Hydrocarbon Fire Research Articles

Thermal and Structural Behaviour of Offshore Structures with Passive Fire Protection

In offshore structures, hydrocarbon fires cause the structure to loose its rigidity rapidly and this leads to structural integrity and stability problems. The Passive Fire Protection (PFP) system slows the transfer rate of fire heat and helps to prevent the collapse of structures and human losses. The vital design factors are decided in the detailed design stage. The determined design thickness must be accurately applied in the fabrication yard. However, there are many cases that the PFP is overused because of various reasons. This excessive application of the PFP is an unavoidable problem. Several studies have been conducted on the efficient application and optimal design of the PFP. However, the strength of the PFP has not been considered. In addition, research studies on the correlation between the thickness of the PFP and the structural behaviour are not widely available. Therefore, this study attempts to analyse the thermal and mechanical effects of the PFP on the structure when it is applied to the structural member. In particular, it is intended to determine the change in the behaviour of the structural member as the thickness of the PFP increases.

Numerical and Experimental Analysis of Fire Resistance for Steel Structures of Ships and Offshore Platforms

The requirements for the fire resistance of steel structures of oil and gas facilities for transportation and production of hydrocarbons are considered (structures of tankers and offshore platforms). It is found that the requirements for the values of fire resistance of structures under hydrocarbon rather than standard fire conditions are given only for offshore stationary platforms. Experimental studies on the loss of integrity (E) and thermal insulating capacity (I) of steel bulkheads and deck with mineral wool under standard and hydrocarbon fire regimes are presented. Simulation of structure heating was performed, which showed a good correlation with the experimental results (convective heat transfer coefficients for bulkheads of class H: 50 W/m2·K; for bulkheads of class A: 25 W/m2·K). The consumption of mineral slabs and endothermic mat for the H-0 bulkhead is predicted. It is calculated that under a standard fire regime, mineral wool with a density of 80–100 kg/m2 and a thickness of 40 to 85 mm should be used; under a hydrocarbon fire regime, mineral wool with a density above 100 kg/m2 and a thickness of 60–150 mm is required. It is shown that to protect the structures of decks and bulkheads in a hydrocarbon fire regime, it is necessary to use 30–40% more thermal insulation and apply the highest density of fire-retardant material compared to the standard fire regime. Parameters of thermal conductivity and heat capacity of the applied flame retardant in the temperature range from 0 to 1000 °C were clarified.

Штукатурные составы как огнезащита стальных конструкций объектов нефтегазового комплекса

Purpose. The article describes experimental studies of steel columns samples with two types of fire resistant plasters to determine time of reaching critical temperature and loss of bearing capacity by samples. Methods. Experimental studies of two plaster compositions types, each of which is a mixture of Portland cement, vermiculite and other binders with target additives and fillers have been conducted. The ELCUT software package has been used to simulate thermophysical processes of the considered steel structures. Findings. Simulation of steel structures heating has showed a good correlation (not more than 5 %) with the results of the experiment. Thermophysical characteristics of plaster fire resistant coatings in the temperature range from 20 to 1 000 °C have been determined by solving the inverse task of thermal conductivity using the finite-element model in the ELCUT software package. Nomograms of steel structures heating under the influence of standard and hydrocarbon regimes of the fire with use of plaster composition have been given. Research application field. The obtained results can be used in the technical documentation of fire resistant compositions done by manufacturers for the possibility of simulating and forecasting plaster coating consumption depending on the given thickness of the metal. Conclusions. It has been shown that the difference of thermal conductivity values under standard and hydrocarbon fire conditions at 1 000 °С is 8–10 %, the difference of heat capacity values at 1 000 °С is 10–15 %. It has been found that the fire-resistance limit in the hydrocarbon fire regime is observed 40–50 minutes earlier with comparable flow rates and given metal thicknesses.

AN ADVANCED PROCEDURE FOR THE QUANTITATIVE RISK ASSESSMENT OF OFFSHORE INSTALLATIONS IN EXPLOSIONS

Hydrocarbon explosion and fire are typical accidents in the offshore oil and gas industry, sometimes with catastrophic consequences such as casualties, property damage and pollution. Successful engineering and design should meet both functional requirements associated with operability in normal conditions and health, safety, environmental and ergonomics (HSE&E) requirements associated with accidental and extreme conditions. A risk-based approach is best for successful design and engineering to meet HSE&E requirements. This study aimed to develop an advanced procedure for assessing the quantitative risk of offshore installations in explosions. Unlike existing industry practices based on prescriptive rules or qualitative approaches, the proposed procedure uses an entirely probabilistic approach. The procedure starts with probabilistic selection of accident scenarios. As the defining components of risk, both the frequency and consequences associated with selected accident scenarios are computed using the most refined technologies. Probabilistic technology is then applied to establish the relationship between the probability of exceedance and the physical values of the accident. Acceptance risk criteria can be applied to define the nominal values of design and/or level of risk. To validate and demonstrate the applicability of the proposed procedure, an example of its application to topside structures of an FPSO unit subjected to hydrocarbon explosions is detailed. The conclusions and insights obtained are documented.

A comparative analysis of the requirements of Russia and the United States to the fire resistance of building structures of oil refineries and petrochemical plants

Introduction. Currently, national standards and codes of practice contain deterministic values of the fire resistance of building structures of facilities of the Russian fuel and energy complex (FEC), while a probabilistic approach to determining their fire resistance is not specified in the Russian regulatory documents. The methodology of the probabilistic approach to the fire resistance of structures is detailed in API 2218 “Fireproofing Practices in Petroleum and Petrochemical Processing Plants”, developed by the American Petroleum Institute.Methods. A comparative analysis of the Russian regulatory documents on fire safety and API 2218 in terms of the established concepts of fireproofing and requirements for the fire resistance limits of building structures of oil and gas industry facilities, is carried out.Results. It was established that the Russian Federation has no regulatory documents establishing methods based on the probabilistic approach, including determination of the required fire resistance limits and points of application of fire-resistant coatings at facilities of the fuel and energy complex by analogy with international standard API 2218.Conclusion. Based on the analysis, it was concluded that approaches to the philosophy of the fire resistance of structures of buildings and structures of the fuel and energy complex in the documents under consideration are fundamentally different. In order to improve the Russian regulatory and technical framework, governing fire safety and fire resistance, it is proposed to consider the requirements of foreign documents that take into account proven international engineering and technical practices, in particular, the use of a probabilistic approach taking into account hydrocarbon fires.

Fire Protection of Steel Structures with Epoxy Coatings under Cryogenic Exposure

Cases of fire with highly flammable, combustible liquids and combustible gases with high potential heat emission at oil and gas facilities are assumed to develop as a hydrocarbon fire, which is characterized by the temperature rising rapidly up to 1093 ± 56 °C within five minutes from the test start and staying within the same range throughout the test, as well as by overpressure being generated. Although various fireproof coating systems are commonly used to protect steel structures from high temperatures, a combination of fire protection and cryogenic spillage protection, i.e., protection from liquefied natural gas (LNG), is rather an international practice novelty regulated by standards ISO 20088. Thanks to their outstanding features, i.e., ability to sustain chemical and climatic impact, these epoxy-based materials are able to ensure positive fireproof performance for steel structures in the case of potential cryogenic impact. The article discusses tests on steel structures coated with epoxy fireproof compounds, specifically PREGRAD-EP, OGRAX-SKE and Chartek 2218. The test records show the time from the start of cryogenic exposure to the said sample reaching the limit state, as well as the time from the start of heat impact to the sample reaching the limit state in case of hydrocarbon fire temperature.

The application efficiency of intumescent coatings for power cables of safety systems of nuclear power plants under fire conditions

Introduction. The reliable operation of safety systems, that allows for the failure of no more than one safety system component, entails the safe shutdown and cool-down of an NPP reactor in the event of fire. However, the co-authors have not assessed the loss of performance by an insulating material, treated by intumescent compositions and used in the power cables of the above safety systems exposed to the simultaneous effect of various modes of fire and current loads.Goals and objectives. The purpose of the article is the theoretical assessment of the application efficiency of intumescent fire-retardant coatings in power cables used in the safety systems of nuclear power plants having water-cooled and water-moderated reactors under fire conditions. To achieve this goal, the temperature of the outer surface of the insulation and the intumescent fire-retardant coating was analyzed depending on the mode of fire. Theoretical foundations. A non-stationary one-dimensional heat transfer equation is solved to identify the temperature distribution inside the multilayered insulation and the fire-protection layer of a conductive core.Results and their discussion. The co-authors have identified dependences between the temperature of the outer surface of the insulation and the fire retarding composition of the three-core cable VVGng (A)-LS 3x2.5-0.66, on the one hand, and the temperature of the indoor gas environment for three standard modes of fire and one real fire mode. It is found that before the initiation of the process of destruction of the insulation material, the intumescence of the fire-retardant coating occurs only in case of a hydrocarbon fire. Under real fire conditions, the maximal insulation melting time before the initiation of intumescence of the fire-retardant coating at the minimal temperature of intumescence is 4.75 minutes, while the maximal time period from the initiation of destruction of the insulation material to the moment of the insulation melting is 6.0 minutes.Conclusions. An experimental or theoretical substantiation of parameters of intumescent fire retardants, performed using standard modes of fire, has proven the potential loss of operational properties by insulating materials of power cables, used in the safety systems of nuclear power plants, in case of a real fire. Therefore, it is necessary to establish a scientific rationale for the efficient use of fire retardants in the above cables with regard for the conditions of a real fire.

Sonolytic destruction of Per- and polyfluoroalkyl substances in groundwater, aqueous Film-Forming Foams, and investigation derived waste

Per- and polyfluoroalkyl substances (PFASs) are anthropogenic amphipathic heat-resistant materials found in some household products and Aqueous Film-Forming Foams (AFFFs) used to extinguish hydrocarbon fires. There is a critical need for developing destructive technologies for the treatment of PFAS-impacted waters because several PFASs are classified as probable carcinogens and endocrine disruptors. We tested the destruction of 7 individual PFASs, a mix of 24 native PFASs (24Mix), and samples of AFFF and concentrated Investigation Derived Waste (IDW) by high-frequency ultrasound (700 kHz – 1040 W) in deionized water, groundwater containing low total dissolved solids (TDS) (388 mg L−1), and high-TDS groundwater (10.2 g L−1). This study demonstrated the degradation of novel PFASs, hexafluoropropylene oxide dimer acid (HFPO-DA) and 6:2 fluorotelomer sulfonamidoalkyl betaine (6:2 FTAB), with near-stoichiometric fluoride release. The salts and surfactants affect the air-water partitioning coefficients of PFASs and their availability at the ultrasonic cavity, thereby affecting the degradation rates. The degradation rates of sulfonates and short-chain PFASs were 30% to 60% higher in low TDS groundwater than those in deionized water, while the rates were lower in high TDS groundwater. The degradation rates of sulfonates in AFFF were 40% to 60% higher as compared to the 24Mix. The treatment of concentrated, high-TDS IDW resulted in significant defluorination of 41 PFASs, consuming 3 kWh g−1 – 76 kWh g−1 whereas dilute AFFF degradation utilized 5900 kWh g−1. The results inform important parameters for designing and operating ultrasonic reactors for the degradation of PFASs and verify that sonolytic treatment of concentrated PFAS mixtures and AFFF IDWs can effectively degrade and defluorinate PFASs without the formation of disinfection by-products.

Fire resistance of 3D printed concrete composite wall panels exposed to various fire scenarios

PurposeFire 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.Design/methodology/approachThe 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).Findings3DPC 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.Research limitations/implicationsTo 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.Originality/valueAt 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.

Evaluation of fire performance of lightweight concrete wall panels using finite element analysis

PurposeIn this study, the insulation fire ratings of lightweight foamed concrete, autoclaved aerated concrete and lightweight aggregate concrete were investigated using finite element modelling.Design/methodology/approachLightweight 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.FindingsIt 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.Originality/valueFinding 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.

Modeling of Non-Stationary Heating of Steel Plates with Fire-Protective Coatings in Ansys under the Conditions of Hydrocarbon Fire Temperature Mode

The results of the experimental determination of temperature from a non-heating surface of steel plates with a fire-protective coating under conditions of fire exposure under the hydrocarbon fire temperature regime are presented. A calculated finite element model of the system “steel plate-flame retardant” was constructed to simulate the non-stationary heating of such a system in the ANSYS R17.1 software complex. The reliability of the numerical simulation results is estimated by real test, the adequacy of the developed model to the real processes occurring when heating the steel plates with fire-protective coating under the conditions of hydrocarbon fire temperature mode is made.

The research into the heating effect of secondary steel structures, having no fire proofing, on the fire resistance of fireproof steel beams

Introduction.The international practice of passive fire protection design, as well as some manufactures of fireproofing products recommend to apply fire proofing substances not only to the main element, whose fire resistance limit is standardized, but also to the elements that do not fall under any fire resistance standards. Various support brackets, pipeline supports (hereinafter — PS), etc. can serve as examples. They are not considered as bearing elements according to SP (Construction Regulations) 2.13130.2020, although they are connected to the structures that have fireproofing applied. It is recommended to apply fireproofing substances to such PS within the range of, at least, 450 mm from the point of attachment to the fireproof structure when the area of the PS cross section exceeds 3,000 mm2. No “supplementary” fireproofing is required by the Russian design and fire protection regulations.The subject of research.A change in the fire resistance limit of steel i-girders, caused by the PS heating, depends on the area of the PS cross section and the location of the point of its attachment.The goal.The goal of the research is to analyze the effect, produced by the area of the cross section and the point of attachment, on the fire resistance limit of fireproof steel i-girders in the course of heating.Materials and methods.ANSYS Workbench 2020 R2 (student version) was applied to perform the numerical simulation.Results.The simulation has shown that the PS, having no fireproofing, influences the fire resistance limit of fireproof structures.Conclusions.Currently available methods of analysis of the fire resistance of steel structures take no account of the fire resistance limit reduction, caused by the heating of the PS that has no fireproofing. The numerical simulation has shown that the fire proofing design must take account of the potential reduction in the fire resistance limit of fireproof structures, exposed to the heated PS that has no fire proofing. The further verification of the effect, produced by the PS, that has no fireproofing, on the time to the limit state of a fireproof steel i-girder requires fire tests and supplementary investigations to evaluate the influence of the PS on the heating of vertical fireproof constructions, including the case of the hydrocarbon fire mode.

Review of up-to-date approaches for extinguishing oil and petroleum products

The paper provides a review of up-to-date approaches for extinguishing oil and petroleum products. The variability of extinguishing methods and fire extinguishing agents is noted. Fire extinguishing agents used in extinguishing petroleum products are considered in more detailed way, and their environmental characteristics are discussed. The ambiguity of using various foams for extinguishing the fire is shown. A new method for extinguishing oil and petroleum products, based on the acoustic effect, and the capabilities of acoustic fire extinguishers for preventing and eliminating the combustible hydrocarbon fires, and their identification are analyzed. The further development of known approaches and the simultaneous emergence of innovative methods for extinguishing oil and petroleum products are shown. Keywords: oil; petroleum products; extinguishing agent; environmental characteristics; extinguishing foam; acoustic method.

Numerical Investigation of Residual Strength of Steel Stiffened Panel Exposed to Hydrocarbon Fire

Numerical Investigation of Residual Strength of Steel Stiffened Panel Exposed to Hydrocarbon Fire

Knowledge-enhanced data-driven models for quantifying the effectiveness of PP fibers in spalling prevention of ultra-high performance concrete

Ultra-high performance concrete (UHPC) shows volumetric instability at high temperatures because of explosive spalling. Polypropylene (PP) fibers are effective in mitigating the explosive spalling of UHPC; however, the threshold PP fiber dosage to prevent explosive spalling of UHPC remains unascertained. In this work, a knowledge-enhanced data-driven machine learning method is proposed to quantify the effectiveness of PP fibers in preventing fire-induced spalling of UHPC. Based on the knowledge-enhanced technique, the training data size is increased from 244 to 1642. The prediction accuracy of the artificial neural network (ANN) and extreme gradient boosting (XGBoost) models on 54 groups of unseen data is increased by more than 10% after the training data augment. The well-validated ANN model is then used to determine the threshold PP fiber dosage of UHPC tunnel lining under hydrocarbon fire conditions. The analysis results show that as high as 3.5 kg/m3 PP fibers are required to eliminate explosive spalling of UHPC, but this critical dosage can be lowered to 2.5 kg/m3 by limiting the silica fume replacement level.

Fossil Versus Nonfossil CO Sources in the US: New Airborne Constraints From ACT‐America and GEM

AbstractCarbon monoxide (CO) is an ozone precursor, oxidant sink, and widely used pollution tracer. The importance of anthropogenic versus other CO sources in the US is uncertain. Here, we interpret extensive airborne measurements with an atmospheric model to constrain US fossil and nonfossil CO sources. Measurements reveal a low bias in the simulated CO background and a 30% overestimate of US fossil CO emissions in the 2016 National Emissions Inventory. After optimization we apply the model for source partitioning. During summer, regional fossil sources account for just 9%–16% of the sampled boundary layer CO, and 32%–38% of the North American enhancement—complicating use of CO as a fossil fuel tracer. The remainder predominantly reflects biogenic hydrocarbon oxidation plus fires. Fossil sources account for less domain‐wide spatial variability at this time than nonfossil and background contributions. The regional fossil contribution rises in other seasons, and drives ambient variability downwind of urban areas.

Experimental and theoretical studies on the effect of Al(OH)3 on the fire-extinguishing performance of superfine ABC dry powder

A new type of dry powder fire extinguishing agent was prepared, which was called composite superfine dry powder with Aluminum Trihydrate (CSFP-ATH). The CSFP-ATH was characterized by laser particle size analysis, scanning electron microscope (SEM), thermal gravity analyzer (TGA), transform infrared spectroscopy(FTIR) analyzer and differential scanning calorimetry (DSC). The extinguishing performance of different samples was examined in a small-scale experimental platform for the liquid hydrocarbon fire. The tests were proved that the fire-extinguishing performance was as follows: CSFP-ATH > superfine ABC dry powder(SFP) > commercial ABC dry powder(CDP). Besides, the mechanism, kinetics and thermochemical changes in the reaction process were calculated by Gaussian simulation, and the reaction path of the CSFP-ATH with free radicals in the flame was predicted. Experimental and theoretical studies have been proved that the addition of Al(OH)3 can promote the fire extinguishing performance of superfine ABC dry powder.

Inelastic Strength for Fire Resistance of Composite I-Beam Covered by Insulation Material Subjected to Basic Loading Condition

This paper presents a nonlinear numerical study on the moment resistance of composite steel-concrete beam using fire insulation subjected to various fire scenarios and basic loading conditions. The temperature-dependent material properties of fire insulation, concrete and steel were taken into consideration. The nonlinear finite element analysis was done by utilizing a commercial finite element program, ABAQUS. The obtained moment capacity of the composite I-beam from the current fire code was also performed and compared. The results showed that the fire scenarios and the fire insulation thickness have a great influence on the temperature distribution and strength degradation of the composite beam. The capacity of the beam in hydrocarbon fires, which is the most severe scenario, decreases faster than that in ISO834 standard fire and external fire. The fire resistance of the beam increases as the fire insulation thickness increases due to the temperature degradation in the steel beam. The calculated results from the current fire codes give conservative value at normal temperature and low temperature. The current fire codes can give unconservative values at high temperature when there is a great temperature discrepancy between parts of the beam. A new factor was proposed to determine the fire moment resistance of the composite beam with non-uniform temperature.

Fire Protective Glass Fiber Reinforced Concrete Plates for Steel Structures under Different Types of Fire Exposure

In a situation where a fire occurs either in a tunnel with a burning vehicle carrying petroleum products, at an offshore platform, or at an oil and gas asset to be protected, such a case is commonly described using a hydrocarbon fire curve. Therefore, it is extremely important to design construction, which can maintain stability and bearing capacity both under the standard and hydrocarbon fire modes. The purpose in this work is to hold a behavior simulation of a steel structure with fireproofing ensured through lightweight concrete slabs reinforced with fiber glass as well as a validation of the outcomes by assessing the experimental findings obtained from the relevant fire tests. A fire resistance study was carried out here for steel structures with a profile ratio of 156 mm−1 for the cases of a standard fire and of a hydrocarbon fire. A constant static load of 687 kN (70 tf) was taken for standard fire and 294 kN (30 tf) for hydrocarbon fire; the column was under vertical compression with one end resting on a hinged support and the other end rigidly fixed. The specimen design incorporated single-layer box-section cladding made of Pyro-Safe Aestuver T slabs, 40 mm thick and of a 650 kg/m3 density, pre-cut to fit the column size. The column strength loss (R) ultimately occurred after 240 min in the standard fire case and after 180 min in the hydrocarbon fire case. As the breach in the fireproofing structural integrity (E) or the installation accuracy cannot be considered, the limit state indicators may show certain discrepancies. According to the simulation performed using SOFiSTiK software, the design fire resistance rating of the structure in a hydrocarbon fire case was 58% higher than the figure obtained by holding fire tests due to the slabs cracking during the experiment session; the discrepancy between the outcomes of the session and the simulation in a standard fire case was as much as 15%.

Fire response of horizontally curved continuous composite bridge girders

This paper presents an approach for investigating fire response of horizontally curved continuous composite bridge girders under localized hydrocarbon fire exposure conditions, considering flexural-torsional-shear coupling effect. A three-dimensional nonlinear finite element model, established using computer program ANSYS and validated through experimental data generated from fire tests, is utilized to analyse the effects, including curvature radius, fire position along bridge span and fire exposed different steel girders, on fire response of a typically horizontally curved three-span continuous composite bridge girder. The predicted results including mid-span deflection, axial displacement and web out-of-plane displacement in different steel girders, are used to quantitatively evaluate fire resistance of horizontally curved continuous composite bridge girders. Findings from analysis results show that curvature radius, fire position along bridge span and fire exposed different steel girders have a significant influence on fire resistance of horizontally curved continuous composite bridge girders. Horizontally curved composite bridge girder with smaller curvature radius presents a lower fire resistance. The outer steel girder governs failure of horizontally continuous composite curved bridge girders subjected to simultaneously hydrocarbon fire and structural loading. Web buckling-based failure criterion is suited to determine failure of horizontally curved continuous composite bridge girders under fire conditions. Therefore, prevention of the outer steel girder from fire can highly improve fire resistance of horizontally curved continuous composite bridge girders.