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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.

The fire safety of structures is an existing and important design aspect, which is assured by strict regulations. As a means to adhere to the strict requirements, fire protection has become a core problem. It is particularly difficult to comply with these regulations in the case of timber, which is a combustible material. These problems could be solved by enveloping the wood in fire retardant materials. MSZ EN 1995-1-2 currently does not take into consideration the fire-retardant materials charring rate under fire exposure.

However, currently these fire retardants are proving to be reliable and depending on their application can achieve better reaction-to-fire classifications. During the research, the authors used five different fire-retardant materials on three different types of wood and tested their behaviours in a laboratory. When selecting them, it was important to choose the species that are most commonly used in the building industry but which have significantly different densities. Our choice fell upon spruce (360 kg/m³), Scots pine (540 kg/m³) and oak (650 kg/m³). During the tests, we examined the weight reduction and the process of burning on the specimens treated with the fire retardant material. In addition, the authors also performed tests by derivatography on both untreated and treated specimen.

The question is whether the effects of the fire retardants should be taken into consideration when calculating the extent of the burn. The Eurocode (MSZ EN 1995-1-2) does not provide any opinions. On the market, there are manufacturers who are already discussing the possibilities of reducing the burn rate during the qualification of paints. In this paper, based on the results we received, we discuss the beneficial effects of the fire retardants which can be taken into account while measuring cross-sections.

By using fire retardants, a high proportion of cross-sectional area gain is only possible in case of small cross-sections; therefore, it is advisable to use them here as well. This can be effective for example in many smaller cross-sections, when there is a little space and therefore requires a small cross-section. Thus, if a larger cross-section without protection is not possible, it can be replaced by a smaller cross section, treated with a fire retardant.

This paper investigates individual investors' responses to stock underpricing and how their trading decisions are affected by analysts' forecasts and recommendations.

This empirical study uses mutual fund fire sales as an exogenous source that causes stock underpricing and analysts' forecasts and recommendations as price-correcting information. The study further uses regression analysis to examine individual investors' responses to fire sales and how their responses vary with price-correcting information.

The authors first show that individual investors respond to mutual fund fire sales by significantly decreasing net buys, and this effect appears to be prolonged. Next, the authors find that the decrease of net buys diminishes following analysts' price-correcting earnings forecast revisions and stock recommendation changes. Hence, the authors suggest that individual investors are not “wise” enough to recognize flow-driven underpricing; however, this response is weakened by analysts' price-correcting information.

There is an ongoing debate in the literature about whether individual investors should be portrayed as unsophisticated traders or informed traders who can predict future returns. The authors study a unique information event and provide new evidence related to both perspectives. Overall, our evidence suggests that the “unsophisticated traders” perspective is predominant, whereas a better information environment significantly reduces individual investors' information disadvantage. This finding could be of interest to both academic researchers and regulators.

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.

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.

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.

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.

This study focused on identifying critical factors governing the fire response of prestressed hollow-core slabs. The hollow-core slabs used as flooring units can be subjected to elevated temperatures during a fire. The fire response of prestressed hollow-core slabs is required to develop slabs with greater fire endurance. The present study aims to determine the extent to which the hollow-core slab can sustain load during a fire without undergoing progressive collapse under extreme fire and heating scenarios.

A finite element model was generated to predict the fire response of prestressed hollow core slabs under elevated temperatures. The accuracy of the model was predicted by examining thermal and structural responses through coupled temperature displacement analysis. A sensitivity analysis was performed to study the effects of concrete properties on prediction of system response. A parametric study was conducted by varying the thickness of the slab, fire and heating scenarios.

Thermal conductivity and specific heat of concrete were determined as sensitive parameters. The thickness of the slab was identified as a critical factor at a higher load level. Asymmetric heating of the slab resulted in higher fire resistance compared with symmetric heating.

This is the first study focused on studying the effect of modeling uncertainties on the system response by sensitivity analysis under elevated temperatures. The developed model with a parametric study helps in identifying critical factors for design purposes.

In fire condition, the limiting temperature of a restrained steel beam depends on a few parameters, e.g. temperature distributions along and across the beam, beam’s load ratio and span length. The purpose of this study is to investigate the structural fire behaviour of axially restrained steel beams under different beam’s load ratios, taking into consideration the effect of the beam’s end connections configuration.

A three-dimensional finite element (FE) computer model has been developed to simulate the structural fire behaviour of axially restrained steel beams and their end connections. After successfully validating the developed model against the outcomes of the available large-size fire resistance experiments, the FE model has been used in a parametric study to investigate the beam’s load ratio effect on the behaviour of the axially restrained steel beams and their end connections.

The parametric study showed that increasing the beam loading level significantly increased the beam deflections at elevated temperatures; where, increasing the beam’s load ratio from 0.5 to 0.9 reduced the beam fire resistance by about 100 s. In contrast, decreasing the beam’s load ratio from 0.5 to 0.3 allowed the beam to easily achieve a 30-min fire resistance rating with no fire protection applied.

Experimental parametric studies are difficult to control in a laboratory setting and are also expensive and time consuming. Therefore, the reasonable accuracy of the validated FE model in reproducing the experimental fire behaviour of steel beams and their end connections makes it a very useful tool for both numerical and analytical studies.

Most of the numerical research and experiments on composite slabs with a steel deck have been developed to study the effect of fire during the heating phase. This manuscript aims to describe the thermal behaviour of composite slabs when submitted to different fire scenarios, considering the heating and cooling phase.

Three-dimensional numerical models, based on finite elements, are developed to analyse the temperatures inside the composite slab and, consequently, to estimate the fire resistance, considering the insulation criteria (I). The numerical methods developed are validated with experimental results available in the literature. In addition, this paper presents a parametric study of the effects on fire resistance caused by the thickness of the concrete part of the slab as well as the natural fire scenario.

The results show that, depending on the fire scenario, the fire resistance criterion can be reached during the cooling phase, especially for the thickest composite slabs. Based on the results, new coefficients are proposed for the original simplified model, proposed by the standard.

The developed numerical models allow us to realistically simulate the thermal effects caused by a natural fire in a composite slab and the new proposal enables us to estimate the fire resistance time of composite slabs with a steel deck, even if it occurs in the cooling phase.

This paper aims to present an investigation conducted to evaluate the effects of important parameters affecting the structural fire performance of light gauge steel frame (LSF) walls. It also evaluates the applicability of commonly used critical hot flange temperature method to determine the fire resistance ratings (FRR) of different LSF walls.

The effects of important parameters such as stud section profiles and their dimensions, elevated temperature mechanical property reduction factors of the steel used, types of wall configurations and fire curves on the FRR of LSF walls were investigated. An extensive finite element analysis-based parametric study was conducted to evaluate their effects (finite element analysis – FEA). For this purpose, finite element models which were validated using the full-scale fire test results were used. Using the structural capacities obtained from FEAs, the load ratio versus FRR curves were produced for all the different LSF walls considered.

Stud depth and thickness significantly affected the fire performance of LSF walls because of the differences in temperature development pattern, thermal bowing deflections and the failure modes of stud. The FRR of LSF walls increased significantly when steel studs with higher elevated temperature mechanical property reduction factors were used. FRR significantly changed when realistic design fire curves were used instead of the standard fire curve. Furthermore, both the critical hot and average flange temperature methods were found to be unsuitable to predict the FRR of LSF walls.

The developed comprehensive fire performance data would facilitate the development of LSF walls with enhanced fire performance, and, importantly, it would facilitate and advance the successful applications of hollow flange channel section studs in LSF walls.

Forests too thick with fuels that are too continuously spread to resist fire are common throughout the west. After a century or more of actively working to suppress fire across the landscape, we now recognize that fire is a part of our forests, shrublands, and range, and that it will come whether we wish it or not. At last, managers must realize forests cannot be fire-proofed (DellaSala, Williams, Williams, & Franklin, 2004). We must work with fire rather than against it.

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.