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Kolesnikov A.

Candidate of Engineering sciences (PhD), Associate Professor, South-Kazakhstan University named after M. Auezov, Department of Life safety and environmental protection

Study of thermal-physical properties of porous ceramic insulation products

https://doi.org/10.58224/2618-7183-2025-8-3-7
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Abstract
The detailed description of the main parameters, influencing the thermal insulation characteristics of building walls is presented in this article. In addition the analysis of this parameters study in modern construction practice is made. The main characteristics of concrete based on porous expanded clay granules are presented, including the results of studies of capillary absorption, moisture transfer rate and moisture absorption properties of porous expanded clay concrete samples affecting the thermal conductivity coefficient. The research results are presented in the context of thermal insulation and fire-resistant ceramic granules application as fillers in porous concrete walls. On the basis of results of study of the organomineral additives influence on the thermal conductivity coefficient of porous expanded clay concrete the study of porous expanded clay concrete samples were carried out. The porous and dense wall concrete sorption moisture and vapour permeability are determined in laboratory conditions. Also the main changes of these parameters at different values of relative humidity of surrounding air are determined.
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The challenges of reusing thermal power plant wastes to produce cellular concrete modified with wollastonite

https://doi.org/10.58224/2618-7183-2025-8-3-10
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Abstract
This paper presents new approaches of reusing fly ash generated in thermal power plant in the manufacturing of cellular concrete. Therefore, the research novelty is to make a meaningful utilization of fly ash as a binder to improve cellular concrete properties. The study has showed that fly ash has pozzolana properties which can boost up mechanical strength, thermal insulation and durability of cellular concrete, which may lead to obtain high quality final product in comparison with traditional building materials. Moreover, utilization of fly ash facilitates both reduction of heat conductivity and reduction of concrete density. This properties make cellular concrete resistant to heat transfer. Physical, mechanical and thermal tests have been carried out during research. The study of type of dependence between cellular concrete durability and its mix design has a valuable practical importance since it supports to reach maximum durability in lightly consumption of binder. We may conclude that the utilization of fly ash in the amount of 295 kg/m3, while the cellular concrete density is equal to 600 kg/m3, allows to solve a number of problems such as damaging of human health and environment pollution and to develop energy efficient cellular concrete. The research included the results of cellular concrete mix flowability, density, moisture, strength properties and concrete grade equal to B2,5-B3,5 with a density of porous ash concrete equal to 600 kg/m³. The natural wollastonite was utilized in this research as a reinforcing material to improve the tensile stregnth of cellular concrete.
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Capabilities of existing frame buildings with shear diaphragms to resist seismic effects of destructive earthquakes

https://doi.org/10.58224/2618-7183-2025-8-2-10
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Abstract
In recent times, numerous powerful earthquakes have struck across the globe, with intensities exceeding standard design values by 1 … 2 points, resulting in widespread destruction of buildings and infrastructure. These events underscore the urgent need to revise current regulatory frameworks, particularly by increasing the prescribed seismic design loads. Consequently, it becomes essential to reassess the seismic performance of existing buildings that were originally designed according to outdated codes. This article explores the critical issue of evaluating and enhancing the earthquake resilience of such structures in light of evolving seismic realities.This article presents the results of a seismic resistance assessment for a nine-story reinforced concrete frame building with stiffening diaphragms, subjected to seismic loads exceeding the original design values. To evaluate the seismic performance of the existing structure, a numerical analysis was carried out using a static nonlinear (pushover) method. As a failure criterion, the maximum seismic load corresponding to the complete loss of the building’s load-bearing capacity was selected. The seismic resistance was assessed by considering the maximum values of seismic impact from two horizontal components, applied independently along each principal direction of the building. According to the adopted methodology, the structural model of the building frame, subjected to vertical loads, was incrementally loaded with the horizontal component of seismic action using displacement-controlled nonlinear static analysis. The horizontal load was gradually increased until the structure reached its maximum seismic capacity. The building under study was originally designed in accordance with the outdated seismic code SNiP RK 2.03-30-2006, which specified a seismic load corresponding to a site acceleration of 0.125g. However, under current seismic design standards—SP RK 2.03-30-2017*—the same site is classified for a seismic acceleration of 0.2g. Therefore, the existing structure is now expected to resist a seismic load that is 1.6 times greater than the load considered in its original design (0.2g vs. 0.125g). The study revealed that complete loss of the building's load-bearing capacity occurs under a special load combination when the seismic load is applied in the direction of the Y-axis. It was determined that structural failure takes place at the thirteenth loading stage, corresponding to a horizontal seismic acceleration of 0.163g. This value is lower than the required acceleration of 0.2g as specified by the current seismic code SP RK 2.03-30-2017*. This finding indicates that the building is incapable of withstanding the seismic demands outlined in the updated standards, highlighting its insufficient seismic resistance under the revised design requirements. Based on the results of the conducted research, it was proposed to strengthen the structural system of the building, which was originally designed and constructed in accordance with the outdated standards SNiP RK 2.03-30-2006, in order to enhance its seismic resistance and ensure compliance with current seismic safety requirements.
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Field thermal imaging surveys of residential buildings – a prerequisite for the development of energy-efficient external enclosures

https://doi.org/10.58224/2618-7183-2024-7-6-1
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Abstract
The work involved a full-scale thermal imaging survey of a residential building during a hot period of time, where the effect of solar heating of the building's façade and the inner surface of the outer enclosure was studied, taking into account the orientation of the building and the time of the survey. As a result, it was found that the effect of solar heating on the building’s façade significantly increases the temperature on the façade surface, where, depending on the façade orientation and time, the building’s façade surface is exposed to heating from the east, west and south sides. Thus, the maximum values of the façade surface temperature reach 63.1°C, 57.0°C and 53.4°C, respectively, which is almost twice as high as the initial temperature values. Solar heating also has a significant effect on the temperature of the inner surface of the external enclosure, also depending on the façade orientation. Thus, on the east side in the morning, the surface temperature of the external enclosure increases by 3.8°C, which continues until 16:00. The influence of the sun provokes heating of the inner surface of the external enclosure of the living room on the western side by 4.2°C, and on the southern side the maximum temperature on the surface of the inner enclosure was observed in the period from 12:00 to 16:00, which exceeded the initial one by up to 3.8°C. At that, the influence of heating from the sun on the northern side was not observed. With that, it was found that the influence of solar heating of the building façade provokes deviations in the microclimate of the room, where the deviation in the permissible internal air temperature of the living room is 14.1% during the day, and in the optimal humidity by 13.3% in the afternoon. The findings of this study can be taken into account when designing or developing new energy-efficient external enclosing wall structures, where the criterion of heat resistance must also be taken into account in parallel with the criterion of heat protection in the climatic features of the Republic of Kazakhstan.
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Construction and climatic certification of an area as a prerequisite for development of energy-efficient buildings and their external wall constructions

https://doi.org/10.58224/2618-7183-2024-7-5-1
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Abstract
Construction and climatic certification and, therefore, the orientation of buildings and building envelopes are important aspects of design and construction, especially in the conditions of specific climatic zones of the Republic of Kazakhstan. The main points that should be taken into account when determining climatic conditions, including in certification: the study of climatic conditions at the construction site, such as solar radiation, temperature, humidity, wind and other meteorological factors. This permits to select the appropriate building structures, materials and technologies. Based on climatic data, an energy saving strategy is developed to ensure an optimal level of comfort in buildings with minimal costs for heating and air conditioning, as well as to minimize overheating in the summer and provide optimal solar lighting, take into account the prevailing wind directions to minimize the negative impact of strong winds on structures and improve ventilation. The developed methodology of construction and climatic certification and factors of the natural and climatic environment, entered into the passports of the construction object, is the basis for the creation of design documentation of the Architecture section to ensure optimal conditions for the design, construction and operation of buildings and structures.
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Analysis of thermal efficiency of external fencing made of innovative ceramic blocks

https://doi.org/10.58224/2618-7183-2024-7-3-1
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Abstract
The paper presents a comprehensive theoretical study of the external fencing structure made of innovative Porortherm 38 ceramic blocks in comparison with traditional structures made of solid ceramic brick, hollow ceramic brick and gas block. The study was conducted in the climatic conditions of Shymkent city, South Kazakhstan. The middle temperature values of the frostiest 5 days with a provision of 0,92 were adopted as the external temperature. The results of the study of the actual resistance (Rf) of the structures under study showed that all adopted structures meet the condition Rf˃Rreq, while the actual resistance of the new structure is 1.3 times more efficient than traditional ones. The analysis of temperature fields showed that the new structure is 2% more efficient than traditional ones. Moreover, no additional insulation costs are required. The obtained results were also confirmed by computer modeling in the ELCUT software package. The results of calculating the humidity regime showed that a condensation area appears in almost all the structures under consideration. The results of calculating the amount of moisture evaporated from the multicoat structure of the external fencing during the torrefaction period showed that all the accumulated moisture will evaporate during the specified period, the calculation of the condition of inadmissibility of moisture accumulation in the structures of external fencings for an annual period and for the period of moisture accumulation showed that all the considered structures meet the requirement . The results of calculating the air regime of multicoat structures of external fencings also showed that all structures including the new one meet the condition . The result of calculating the value of thermal inertia (D) in the proposed structure is up to three times more efficient than traditional structures, which applies to structures with high inertia (7˂D). The obtained results of the study indicate that the new proposal of a structure made of ceramics is cost-effective, innovative blocks can be proposed as a supplement to the register of materials of existing standards.
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Analysis of the effect of porosity on thermal conductivity with consideration of the internal structure of arbolite

https://doi.org/10.58224/2618-7183-2024-7-3-4
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Abstract
A theoretical study of the effect of porosity and internal structure of the exterior envelope in the ANSYS and BLENDER software systems has been carried out in the paper. As an example of exterior enclosure structure, an arbolite block with porosity up to 20% and fiber structure in the direction along and across the heat flux, as well as randomly and at an angle of 45° was studied. As a result of the study, it was found that the significant effect of the heat flux dependence on the porosity of the material is the porosity of the block over 10%, which reached up to 5.92%, and with porosity up to 5% showed a difference of 1.3%. At the same time, the fiber structure also showed a significant difference from 8.16% to 15.33% depending on the fiber direction. At the same time, the analysis of the effect of porosity on the thermal conductive value also showed a difference of up to 15.33% for the same value of heat flux. At the same time, the influence of fiber structure shows an additional difference of up to 5.9%. The results of the study showed that the most thermally conductive arbolite blocks are, those in which the direction of fibers are located along (along the X axis) and at 45 ° relative to the structure of fibers across (along the Y axis) and random, the difference of which was up to 1.6%. The obtained results of this study, further excluding the costly experiments to determine the coefficient of thermal conductivity can be used to accurately estimate the coefficient of thermal conductivity of external envelopes made of arbolite blocks, considering porosity and fiber structure in the design of residential buildings.
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Thermovision study of a residential building under climatic conditions of South Kazakhstan in a cold period

https://doi.org/10.58224/2618-7183-2024-7-2-1
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Abstract
In this study, a nine-storey residential building was examined for thermal protection, located in Shymkent, Republic of Kazakhstan. Two two-room flats were considered with the possibility to inspect the exterior envelopes in four orientations. The examination was carried out at different times of the day according to three criteria: exterior envelope in the form of corner joints, translucent enve-lope in the form of window openings and the exterior façade of the building. The study found that the temperature at the surface of the room joints at lunchtime increased from 0.8% to 12% depending on the orientation of the exterior envelope. At the same time, it was found that in the morning and evening hours the temperature inside the living rooms is maintained at 25.8 - 26.5ºC due to excessive con-sumption of heat energy by increasing the heating power up to 15.6% relative to lunchtime, which leads to an excessive increase in air temperature by 7 - 18%. The value of humidity of living rooms also showed non-compliance with the optimal value by 3 - 15% relative to the current norms. As a result of the analysis of thermograms of translucent openings it was found that the surface temperature of the envelope at lunchtime increased by 9.9 - 23.2% in all cases of orientations, and the surface tem-perature of translucent openings of southern orientation is on average 18.2% higher relative to other orientations, which also indicates the influence of solar radiation on the thermal values of translucent openings. The analysis of thermograms and temperature of characteristic points of the external façade with regard to orientations showed a temperature difference from 7.5ºC to 21ºC depending on the ori-entation of the building, where the most exposed to solar radiation façade of southern orientation, which showed an increase in surface temperature by 3 times. Thus, the obtained results of the study will further contribute to the development of energy-efficient designs of external enclosures, consider-ing the influence of all factors on the process of heat exchange, which is the main objective of the au-thors’ comprehensive study.
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Field thermovision study of externsl enclosure for multi-storey residential building under climatic conditions of Northern Kazakhstan

https://doi.org/10.58224/2618-7183-2024-7-1-1
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Abstract
An in-place thermovision study was carried out in a multi-apartment apartment building of high comfort in a cold period of the year, located in the Northern part of the Republic of Kazakhstan in the work. The study result showed the presence of significant problems on thermal protection at the edge and inner corner fences where the temperature difference between the inner surface of an enclosure and the internal temperature was 6.4 - 19.4ºC. An analysis of thermograms of window joints in living rooms also showed a significant temperature drop from -9.3ºC to 18ºC, where total vulnerable area was up to 10%. Thermograms of window-sill joints of living rooms also showed a temperature drop to -21.1 ºC with an area of 15.7 %. The temperature on a reinforced concrete column’s inner surface showed a value of 6.5 ºC, which is typical for an area of 34.8 %. An analysis of outside and inside temperatures showed that as the temperature drops from -7 ºC to -23 ºC during the day, the inside temperature of the room remains relatively stable at 25.3 - 26.1 ºC, although there are problems with the thermal protection of the enclosures, which indicates overconsumption of heat energy. Moreover, the internal air temperature exceeds the permissible temperature for living rooms by 1.3 - 2.6 ºС. An analysis of air humidity also showed unsatisfactory values, which during the day varied from 17.4% to 21.2%. The deviations identified during the survey indicate the presence of problems on thermal pro-tection of external enclosures, which require additional surveys aimed at further development and op-timization of external enclosure designs to obtain optimal values in the issue of energy saving, consid-ering the climatic characteristics of the Kazakhstan regions.
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