Journal of Civil Protection

Scientifically based conception for integrated assessing the fire resistance of modern building structures

Ivan I. Palevoda — Fri, 10 May 2024 00:00:00 +0300

Purpose. To systematize the approaches to determining fire resistance limits and develop a scientifically based concept for a comprehensive assessment of fire resistance of modern building structures made of concrete, covering three levels of detail: expert assessment, optimizing calculation, justification of new solutions.

Methods. Analysis and generalization of the results of theoretical and experimental research.

Findings. A scientifically based conception for integrated assessing the fire resistance of modern building structures has been developed, based on the conceptual development of approaches related to modeling the operation of structures in case of fire, which makes it possible to ensure the fire safety of buildings and reduce the economic risk of fire by increasing the share of prevented losses.

Application field of research. The obtained research results can be used in developing standards for the design and construction of building structures made of concrete, for solving problems of assessing fire resistance in the design and construction of buildings and structures, as well as while selecting effective solutions for structural fire protection.

Pre-combustion thermal properties of combustible extruded polystyrene obtained by high temperature heating

Vadim A. Kudryashov, Yuriy P. Ivlev, Anton S. Drobysh, Sergey S. Botyan — Fri, 10 May 2024 00:00:00 +0300

Purpose. Based on experimental data and theoretical research, to assess the pre-combustion thermal properties of combustible extruded polystyrene insulation obtained by high-temperature heating and their influence on the fire resistance and fire hazard class of structures with profiled sheet roofing.

Methods. Detailed examination of the behavior of combustible extruded polystyrene under elevated temperature conditions was conducted through testing of model samples using equipment for assessing flammability and determining flash point in an open crucible TVO-LAB-01 with an expanded base of measuring instruments.

Findings. Model test results indicate that identical thermal damage is characteristic for samples from different manufacturers, acquired after surface temperature increases above 100 °C, with the formation of accumulations (clusters) of quasi-molten (damaged) material on the heated surface at temperatures around 120…140° C. As the temperature approaches to 160 °C, the damage becomes more pronounced, corresponding to melting. If the thermal power is insufficient to form a melt throughout the material volume, its shrinkage occurs until the temperature decreases along the axis of the heat flow to the melt temperature (120…140 °C). To assess thermal damage in large-scale tests, it is advisable to compare the damage to extruded polystyrene with Table 2 of this article, considering temperature measurement data. The fact of burning of extruded polystyrene can only be confirmed by the presence of foamed residue indicating boiling of the melt. To model the thermal damage of extruded polystyrene in the form of thermal shrinkage it is advisable to use a critical temperature which does not exceed 100 °C.

Application field of research. The research results can be applied in the design and construction of structures with profiled sheet roofing using a combined approach to determine the required amount of combustible and non-combustible insulation, combustible roofing material, and vapor barrier.

The influence of foaming agent concentration on the wetting ability and foam expansion rate when dosing in automatic sprinkler systems

Fri, 10 May 2024 00:00:00 +0300

Purpose. To determine the dependence of the wetting ability and expansion ratio of foam on the concentration of the foaming agent (wetting agent) for extinguishing fires, and also establish the concentration limits of the foaming agent at which the fire extinguishing solution meets the requirements of technical regulations and technical documentation of the manufacturer for the expansion ratio of foam and the wetting ability indicator. Using the example of a model room, to perform a hydraulic calculation of an automatic fire extinguishing sprinkler installation and analyze the possibility of maintaining the required concentration of foam concentrate using a pressure-type dosing device with a washer.

Methods. The general methodology of the work included the theoretical (analysis, synthesis, comparison) and experimental research methods. Wetting ability of the foaming solution and the expansion rate of generated foam were determined experimentally using the test method described in STB 2459-2016. Processing of experimental data was performed using regression analysis, as well as establishing the uncertainty of measurements.

Findings. In the result of experimental studies, it was found that the concentration of foaming agents (wetting agents) OPS-0,4 by more than 0.67 % and SP-01 by more than 0.77 % in the extinguishing solution can lead to an increase in the expansion rate of foam formed at the outlet of the automatic fire sprinkler system by more than 5, and consequently, cause the deterioration of the effectiveness of the fire extinguishing. For this reason, in sprinkler fire extinguishing system (FES), the dosing device must provide a certain minimum (operation of one dictating sprinkler) and maximum flow rate of the foam agent to maintain a concentration sufficient for effective extinguishing. Using the example of a model room measuring 12.5×7.7 m, it is shown that when using a pressure-type dosing device with a washer having a fixed hole diameter for introducing the foam agent into the supply pipeline of the unit, an excess of the concentration of foaming agent SP-01 brand recommended by manufacturers by more than 7.7 times occurs when opening three of the twenty-four sprinklers of the ceiling section of the FES. Based on this, it is necessary to conclude that when designing sprinkler FES, it is necessary to carry out a detailed calculation of the dosing of the foaming agent when the sprinklers are sequentially activated in the section, or to use dosing devices capable of automatically adjusting the dosing depending on the water flow in the supply pipeline.

Application field of research. Designing of automatic FES using sprinklers.

Electronic assistant to the chief of fire staff

Vyacheslav V. Lakhvich, Anton V. Sivuda — Fri, 10 May 2024 00:00:00 +0300

Purpose. Experimental determination of the time spent on information collection and subsequent decision-making by the chief of staff at the fire at auditory and visual acquisition of information; development of an electronic assistant to the chief of staff at the fire for the collection, processing, transmission and visualization of data on fire tankers.

Methods. Theoretical analysis, modeling.

Findings. The advantages of obtaining and processing data in the form of visualized graphic information in comparison with auditory acquisition of the same information about the work of units on fire tankers during emergency response are substantiated. At visual reception visual information gathering not only reduces time for information gathering in comparison with auditory (approximately in 8 times), but also allows to make decisions on the basis of the collected data faster (by 27 %). A prototype of a hardware-software module for collection, processing, transmission and visualization of fire tanker parameters, such as the volume of water in the tank, the volume of foaming agent, power take-off, power supply voltage in the on-board electric circuit of the vehicle, geopositioning of the vehicle, has been developed.

Application field of research. Extinguishing fires and eliminating emergency situations, which involve a significant amount of equipment.

3D-modeling and the research of the stress state of modern 5 m³ tank’s construction of fire trucks made of composite materials and high-alloy steel

Sergey G. Korotkevich, Vadim A. Kovtun, Pavel V. Kovalev — Fri, 10 May 2024 00:00:00 +0300

Purpose. Calculation of the stress state and safety margin of modern 5 m³ tank’s construction of fire trucks made of composite materials and high-alloy steel considering operational loads.

Methods. The development of 3D-models of tank structures was carried out using the SolidWorks software package. The creation of their finite element models and calculations were carried out in the Static Stractural module of the ANSYS Workbench software package.

Findings. The analysis of the composite materials’ features utilization in the modern production of fire trucks is carried out. Their advantages in comparison with steel ones are presented. 3D finite element models of 5 m³ tank structures made of reinforced fibrous fiberglass and high-alloy stainless steel have been developed. To carry out a comparative calculation, the most loaded modes and conditions characterizing the features of the movement of fire trucks moving to emergency response place were selected. The calculation made it possible to establish dependencies linking the stressed state of tank structures with the modes of movement of fire trucks, as well as to identify the most loaded nodes in the structures. The results of calculating the safety margin of tank structures considering operational loads are presented.

Application field of research. Firefighting rescue units, industrial enterprises and higher educational institutions.

Change of coal’s gas content during transportation to the temporary storage

Semyon G. Gendler, Anastasiia Yu. Stepantsova, Dmitriy B. Mozzhanov — Fri, 10 May 2024 00:00:00 +0300

Purpose. Definition of correlation between residual gas content in coal stored in closed temporary storages and coal’s natural gas content, which depends on the weather, train’s transportation time and the amount of air ventilating closed storage needed to maintain methane concentration below threshold limit value.

Methods. Analysis of the transportation process from excavation site to the temporary storages, which takes into account transportation duration, carriages type and atmospheric temperature; experimental determination of effective diffusion coefficient for methane in coal fragments; theoretical research of thermal pattern dynamic for coal mass in train carriages; computational analysis of coal’s gas content dynamic during transportation and correlation between residual coal’s gas content and required airflow rate for temporary storage ventilation.

Findings. This paper represents the results of research of change of coal’s gas content during excavation, transportation to the surface and further transportation to temporary storages by train by evaluating influence of physical and chemical properties of coal, effective diffusion coefficient in particular, and mean atmospheric temperature. According to procured data, value of effective diffusion coefficient, which depends on coal transportation time and its mean particle diameter, increases with the rise of mean coal mass temperature. Calculation of mean coal mass temperature per unit of volume during transportation is based on approximate method of Bubnov – Galerkin. Residual coal’s gas content after transportation is calculated as difference between value of coal’s gas content after loading into carriages and coal’s gas content after delivery to temporary storages. Correlation between residual coal’s gas content and required airflow rate for temporary storage ventilation has been established.

Application field of research. The results of the study can be used to ensure methane safety during temporary storage of coal raw materials in closed warehouses.

Development of an updated National strategy of reducing the risk of emergencies in the Republic of Belarus until 2030

Sergey A. Salanovich, Ivan I. Palevoda, Maxim M. Tikhonov, Nikolay M. Olesiyuk — Fri, 10 May 2024 00:00:00 +0300

Purpose. Updating the existing National strategy to reduce the risk of emergency situations occurring in the Republic of Belarus for 2019–2030.

Methods. General scientific methods of research: analysis and synthesis, comparison and generalization.

Findings. The updated National strategy of reducing the risk of emergencies in the Republic of Belarus until 2030 was developed.

Application field of research. The results of the work can be used in practice in strategic planning of realization of measures to reduce the risk of emergencies.

Methodology of risk assessment of natural and technogenic emergencies

Dmitry S. Mikanovich, Artem A. Morozov, Andrey I. Gnitsevich, Anton S. Gusev — Fri, 10 May 2024 00:00:00 +0300

Purpose. To formulate the main provisions of the methodology of risk assessment of natural and man-made emergencies (hereinafter – ES).

Methods. The method of theoretical analysis of literary sources was used to study the regulatory framework for emergency risk assessment in various countries. The obtained results were processed using the estimation method and theoretical generalization of the obtained data.

Findings. The main provisions of the methodology of ES risk assessment, which establish the uniformity of approaches to the analysis and assessment of ES risks based on the principles of multilateral participation and assistance of stakeholders, have been determined.

Application field of research. The results of the research can be used by the Ministry of Emergency Situations in the development of the methodology of ES risk assessment.

Ritual and tradition as a means of transmission firefighter-rescuers’ corporate culture

Tatyana G. Kovaleva, Tatyana G. Dement'eva, Lyubov N. Luts — Fri, 10 May 2024 00:00:00 +0300

Purpose. To reveal the importance of traditions and rituals in the development of the corporate culture of the fire and rescue service. To describe the historical, moral and ethical aspects of the traditions and rituals of Belarusian firefighters. To show the practical and pragmatic significance of preserving and transmitting traditions and rituals from generation to generation as a factor in the patriotic, moral and ethical education of a rescuer.

Methods. Critical analysis of theoretical sources on the semiotics of culture, describing sign systems with a specific relationship between form and content. Sociolinguistic analysis of existing traditions and rituals of rescuers. Interviewing employees of bodies and departments of the Ministry of Emergency Situations.

Findings. The educational potential has been revealed and the effectiveness of the influence of traditions and rituals as psychological, cultural, historical and patriotic education of firefighters and rescuers, as well as an element of professional identification and familiarization with corporate culture, has been proven.

Application field of research. The educational space of modern institutions that train fire rescuers. The sphere of patriotic and ideological education, as well as socio-cultural education of young rescue firefighters.

Information conceptual model of professional activity of officials of state fire supervision when implementing supervision and prevention measures (based on the example of organizing monitoring)

Andrey V. Surikov, Natal'ya V. Zaynudinova, Stepan A. Barysh — Fri, 10 May 2024 00:00:00 +0300

Purpose. To develop an information conceptual model of the professional activities of officials of state fire supervision authorities while implementing supervisory and preventive measures (using the example of organizing monitoring).

Methods. The general methodology of the work included the use of theoretical research methods (analysis and synthesis).

Findings. An analysis of regulatory legal acts regulating control (supervisory) activities in the Republic of Belarus was carried out in relation to the activities of officials of state fire supervision authorities. An information conceptual model of the professional activities of these officials during monitoring is presented.

Application field of research. The obtained research results can be applied in educational process in the training of employees of state fire supervision authorities, as well as in the development of simulation training systems for conducting supervisory and preventive measures using this form of state control (supervision).