Research heating of the steel i-beam rods with mineral wool coating under the conditions of standard temperature fire regime

2020 ◽  
pp. 116-126
Author(s):  
S.V. Pozdieiev ◽  
◽  
O.M. Nuianzin ◽  
S.O. Sidnei ◽  
A.Y. Novhorodchenko ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Fire Resistance ◽  
Fire Retardant ◽  
Steel Structure ◽  
Steel Structures ◽  
Mineral Wool ◽  
Fire Tests ◽  
Standard Temperature ◽  
Steel Columns ◽  
The Moment

In the article, experimental fire tests on establishing maximum fire resistance of the steel columns with fire-retardant mineral wool covering are analyzed. The scientific novelty of this study are the new method developed for manufacturing and shaping samples of the steel columns with fire-retardant mineral wool covering, and the method developed for conducting fire tests on establishing patterns of dependence of the moment when steel columns with the fire-retardant cladding lose their bearing capacity down to the limit. The subject of the study was an influence of design parameters of the fire-retardant cladding on the results of the estimated fire resistance of the steel columns under the influence of the standard fire temperature mode. The main task of the research described in this article was to determine a moment of the peak critical temperature of fire-retardant steel structure depending on the thickness of the mineral wool covering. The test results of samples of steel columns with different thickness of fire-retardant cladding based on mineral wool covering are also described in the article; the tests were carried out in accordance with the developed methodology of experimental studies. The repeatability of the time indicators of the bearing capacity loss by the tested samples of steel columns with fire-retardant cladding depending on the duration of the sample exposure to the action of the fire standard temperature is shown. The obtained research results will allow to create a mathematical model for predicting a dependence of the moment when a steel structure reaches its critical temperature depending on the thickness of the fire-retardant cladding. The constructed mathematical model can be considered as a scientific basis for the creation of new engineering methods of calculation for assessing fire resistance of the steel structures with fire-retardant mineral wool covering. These engineering and calculation methods allow improving the regulatory acts for designing of the fire-resistant steel structures.

EVALUATION OF FIRE RESISTANCE OF FIRE PROTECTED STEEL STRUCTURES

2021 ◽  
pp. 149-158
Author(s):  
Andrii Kovalov ◽  
◽  
Yurii Otrosh ◽  
Vitalii Tomenko ◽  
Andrii Kondratiev ◽  
...  
Keyword(s):  
Numerical Modeling ◽  
Experimental Method ◽  
Fire Resistance ◽  
Fire Retardant ◽  
Steel Structures ◽  
Resistant Steel ◽  
Standard Temperature ◽  
Steel Columns ◽  
Steel Column ◽  
Fire Resistant Steel

Purpose. Evaluation of fire resistance of fire-resistant steel structures using the developed calculation and experimental method. Methods. Finite difference method, landfill fire test method, mathematical and computer modeling of non-stationary heat exchange processes, determination of thermophysical characteristics of fire-retardant coatings based on solving direct and inverse thermal conductivity problems. Results. Geometric, physical, computer models have been developed, with the help of which the fire resistance of fire-resistant steel structures has been evaluated by the calculation-experimental method. The adequacy of the developed method for assessing the fire resistance of fire-resistant steel structures in assessing the fire resistance of fire-resistant I-beam steel column has been checked. The analysis of tests on fire resistance of fire-resistant steel columns exposed to fire at the standard temperature of the fire without the load applied to them has been carried out. A computer model of the “steel column – reactive flame retardant coating” system has been built for numerical simulation of non-stationary heating of such a system. The fire resistance of fire-resistant steel columns of I-beam section without load applied to them has been evaluated using the calculation-experimental method. Verification of results of experimental research with results of numerical modeling has been carried out. Scientific novelty. The convergence of the results of experimental data on the duration of fire exposure at the standard temperature of the fire to reach the critical temperature of steel with the results of numerical simulations has been determined. Based on the comparison of the experimental results and numerical modeling, the adequacy of the developed model to the real processes that occur when heating fire-retardant steel columns without applying a load under fire conditions at a standard fire temperature has been confirmed. The efficiency of the proposed calculation and experimental method for assessing the fire resistance of fire-resistant steel structures has been confirmed. Practical significance. It consists in the implementation of the results on objects of different purposes in assessing the fire resistance of fire-resistant steel structures by evaluating the effectiveness of fire-retardant coatings of steel building structures.

Effect of Residual Deformation of a Steel Column on its Fire Resistance under Combined Exposure "Explosion-Fire"

2019 ◽  
Vol 968 ◽  
pp. 288-293 ◽  
Author(s):  
Alexey Vasilchenko ◽  
Evgeny Doronin ◽  
Boris Ivanov ◽  
Vladimir Konoval
Keyword(s):  
Fire Resistance ◽  
Residual Deformation ◽  
Fire Retardant ◽  
Steel Structure ◽  
Steel Structures ◽  
Heating Time ◽  
Industrial Facilities ◽  
Steel Columns ◽  
Steel Column ◽  
The Stability

Calculations on the example of a steel column showed that with the combined effect of an explosion that causes deformation and subsequent fire, even without damaging the fire-retardant coat, there is a significant decrease in the fire resistance of the structure due to a decrease in the critical temperature. It is shown that, on the basis of the methodology proposed in this work, for hazardous operations industrial facilities, it is possible to predict the stability of steel columns in crash explosions followed by fire, as well as to recommend the values ​​of workloads and parameters of fire-retardant coats providing the necessary stability. It is also shown that when calculating the fire resistance limit of a steel structure with intumescent fire-retardant coat, it is necessary to take into account the proper heating time of steel structures until they lose strength.

scholarly journals EVALUATION OF FIRE RESISTANCE OF FIRE PROTECTED STEEL STRUCTURES BY CALCULATION AND EXPERIMENTAL METHOD

2021 ◽  
Vol 3 (2) ◽  
pp. 29-39
Author(s):  
A. Kovalov ◽  
◽  
Y. Otrosh ◽  
V. Tomenko ◽  
V. Slovinskyi ◽  
...  
Keyword(s):  
Experimental Method ◽  
Fire Resistance ◽  
Fire Retardant ◽  
Steel Structures ◽  
Resistant Steel ◽  
Standard Temperature ◽  
Steel Columns ◽  
Steel Column ◽  
Stationary Heating ◽  
Fire Resistant Steel

Based on the developed geometric, physical, computer and finite element model, the fire resistance of fire-resistant steel structures was evaluated by calculation and experimental method. The adequacy of the developed computational-experimental method for assessing the fire resistance of fire-resistant steel structures in assessing the fire resistance of a fire-resistant I-beam steel column was verified. The results of tests for fire resistance of steel columns with fire-retardant coating at standard temperature of the fire without the load applied to them (temperature in the furnace, temperature in certain places on the surface of fire-retardant steel columns, the behavior of the investigated fire-retardant coating). The analysis of tests on fire resistance of fire-resistant steel columns exposed to fire at standard temperature (temperature in the furnace, temperature in places of measurement of temperature on a surface of columns, behavior of a fire-retardant covering) is carried out. A computer model of the «steel column – reactive flame retardant coating» system has been built for numerical simulation of non-stationary heating of such a system. Simulation of non-stationary heating of the system «steel column – fire-retardant coating» in the software package FRIEND with the specified parameters (geometric model, thermal effects, initial and boundary conditions, properties of system materials). The reliability of the results of numerical modeling with real experimental data on the duration of fire exposure at the standard temperature of the fire to reach the critical temperature of steel. Based on the comparison of experimental results and numerical simulations, a conclusion is made about the adequacy of the developed model to the real processes that occur when heating fire-retardant steel columns without applying a load under fire conditions at standard fire temperature. The efficiency of the proposed calculation and experimental method for assessing the fire resistance of fire-resistant steel structures has been confirmed.

Определение требуемой толщины вспучивающегося огнезащитного покрытия на стальных конструкциях для заданных пределов огнестойкости

2020 ◽  
Author(s):  
Yury Shebeko ◽  
Aleksey Shebeko ◽  
Andrey Zuban
Keyword(s):  
Fire Resistance ◽  
Confidence Level ◽  
Fire Retardant ◽  
Steel Structure ◽  
Steel Structures ◽  
Mean Square ◽  
Mean Square Deviation ◽  
R Value ◽  
The Given

Проанализирована взаимосвязь разброса значений пределов огнестойкости стальных конструкций со вспучивающимися огнезащитными покрытиями и соответствующего этому разбросу интервала толщины огнезащитного покрытия. Предложена методика, на основании которой может быть осуществлен выбор необходимой толщины огнезащитного покрытия в зависимости от заданных значений дисперсии предела огнестойкости и приведенной толщины конструкции при заданной доверительной вероятности.An analysis of a relationship between fire resistance limits scatter for steel structures coated with intumescent fire retardant coating and an appropriate interval of thicknesses of the coating was carried out. A methodology for the determination of this relationship was proposed. This methodology was tested on a practical example. A steel structure with a reduced thickness of 6 mm was considered. A typical dependence of the required thickness of the structure was taken into account. A ratio of a mean square deviation of the fire resistance limit to this limit was accepted to be equal 0.1. Using these values an appropriated interval of the thicknesses of the intumescent fire retardant coating was determined. This interval can be calculated for any given confidence level. Boundaries of this interval can be not symmetric in relation to the value of the normative thickness of the fire retardant coating. The proposed methodology can be used for the determination of the required thicknesses of the intumescent fire retardant coatings on steel structures for the given r value, reduced thickness of the structure and the confidence level.

Design Study of Steel Structure Fire-Retardant Coatings under High Temperature (Fire) Conditions

2012 ◽  
Vol 594-597 ◽  
pp. 849-859
Author(s):  
Man Li Ou ◽  
Wei Jun Cao ◽  
Long Min Jiang ◽  
Hui Cao
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Fire Resistance ◽  
Fire Protection ◽  
Structural Damage ◽  
Fire Retardant ◽  
Steel Structure ◽  
Steel Structures ◽  
Strength And Stiffness ◽  
Fire Conditions

As the result of great changes occurring to mechanical properties under high temperature (fire) conditions, steel structures will soon lose the strength and stiffness and lead to structural damage. Through analysis of the steel structure fire resistance design methods under the conditions of high temperature (fire), this article explores the most used fire protection methods in steel structures—brushing or painting fire-resistant coatings, studies the fire-resistance theory of steel structure under fire conditions; in addition, the author proposes the reasonable thickness of the steel structure fire retardant coating of fire-resistant design through design examples.

scholarly journals EVALUATION OF FIRE-PROTECTIVE ABILITY OF NEWLY CREATED FIRE-PROTECTIVE COATINGS OF STEEL STRUCTURES

2021 ◽  
pp. 79-88
Author(s):  
A. Kovalov ◽  
◽  
Y. Otrosh ◽  
V. Tomenko ◽  
O. Vasylyev ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Fire Resistance ◽  
Fire Protection ◽  
Experimental Studies ◽  
Fire Retardant ◽  
Steel Structures ◽  
Steel Plates ◽  
Thermal Calculation ◽  
Thermophysical Characteristics ◽  
Standard Temperature

Abstract. The results of the development of fire-retardant substances based on domestic materials to increase the fire resistance of fire-retardant steel structures are presented. New compositions of fire-retardant substances on the basis of domestic materials capable of swelling are developed. A series of experimental studies to determine the heating temperature of fire-resistant steel structures. For this purpose, samples of reduced size in the form of a steel plate with a flame retardant applied to the heating surface were used. Fire tests of fire-retardant steel plates coated with the developed fire-retardant substance forming a coating on the protected surface, in the conditions of their tests on the standard temperature of the fire using the installation to determine the fire-retardant ability of fire-retardant coatings. The results of experimental determination of temperature from an unheated surface of steel plates with a fire-retardant covering in the conditions of fire influence at a standard temperature mode of a fire are analyzed. Based on the obtained data (temperature in the furnace and from the unheated surface of steel plates with fire protection system) the solution of the inverse problems of thermal conductivity found thermophysical characteristics of fire protection coating (thermal conductivity and specific volume), which can be used for thermal calculation heating of fire-retardant steel structures at arbitrary fire temperatures. The thermophysical characteristics of the formed fire-retardant coating are substantiated to find the characteristics of the fire-retardant ability of the newly created fire-retardant coating and to ensure the fire resistance of fire-retardant steel structures. The efficiency of the developed fire-retardant coating for protection of steel structures is proved.

Investigation of the Limit of Fire Resistance of a Steel Beam at Loss of Integrity of a Fire-Resistant Lining

2021 ◽  
Vol 1038 ◽  
pp. 345-351
Author(s):  
Oleksandr Nuianzin ◽  
Serhii Pozdieiev ◽  
Olena Borsuk ◽  
Olha Nekora
Keyword(s):  
Fire Resistance ◽  
Heating Temperature ◽  
Limit State ◽  
Fire Retardant ◽  
Mineral Wool ◽  
Steel Beam ◽  
Geometrical Parameters ◽  
Maximum Deflection ◽  
Standard Temperature ◽  
Rate Of Increase

In this article, to solve the main problems, we determined the temperature regime of heating the steel beam, which took into account the fact of loss of integrity of the fire-retardant lining due to the thermal effects of fire. When calculating the temperature, the time of exposure to the standard temperature of the fire and the value of the heating temperature of the steel beam with mineral wool lining at which the latter loses its integrity was determined. Taking into account the geometrical parameters of the cross section of the studied I-beam, according to the finite-element scheme, the steel beam was divided into four elements of SHELL type with five points of integration in thickness in the Belichko-Tsai formulation. After the calculation, the corresponding results were obtained in the form of graphs of changes in the maximum deflection of the beam and the rate of increase of the maximum deflection depending on the time of exposure to the standard temperature of the fire. The critical values of the occurrence of the limit of fire resistance according to the graph of maximum deflection and the graph of the rate of increase of deflection were determined. The difference between the indicators shows that the time of the limit state of loss of bearing capacity is 70 min less, if not taking into account the loss of fire-retardant capacity of mineral wool fire-protection due to loss of integrity.

scholarly journals Mechanical Behavior of Damaged H-Section Steel Structure

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Xibing Hu ◽  
Rui Chen ◽  
Yuxuan Xiang ◽  
Yafang Chen ◽  
Qingshan Li
Keyword(s):  
Cross Sections ◽  
Elastic Moduli ◽  
Mechanical Test ◽  
Steel Structure ◽  
Steel Structures ◽  
Computational Accuracy ◽  
Cross Sectional ◽  
Steel Columns ◽  
Steel Members ◽  
The Cross

Steel structures are usually damaged by disasters. According to the influence law of the damage on the elastic modulus of steel obtained by the mechanical test of damaged steel, the average elastic moduli of H-section steel members were analyzed. The equations for calculating the average elastic moduli of damaged H-section steel members at different damage degrees were obtained. By using the analytical cross-sectional method, the cross-sectional M-Φ-P relationships and the dimensionless parameter equations of the H-sections in the full-sectional elastic distribution, single-sided plastic distribution, and double-sided plastic distribution were derived. On the basis of the cross-sectional M-Φ-P relationships and dimensionless parameters of actual steel members, the approximate calculation equations for the damaged cross sections were obtained. The Newmark method was used to analyze the deformation of damaged steel columns. Analytical results show good agreement with the test results. The equations and methods proposed in this study have high computational accuracy, and these can be applied to the cross-sectional M-Φ-P relationships and deformation calculation of damaged steel members.

Research on Fire Resistance Performance of Pre-Stressed Suspended Steel Reticulated Shell

2010 ◽  
Vol 163-167 ◽  
pp. 790-794
Author(s):  
Feng Bo Yu ◽  
Xin Tang Wang ◽  
Ming Zhou ◽  
Wan Zhen Wang
Keyword(s):  
High Temperature ◽  
Fire Resistance ◽  
Steel Structure ◽  
Steel Structures ◽  
Space Structure ◽  
International Standards ◽  
Large Space ◽  
Finite Element Software ◽  
Large Space Structure ◽  
Fire Scene

Pre-stressed steel structures with large space are widely used in stadium, exhibition hall, theater and other buildings today. In order to study the fire-resistance behavior of suspended steel lattice shell of a stadium, the method of performance-based fire resistance design is used. First of all, the stadium physical model is established and the software FDS is used to determine the heating curves of the measuring points of the large space structure for two fire scenes. Compared with international standards heating curve, the heating curves of the large space structure obtained here has characteristic of local high-temperature. The finite element software MSC.MARC is further used to simulate the fire behavior of the pre-stressed steel structure with large space, in which the fire scene with 10MW design power of fire source and 30 minutes duration of fire are considered and two loading ways that overall non-uniform temperature field loading and the local high temperature components loading are accepted. The results show that the pre-stressed steel structure with large space has good fire resistance behavior, and the overall failure will not take place for the fire scene suggested here during 30 minutes duration of fire.

Influence of the Fire Temperature Regime on the Fire-Retardant Ability of Reinforced-Concrete Floors Coating

2020 ◽  
Vol 1006 ◽  
pp. 87-92
Author(s):  
Andrii Kovalov ◽  
Yurii Otrosh ◽  
Oleg Semkiv ◽  
Volodymyr Konoval ◽  
Oleksandr Chernenko
Keyword(s):  
Reinforced Concrete ◽  
Fire Resistance ◽  
Temperature Regime ◽  
Fire Retardant ◽  
Protective Layer ◽  
Fire Regimes ◽  
Hollow Core ◽  
Standard Temperature ◽  
Concrete Floor

In the paper, the tests have been analysed for fire-resistant quality of the hollow-core reinforced-concrete floors with fire-retardant plaster covering under standard temperature regime of the fire. Using the methodology for determining the characteristics of fire-retardant coatings ability for reinforced-concrete floors, the dependences have been obtained of the fire-retardant coating thickness from the concrete protective layer of a hollow-core reinforced-concrete floor for a fire resistance limit of 180 minutes with a temperature regime of hydrocarbon fire and a tunnel curve according to the Netherlands standards (RWS). It has been concluded about the minimum required thickness of the studied fire-retardant coating to provide the required fire resistance limit of a hollow-core reinforced-concrete floor under the indicated fire regimes.

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