method (ANSYS 18.2, 2017) and the simple calculation method in Annex G of Eurocode 4 (EN 1994-1-2, 2005). This work examines the influence of a range of parameters on fire behaviour of the composite column including: eccentricity loading, slenderness, reinforcement, fire rating and fire scenario. In this study, ISO-834 (ISO834-1, 1999) was used as fire source.

Currently, different methods of analysis used to assess the thermal behaviour of composite column exposed to fire. Analytical method named simplified calculation methods defined in European standard and numerical simulations named advanced calculation models are treated in this paper.

The load-bearing capacity of the composite column becomes very weak in the presence of the fire accident and eccentric loading, this recommends to avoid as much as possible eccentric loading during the design of construction building. The reinforcement has a slight influence on the temperature evolution; moreover, the reinforcement has a great contribution on the load capacity, especially in combined compression and bending. When only the two concrete sides are exposed to fire, the partially encased composite column presents a high load-bearing capacity value.

The use of a three-dimensional numerical model (ANSYS) allowed to describe easily the thermal behaviour of PEC columns under eccentric loading with the regard to the analytical method, which is based on three complex steps. In this study, the presence of the load eccentricity has found to have more effect on the load-bearing capacity than the slenderness of the composite column. Introducing a load eccentricity on the top of the column may have the same a reducing effect on the load-bearing capacity as the fire.