VERIFICATION RESULTS OF THE PRESENTATION OF THE PROTECTION OF THE UNSTEADING TEMPERATURE FIELD AT THE CONCRETE CONSTRUCTION FOR THE MIND OF THESTANDARD TEMPERATURE REFRIGERATION FIRE

The main classification indicator, in terms of fire safety, is the degree of fire resistance of the house. Depending on this indicator normalize its surface, the area of development and distance to other buildings and structures. The degree of fire resistance of the house is determined by the limit of fire resistance of its building structures and the limit of the fire spread by these structures. Therefore, the value of the fire resistance limit of building constructions, which consists of a house, significantly affect its architectural solution and the parameters of construction in general. On this basis, taking into account the approaches to ensuring normalized fire resistance limits of the design and the features of their behavior under high-temperature (fire) influence is very relevant. Most research on building constructions is based on two methods of determining the limit of fire resistance - experimental and analytical. The first one is to determine the limit of fire resistance on the basis of experimental research, and the second one is based on methods of analytical or computational and experimental research. In most countries, the experimental determination of fire resistance of building structures is carried out by means of fire tests. However, experimental studies require significant financial costs and high accuracy of fire tests. The alternative methods for assessing the fire resistance of building elements on the basis of field fire tests are the design methods used for the design of fire-resistant building constructions. In the article, the verification of the results of analytical studies on the propagation of the non-stationary temperature field in the concrete structure under the conditions of the influence of the standard temperature regime of the fire in comparison with the results of field fire tests has been carried out. The analysis of the obtained results shows that the results of the calculation of the distribution of the non-stationary temperature field in the thickness of the concrete structure without coating and with the applied flame retardant coating of the Phoenix STV, manufactured by the company "A + B Ukraine" on the front of the Phoenix Contact, obtained using mathematical models, are qualitatively and quantitatively convergent with results obtained experimentally. The difference between the theoretical and experimental data for a concrete structure without coating is 4%, and with the applied fire-retardant coating does not exceed 10%.

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METHOD OF EVALUATION OF THE FIRE RESISTANCE OF COMPOSITE BUILDING STRUCTURES

URBAN CONSTRUCTION AND ARCHITECTURE ◽

10.17673/vestnik.2018.03.3 ◽

2018 ◽

Vol 8 (3) ◽

pp. 12-17

Author(s):

Denis A. PANFILOV ◽

Nikolay A. ILYIN ◽

Yury V. ZHILTSOV ◽

Ekaterina V. BLINKOVA

Keyword(s):

Reinforced Concrete ◽

Fire Resistance ◽

Concrete Structure ◽

Building Structures ◽

Reinforced Concrete Structure ◽

Resource Saving ◽

Concrete Building ◽

Innovative Solution ◽

Method Of Evaluation ◽

Building Practice

The article describes a new method for determining the design fi re resistance of composite (steel-concrete) building constructions of buildings. The advanced algorithm of the decision of the fi re-technical task in the part of express calculation of design fi re resistance of composite building constructions is given. A new constructive form of composite reinforced concrete structure of the building has been developed and the system of actions for assessing the fi re resistance of its elements at the level of inventions, which are implemented in building practice, has been improved. The components of the creative result of scientifi c work and the content of the technical eff ect, including resource saving, are introduced, with the introduction of an innovative solution in the practice of fi re protection and providing fi re resistance of perspective building constructions of buildings.

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Increase of Temperature and Fire Resistance for Reinforced-Concrete Structures by Surface Treatment with Protective Coating

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.788.36 ◽

2018 ◽

Vol 788 ◽

pp. 36-44

Author(s):

Liudmyla Demydchuk ◽

Dmytro Sapozhnyk

Keyword(s):

Reinforced Concrete ◽

Fire Resistance ◽

Protective Coating ◽

Concrete Structures ◽

Fire Retardant ◽

Reinforced Concrete Structures ◽

Building Structures ◽

Fire Tests ◽

Normative Documents ◽

Concrete Building

The normative documents of Ukraine (DBN V.1.1.7 ̶ 2016) [1] establish that the limit of fire resistance of reinforced-concrete building structures is determined by the calculation method or by fire tests, and shall be at least 45 minutes. Taking into account the modern construction technologies, namely, the reduction of the section of the main building reinforced-concrete structures, it is expedient to use fire-retardant coatings to provide the necessary fire resistance limit.

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Screen Wall Fire Resistance Investigation

Frontiers in Built Environment ◽

10.3389/fbuil.2020.607305 ◽

2021 ◽

Vol 6 ◽

Author(s):

Tatiana Eremina ◽

Dmitry Korolchenko ◽

V. E. Fadeev

Keyword(s):

Fire Resistance ◽

Functional Dependence ◽

Heat Exposure ◽

Experimental Studies ◽

Engineering Problem ◽

Thermal Engineering ◽

Wall Structure ◽

Building Structures ◽

Critical Temperatures ◽

Fire Conditions

The assessment of fire resistance for building constructions has been carried out by the solution of the heat engineering problem for heating up building structures under the conditions of non-stationary heat exposure with standard fire conditions. The finite element method is used as the solution method. Numerical simulation of heating of considered building structures under fire conditions was carried out using the Ansys Mechanical computer complex, which allows for a thermal engineering design to be calculated on the basis of its software model. The resulting functional dependence allows for determining the actual fire resistance of Pf depending on the thickness of sheets δ of the outer skin made of the basalt fire-proof material, as well as the geometric parameters of the protective screen (δ) depending on the required fire resistance from the condition of compliance with the requirements of constructive fire safety (Pf > Preq). Experimental studies to determine the fire resistance for membrane wall structures showed that an increase in temperature on its unheated surface vs. structure temperature prior to testing more than 180° С (195°С) occurs not earlier than 31 min. Upon reaching the critical temperatures on the unheated surface of the membrane wall structure independing on its thickness, the fire resistance limits REI 30-REI 120 are reached.

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DETERMINATION OF NON-STATIONARY TEMPERATURE FIELD IN THE SYSTEM OF TWO SPHERICAL SHELL

Bulletin of Lviv State University of Life Safety ◽

10.32447/20784643.19.2019.08 ◽

2019 ◽

Vol 19 ◽

pp. 79-86

Author(s):

R. Tatsii ◽

O. Pazen

Keyword(s):

Boundary Condition ◽

Temperature Field ◽

Temperature Change ◽

Fire Resistance ◽

Outer Surface ◽

Original Problem ◽

Auxiliary Problem ◽

Technical Problem ◽

Small Radius ◽

Stationary Temperature Field

The main classification indicator, in terms of fire safety, is the degree of fire resistance of the house. Depending on this indicator normalize its surface, the area of development and distance to other buildings and structures. The de-gree of fire resistance of the house is determined by the limit of fire resistance of its building structures and the limit of the fire spread by these structures. Therefore, the value of the fire resistance limit of building constructions, which con-sists of a house, significantly affect its architectural solution and the parameters of construction in general. On this ba-sis, taking into account the approaches to ensuring normalized fire resistance limits of the design and the features of their behavior under high-temperature (fire) influence is very relevant.Most research on building constructions. The proposed work is devoted to the application of the direct method to the study of heat transfer processes in the system of two embedded spherical bodies – a ball in a sphere. It is assumed that there is an ideal thermal contact between the balls, and the law of temperature change on the outer surface is an arbitrary function of time, and evenly distributed over the surface of the ball. Consequently, isotherms inside this construction are concentric fields, that is, the problem is symmetric and is solved for the first time in such a statement. To solve such a problem, in parallel, the auxil-iary problem of determining the distribution of a non-stationary temperature field in a two-layer hollow spherical structure with a "extracted" sphere of sufficiently small radius is raised. In this case the symmetry condition of the original problem is replaced by the condition of the second kind on the inner surface of this construction. The implementation of the solution of the auxiliary problem is carried out by applying a reduction method using the concept of quasiderivatives. In the future, the Fourier scheme is used with the use of the modified eigenfunctions method. To find the solution of the original problem, the idea of the boundary transition is used by passing the radius of the withdrawn bullet to zero. It is established that in this approach all the eigenfunctions of the corresponding problem on the eigenvalues have no singularities at zero, which means that the solutions of the original problem are constrained throughout the design. The solution of this problem at zero temperature on the outer surface coincides with those known in the literature. To illustrate the proposed method, a model example of finding the temperature field distribution in a system of two spherical bodies with different thermophysical properties of materials is solved. The results of the calcu-lations are presented in the form of a table and a three-dimensional graph of temperature change, depending on the time and spatial coordinates. The generalization of the results obtained in the event of any finite number of nested balls is a purely technical problem, and not a fundamental one. Note that while changing the boundary condition of the first kind to any other boundary condition (for example, the third kind) does not affect the scheme of solving similar tasks. Since the general scheme of studying the distribution of temperature fields in multi-layered structures with an arbitrary number of layers in the presence of internal sources of heat is studied in detail, the setting and solving of such problems for the system of nested balls does not cause any difficulty.

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Experimental estimation of the temperature regime of the model reservoir with a protective wall type "glass in glass" under fire conditions

Technology of technosphere safety ◽

10.25257/tts.2020.4.90.32-48 ◽

2020 ◽

Vol 90 ◽

pp. 32-48

Author(s):

D. N. Rubtsov ◽

◽

A. N. Egorov ◽

Keyword(s):

Temperature Measurement ◽

Experimental Research ◽

Thermal State ◽

Experimental Studies ◽

Heating Time ◽

The Body ◽

Steel Shell ◽

Contact Method ◽

Fire Tests ◽

Wall Model

Introduction. The publication contains a description and results of a series of fire tests of a model of a "glass in a glass" oil product tank, obtained inter alia using the method of contact temperature measurement. The paper presents the formulation of the problem of experimental research, the conditions and methods for their implementation, a description of the instrumental base and the results obtained. The aims and goals. An experimental study is carried out to assess the effect of heat loads of a fire on the body of the protective wall in the event of a fire in the main tank as well as for further use of the obtained empirical dependences of the temperature of the body of the protective wall on the heating time for carrying out the verification procedure of the mathematical model for its adequacy to the investigated physical process. Methodology. Experimental research method, contact method of temperature measurement, observation, analysis, generalization. The results of the study. The paper presents the results of experimental studies on the basis of which empirical dependences were obtained for calculating the change in the temperature values of the protective wall model depending on the time of its heating. Fire tests made it possible to establish the general thermal state of the "main reservoir with oil product – protective wall" system. The contribution of the influence of different speeds of wind flows on the heating of the protective wall of the reservoir is determined. Conclusion. The data obtained in the experiments will be used for the numerical assessment of the stress-strain state of the steel shell of the tank protective wall in case of fire in the main tank, which is necessary for the design of fire-fighting systems for water sprinkling and foam fire extinguishing on the protective wall of the tank of the "glass in glass" type. Key words: protective wall, model, oil product, fire tests, fire, tank, stand, thermocouple, experiment.

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Experimental and Computer Researches of Ferroconcrete Beams at High-Temperature Influences

Materials Science Forum ◽

10.4028/www.scientific.net/msf.968.355 ◽

2019 ◽

Vol 968 ◽

pp. 355-360 ◽

Cited By ~ 5

Author(s):

Yuriy Otrosh ◽

Mykola Surianinov ◽

Alexander Golodnov ◽

Olena Starova

Keyword(s):

Computer Simulation ◽

High Temperature ◽

Numerical Analysis ◽

Experimental Research ◽

Experimental Studies ◽

Research Data ◽

Fire Tests ◽

Practical Application ◽

Software Complex

The paper presents experimental and computer researches of ferroconcrete beams at high-temperature influences. There were conducted the experimental fire tests of ferroconcrete beams. The most promising way of verifying these experimental research data is computer simulation of structures, also during a fire. In order to evaluate the quality of the experiment and the reliability of the received temperature distribution, there was conducted a computer simulation of the ferroconcrete beam in the ANSYS R.17.1 software complex. There were conducted a comparative analysis of the results of experimental studies and numerical analysis. The results confirm that the method of conducted experimental research and computer simulation with further numerical analysis can be recommended for practical application.

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DEVELOPMENT OF FIRE-PROTECTIVE PLASTER SURFACES COMPOSITES AND DESIGN METHOD FOR DETERMINING THE FIRE RESISTANCE OF TWO-LAYER ARMOCEMENT ELEMENTS

Вестник ГГНТУ. Технические науки ◽

10.34708/gstou.2019.15.1.007 ◽

2019 ◽

Author(s):

Т.А. Хежев

Keyword(s):

Fire Resistance ◽

Design Method ◽

Experimental Studies ◽

Engineering Calculation ◽

Building Structures ◽

Resource Base ◽

Heat Engineering ◽

Flame Retardant Properties ◽

Increased Strength ◽

Acceptable Agreement

Приведены результаты исследований составов гипсоизвестковоцементовермикулитотуфобетонных композитов. Расширение сырьевой базы, повышение прочности и огнезащитных свойств, а также снижение стоимости композита решается за счет использования в сырьевой смеси отходов пиления вулканического туфа. Приведены результаты экспериментальных исследований огнестойкости двухслойных армоцементных элементов. Разработан алгоритм теплотехнического расчета предела огнестойкости многослойных строительных конструкций, обеспечивающий приемлемое совпадение расчетных значений с экспериментальными данными. Разработано программное обеспечение теплотехнического расчета предела огнестойкости армоцементных конструкций с огнезащитным слоем из гипсовермикулитобетона, получены выражения для коэффициентов теплопроводности и теплоемкости разработанных композитов. The results of studies of gypsumlimestone cementvermiculite and concrete composites are given. Expanded resource base, increased strength and flame retardant properties, as well as reduced cost of the composite. using volcanic tuff in the raw mix. The results of experimental studies of the fire resistance of twolayer cementcontaining elements are given. An algorithm for heat engineering calculation of the fire resistance limit of multilayer building structures has been developed, which ensures acceptable agreement between the calculated values and experimental data. The software for the heat engineering calculation of the fire resistance limit of cementcement constructions with a fireproof layer made of gypsum vermiculite concrete has been developed, expressions for the thermal conductivity and heat capacity of the developed composites have been obtained.

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Assessment of the volume activity of α-radioactive wastes on surface and specific contamination by portable γ-spectrometry method

Russian Journal of Occupational Health and Industrial Ecology ◽

10.31089/1026-9428-2020-60-7-468-473 ◽

2020 ◽

pp. 468-473

Author(s):

I. P. Korenkov ◽

A. I. Ermakov ◽

A. B. Mayzik ◽

T. N. Laschenova ◽

V. N. Klochkov ◽

...

Keyword(s):

Specific Activity ◽

Experimental Studies ◽

Germanium Detector ◽

Low Energy ◽

Gamma Ray Spectrometry ◽

Building Structures ◽

Germanium Detectors ◽

Volume Activity ◽

Β Decay ◽

Γ Spectrometry

The aim of the study is to evaluate the volume activity of radioactive waste (RW) by surface and specific alpha contamination using portable gamma-spectrometry.Materials and methods. Methods of rapid assessment of the content of α-emitting radionuclides in solid waste of various morphologies using gamma-spectrometers based on germanium detectors are considered. Computational methods for determining the effectiveness of radionuclide registration are presented.Results. The possibility of using portable gamma-ray spectrometry to assess the surface and specific activity of various materials contaminated with α-emitters (232Th, 235U, 238U, 237Np, 239Pu, 240Pu and 241Am) is shown. The calculated values of the registration efficiency of low-energy gamma-emitters obtained by modeling the spatial-energy parameters of the detector are given.To simplify the solution of this problem, the calculation program used 20 standard templates of various geometries (rectangular, cylindrical, conical, spherical, etc.). The main sources of error in the survey of contaminated surfaces, largesized equipment and building structures were investigated.Conclusions. The possibilities of portable γ-spectrometry for estimating the volume of RW based on the surface density of contamination of materials with radionuclides of uranium and transuranic elements are investigated. When using γ-spectrometer with a high-purity germanium detector with a range of γ-quanta extended in the low-energy region, radionuclides such as 232Th, 235U,238U, 237Np, 241Am were determined by their own radiation or by the radiation of their daughter products.The “problem” element is plutonium, for rapid evaluation of which it is proposed, in accordance with the radionuclide vector methodology, to use 241Am, which accumulates during the β-decay of 241Pu.According to calculations, the most likely value of the activity ratio 239Pu/241Am for the object where the work was performed (scaling factor) varies in the range from 5.0 to 9.0.Based on the results of calculations and experimental studies, the parameters of the efficiency of registration of various α-emitting radionuclides by portable γ-spectrometers. It has been found that for germanium detectors with an absolute efficiency of registering a point source of 7÷15%, it is n×10–5÷n×10–4%.

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Experimental research control methods of the spatial position of building constructions

Geodesy and Cartography ◽

10.22389/0016-7126-2017-922-4-7-12 ◽

2017 ◽

Vol 922 (4) ◽

pp. 7-12 ◽

Cited By ~ 2

Author(s):

G.A. Shekhovtsov ◽

R.P. Shekhovtsova ◽

D.P. Ivenin ◽

O.V. Raskatkina

Keyword(s):

Simultaneous Determination ◽

Experimental Research ◽

Vertical Plane ◽

Error Theory ◽

Spatial Position ◽

Bridge Crane ◽

Building Structures ◽

Control Methods ◽

Engineering Geodesy

The article contains the method of discrete scanning points in the vertical plane of the columns and roof trusses for the simultaneous determination of vertical columns, the distance between them in flight at their tip and deflection farms with one point standing and only one performer. The technique is based on the use of reflectorless electronic tachymeter and its SDh key. Experimental research of methods on the elements of building structures NNGASU educational housing using electronic tachymeter SET530R. Results of the experiments were monitored by a coordinate and photographic methods, as well as with the developed at the chair of Engineering Geodesy laser-mirroring device designed to measure inaccessible or hard to reach distances. Analysis methods of error theory position and the results of its comparison with other methods have shown that it provides the required accuracy, easy to perform, does not require the output of the observer on the crane path or lift to the towers, free from the multiple engagement of the bridge crane and can be successfully applied on practice.

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