Technical Wear Research Articles

НАПРАВЛЕНИЯ ПОВЫШЕНИЯ ЭНЕРГОЭФФЕКТИВНОСТИ СИСТЕМ ГЕНЕРАЦИИ ТЕПЛОВОЙ ЭНЕРГИИ В РАМКАХ ТЕПЛОЭНЕРГЕТИКИ РОССИИ

The article discusses the directions of improving the energy efficiency of heat generation systems involved in solving heat supply problems in the Russian Federation. The thermal energy generation system is considered as a set of subsystems of heat generating equipment, movement of gaseous media, preparation and transfer of coolant, reduction and disposal of emissions. Each subsystem consists of corresponding elements. The energy efficiency measures under consideration are analyzed in accordance with the impact on the impact element, other elements of the subsystem, the heat supply system as a whole, as well as other energy supply systems. Due to the importance of environmental problems, as well as the need to optimize the generation of thermal energy by reducing losses at the stages of production, transportation and consumption, elements related to the reduction and disposal of emissions, including thermal pollution of the environment, are allocated to a separate subsystem of the heat generation system. The necessity of a comprehensive consideration of the heat generation system, along with related power supply and energy consumption systems, is shown. Inventory of energy flows, comparison of the actual with the necessary and sufficient amount of energy allows you to determine the possible and necessary ranges of regulation of elements of subsystems of the thermal energy generation system. Due to the large technical wear of heat generation equipment and significant changes in the connected heat load, the need for the development of energy-efficient tasks for the design of reconstruction and new construction of heat generating facilities by start-up complexes is increasing. This makes it possible to achieve the objectives of improving energy efficiency after each stage of reconstruction or construction, as well as to carry out long-term and high-quality planning.

Studies of Masonry Structure Technical Wear in Mining Areas

Studies of Masonry Structure Technical Wear in Mining Areas

Analysis of the Technical Condition of a Late 19th Century Public Building in Łódź

Heritage building structures in many situations contribute unique value to national cultural heritage. In engineering practice, monitoring of historic structures includes visual assessment. This article assesses the condition of the concrete in one of the most recognizable buildings in Łódź, the former German Reformed Gymnasium, located at Tadeusza Kościuszki Avenue. The paper reports a visual assessment of the structure and the degree of technical wear affecting selected structural components of the building. A historical analysis of the building's state of preservation, characterization of the structural system, and an assessment of the condition of the floor-slab concrete were carried out. The state of preservation of the eastern and southern facades of the building was found to be satisfactory, while on the western side (with the courtyard) the facade is in a poor state of preservation. Tests were also conducted out on concrete samples taken from individual ceilings. The concrete cores were tested for compressive strength, water absorption, density, porosity, and carbonation depth. Corrosion processes including the degree of carbonization and the phase composition of the concrete were identified by X-ray diffraction. The results are indicative of the high quality of the concrete produced more than 100 years ago.

EFFICIENCY OF TERRITORY USE IN THE RECONSTRUCTION OF A 5-STOREY BUILDING TAKING INTO ACCOUNT CURRENT REGULATORY AND LEGAL TOWN PLANNING REQUIREMENTS

EFFICIENCY OF TERRITORY USE IN THE RECONSTRUCTION OF A 5-STOREY BUILDING TAKING INTO ACCOUNT CURRENT REGULATORY AND LEGAL TOWN PLANNING REQUIREMENTS

Comparison of Cattle Housing Systems Based on the Criterion of Damage to Barn Equipment and Construction Errors.

Simple SummaryAs a result of many years of use, dairy cattle barns are subject to gradual wear and degradation. Damage to technical equipment can be identified in many areas in the barn. These areas are used by dairy cattle, so it is important to recognize the problem of damage and the associated health risks for animals. The problem of damage to internal equipment (e.g., damage to the floor, partitions between lying stalls, feed ladders, drinking bowls) applies to both tie-stall and freestall barns, which are the most common in dairy farms. Such premises became an inspiration to compare barns with a tie-stall system, a freestall system and their individual areas (lying, feeding, milking and social) in terms of the amount of damage but also construction errors. Most damage per one barn was found in the feeding area of objects with a tie-stall housing system. More cow health problems (e.g., laminitis, hoof problems) were identified in the barns with the freestall housing system. Equipment failures and construction errors may disrupt efficient and animal-safe dairy production in the barn. The results of the research study may be an incentive for farmers to check the barns in terms of their technical wear.Dairy cattle housing systems are the subject of numerous studies, in which a strong emphasis is placed on the comparison of animal welfare, animal behavior, production indicators and labor inputs. Dairy cattle housing systems are linked to specific livestock buildings, which is a prerequisite for undertaking studies comparing barns and their technical equipment. The aim of the study was to compare barns with two types of housing systems, i.e., tie-stall and freestall, including the identification of technical wear in various areas used by animals. This objective was linked to the assessment of animal health problems in livestock facilities. The research covered 38 dairy farms, 19 of which kept cows in the tie-stall system and 19 in the freestall system. The barns in these farms were examined for technical damage and construction errors, assessed in four areas: lying, feeding, milking and social. The research results confirmed significant differences in the degree of damage to technical equipment in individual areas of barns and between barns with tie-stall and freestall housing systems. The conclusions indicate the need to link the degradation of barns and their technical equipment, as well as design errors with the evaluation of dairy cattle welfare in future studies.

Production of bakery products at the enterprises of Almaty region of Kazakhstan: assortment, quality, growth rates

The goal is to identify priority areas for innovative activities of enterprises for production of bakery products in Almaty region, which are socially significant food products, and baking industry is one of the leading sectors of food sector, in which it is important to improve quality, nutritional value and expand the range of bakery products. Methods – complex economic analysis, SWOT-analysis, questioning. Results – the state and pace of development of market for bread and bakery products in Almaty region and Almaty city are studied, the dynamics of their production in the region for 2016-2020 and growth rate are shown. By questioning consumers, the main criteria and reasons that guide them when choosing an assortment are shown. Currently, the market is experiencing increased demand for dietary bakery products of high quality, with added cereals. The level of technical modernization of the leading bakery enterprises of Almaty region was analyzed. The authors note that used equipment and tools are outdated, technical wear and tear on some of them exceeded 50%. Conclusions – the most important directions for increasing the innovative activity of enterprises in this sector are reflected, main factors influencing the efficiency of their functioning and stabilizing the situation on bread market are identified. With the constant increase in cost of raw materials and energy, manufacturers face the difficult task of keeping the prices of their products at the same level. This task can be solved only in terms of optimizing production costs and controlling price premium in retail outlets.

The life quality of the disabled as a result of diseases of peripheral nervous system

The article considers results of studying the quality of life of disabled patients because of diseases of peripheral nervous system. The significantly low level of indices of quality of life self-assessment was established on all scales of SF-36 questionnaire that are from 3 to 7 times lower than similar indices in population of Russia. The assessment of quality of life of disabled patients is necessary to determine effectiveness of applied rehabilitation measures and application of obtained results in planning further rehabilitation and habilitation activities.

PROBLEMS OF ENTERPRISES FOR EXTERNAL LIGHTING OF SETTLEMENTS AND DIRECTIONS OF THEIR SOLUTION

The article investigates the existing problems of outdoor lighting enterprises in settlements and identifies areas for their leveling. The data on the number of electricity meters consumed by outdoor lighting systems of settlements and the costs of their maintenance are analyzed. It is revealed that the positive dynamics is the increase in the share of differential metering devices. But, due to the increase in the cost of electricity, the cost of maintaining one light point in 2018 increased compared to 2017 and amounted to 255.2 UAH. Positive dynamics is marked by a decrease in the amount of electricity consumed and the costs per operation of one light point, especially in the context of rising electricity tariffs, the reason for this reduction in costs is the increase in LED light sources. The study of electricity distribution companies providing lighting of settlements made it possible to identify certain common problems, namely: insufficient working capital, unsatisfactory liquidity of enterprises, general technical wear and innovative backwardness of electricity distribution equipment, high operating costs and insufficient lighting equipment , lack of funding from local budgets for the modernization of urban outdoor lighting, lack of long-term strategic planning of innovative activities of enterprises and measures to attract investment resources, lack of efficiency in collecting and publishing information. It is established that one of the main directions of solving the existing problems of electricity distribution companies, given that most of them are communal enterprises, is to intensify the attraction of investment resources from various sources of investment, including through public-private partnerships, which is also confirmed world experience in the development of such enterprises. Attracting investment resources on the basis of public-private partnership makes it possible to: apply the latest innovative technologies, partially transfer project risks to a private partner, reduce the cost of investment projects through the use of optimal technologies and motivation of the private partner.

Correlation between Defects and Technical Wear of Materials Used in Traditional Construction.

The degree of technical wear of old buildings, which are made of basic materials (cement, concrete, steel, timber, plaster, brick) using traditional technology, is expressed by the size and intensity of damage to their elements. The topic of the research concerns old residential buildings from the turn of the 19th and 20th centuries, which are located in the downtown district of Wroclaw, Poland. The descriptive analysis and the analysis of the definitions of defects that occur in the elements of residential buildings, which were performed as random analyzes, do not allow defects to be considered as measurable variables at a level of visual investigation. The major drawback of the method that is used by experts when assessing the technical condition of civil engineering buildings is that it does not numerically express the magnitude (strength) of the defects. Therefore, an attempt was made to numerically express the relationship (if such a relationship exists) between the occurred defects of buildings and the extent of their technical wear process. When calculating the strength of this relationship, the method of determining the point biserial correlation coefficient for the measurable property and the dichotomous property was used. It was found that the direction of the relation is right-hand for all the tested building elements, but the strength of the correlation between the detected defects and technical wear shows a considerable span and depends on the conditions of the apartment house’s maintenance. As a rule, damage caused by water penetration and moisture penetration always shows correlations of at least moderate strength.

Identification of development drivers of using “green” technologies in investment and construction projects of the Russian Federation

A high level of energy consumption per GDP unit is typical for the territories of the Russian Federation. Technical wear and tear and obsolescence of technological and energetic equipment, high energy losses in buildings and structures are the main reasons that caused a high level of energy intensity of GDP. Rapid population growth and competition for limited resources have further increased the need to design and construct buildings using sustainable construction technologies. These buildings must be able to maintain quality of life and ultimately ensure longterm human survival. The construction industry plays an important role in preserving the environment through the rational use of resources and assets that require the immediate massive implementation of the principles and methods of sustainable construction. One of the components of the principles of sustainable construction is the use of “green” technologies in construction projects, reconstruction, and overhaul of structures. The Russian Federation has a huge potential in reducing the negative impact of the construction industry on the environment and the social sphere. That is why it is very important to develop methodological foundations which are conducive to the successful development of the so-called “green” construction market in all regions of the country. Therefore, it is necessary to identify the main constraints to the development of “green” technologies. This article is intended to identify obstacles to the implementation of the “green” construction from the general contractors’ point of view. The article identifies points of growth based on the identified problem areas. Growth points are needed to form further positive dynamics of construction volumes using “green” technologies. The identified development drivers will contribute to the expansion of demand and provide a multiplicative stimulating effect on related sectors of the investment and construction complex soon.

Bayes Conditional Probability of Fuzzy Damage and Technical Wear of Residential Buildings

The purpose of the research presented in the article is to identify the impact of the processes associated with the broadly understood maintenance of old residential buildings with a traditional construction on the size and intensity of the wear of their elements. The goal was achieved by analyzing the symptoms of the technical wear process, which involved the understanding of the mechanism of the occurrence of the phenomenon of damage, and the identification of the size and intensity of the damage to the elements of the evaluated buildings. The consequence of systematizing the most important processes that influence the loss of functional properties of residential buildings was the creation of the authors’ own qualitative model and its transformation into a quantitative model. This, in turn, enabled a multi-criteria quantitative analysis of the cause and effect phenomena—“damage-technical wear”—of the most important elements of downtown tenement buildings to be carried out in fuzzy conditions, i.e., uncertainty concerning the occurrence of damage and the wear process. The following key question was answered in the subjective expert assessment of the technical condition of an evaluated residential building: what is the probability of the wear of an element, which may be more or less correlated with its average maintenance conditions, or more simply, what is the probability that the element is more or less (approximately) worn? It has been proven that the conditional probability of the technical wear of an element in relation to its damage increases with the deterioration of the maintenance conditions of the building, and this increase is very regular, even in the case of different building elements. This probability is characterized by a low standard deviation and a narrow range of the dispersion of results in the case of various elements with regards to each of the considered building maintenance conditions.

Fuzzy Relations Matrixes of Damages and Technical Wear Related to Apartment Houses

The research presented in this article was conducted on a representative and purposefully selected sample of 102 residential buildings that were erected in the second half of the nineteenth and early twentieth centuries in the downtown district of Wroclaw (Poland). The degree of the technical wear of an old residential building is determined by the conditions of its maintenance and operation. The diagnosis of the impact of the maintenance of residential buildings on the degree of their technical wear was carried out using quantitative methods in the categories of fuzzy sets and also by using the authors’ own models created in fuzzy conditions. It was proved that the expression of the operational state of a building, considered as the process that plays the greatest role in its accelerated destruction, is mechanical damage to the internal structure of its elements. This damage is determined in the categories of fuzzy sets and has a high frequency and a cumulative effect of occurrence, which are characteristic for buildings in satisfactory and average maintenance conditions. The use of simple operations in fuzzy set calculus enabled the impact of elementary damage that occurs with a specific frequency, as well as the measure of its correlation on the observed technical wear of building elements to be considered. As a result, it was possible to identify the elementary damage that determines the degree of the technical wear of a building element. For each of the selected building elements, the maximal and minimal fuzzy relational equations (damage and technical wear) were determined. Their solutions were given in the form of clear relational matrixes that constitute big data arrays. They define the domain and range of the maximal and minimal fuzzy relations, the height of the fuzzy relations, their differences, and the place of their occurrence between the maximal and minimal dependencies.

Damage and Technical Wear of Tenement Houses in Fuzzy Set Categories

The results and conclusions of the research presented in the article concern the topic of the technical maintenance and wear of traditionally erected residential buildings. The cause and effect relations between the occurrence of damage to the elements of tenement houses, which are treated as an expression of their maintenance conditions, and the size of the technical wear of these elements were determined in a representative and purposefully selected sample of 102 apartment houses built in the second half of the 19th and early 20th centuries in the Wroclaw, Poland downtown district “Srodmiescie”. Recognition of the impact of the maintenance of residential buildings on the level of their technical wear was carried out using quantitative methods from fuzzy set categories, and also with the use of the authors’ own model. The created model, based on the Zadeh function, was created in fuzzy conditions for the purpose of assessing the degree of damage to selected building elements. The treatment of the problem with regard to fuzzy criteria allowed for the synthesis of elementary criteria, which give the greatest approximations at the technical research stage of a residential building, into a global assessment of the degree of the wear of its elements. Moreover, it also significantly reduced the subjective factor of this assessment, which had a significant impact on the results of the research obtained in the case of good, medium and poor conditions of tenement houses. It was proven that the conditions of maintenance and use of buildings determine the amount of technical wear of their elements. The state of exploitation of the examined tenement houses is reflected in the mechanical damage to the internal structure of the elements (determined in fuzzy categories). This damage has a significant frequency and cumulative effects, and is characteristic for buildings with satisfactory and average maintenance.

Overdurability and Technical Wear of Materials Used in the Construction of Old Buildings.

The technical maintenance of old tenement houses traditionally constructed is an ongoing problem, and will continue to be so in the coming years. The subject of the article includes old residential buildings from the turn of the XIX and XX centuries, which are a part of Wroclaw’s downtown district. They can be understood as an essential link in the process of shaping the cultural and social microenvironment of man. The ability of them to meet the multiple expectations of residents depends on the natural aging of tenement houses’ materials, the methods of their maintenance and use, and the influence of the many factors that cause their accelerated wear. The assumed durability is the main reference parameter of the changing age of the inspected tenement houses. The course of the theoretical and observed degree of the technical wear of these buildings was compared with their durability. For the age of these buildings, the technical wear should reach 100%. It was observed that in the first period of use of tenement houses, the phenomenon of “infradurability” occurs, and after exceeding a certain age—depending on the maintenance conditions of the building—the phenomenon of “overdurability” of the building occurs. It was shown that the durability of important elements of old buildings, as a parameter that was defined “a posteriori”, ranges from 153 to 177 years, and is greater than the corresponding literature values indicated “a priori”. The probability of reaching such an age of an element, in which the observed values of technical wear exceed the theoretical values, is much higher than the probability of an opposite event. A comparative analysis of the distribution functions of these probabilities indicates that the probabilities of theoretical wear values are higher than those observed in the case of the assumed literature durability of elements. There is also an inverse relationship for durability that corresponds to the age of the oldest examined elements of tenement houses.

СРОК СЛУЖБЫ КАК ПАРАМЕТР ОБОБЩЕННОГО УЗЛА ПРИ РАСЧЕТЕ ИНДЕКСА ТЕХНИЧЕСКОГО СОСТОЯНИЯ ЭНЕРГЕТИЧЕСКОГО ОБОРУДОВАНИЯ

In accordance with the energy digitalization program, the single integral indicator - the technical condition index (TCI) - is used for the assessment of the technical condition and physical wear and tear of energy equipment. Service life is one of the components of this index. The article discusses the influence of the service life of power equipment on the final value of the index, explains the contradictions in assessing wear on TCI and on the lifetime indicators. For aging equipment that has reached the end of its design life, it is suggested to use the individual service life or individual period of safe operation extension as the normal value of service life under the assessment of TCI.

A method for determining the financial cost of damage to buildings caused by seismic ground vibrations

A method for determining the value of the damage to a single-family residential building located near an open-pit mine caused by ground vibrations is presented. The article describes how to objectively determine the degree of actual wear and tear to a residential building (Zr) affected by ground vibrations created during rock mining using blasting. It consists of the method of "weighted average degree of technical wear and tear of individual elements" known from literature and used to calculate the actual wear and tear of the building. The natural wear and tear of the building is then calculated from dependences given in the literature. The percentage of the building’s natural wear and tear (Zn) is subtracted from the percentage of the building’s actual wear and tear. As a result of the subtraction, a percentage of accelerated wear and tear of the building (Zb), which is caused by vibrations of the ground during rock blasting, is obtained. Multiplying the percentage of accelerated wear and tear of the building by the value of a new building gives a value of the damage caused by ground vibrations. Examples of determining the value of the damage caused by ground vibrations in practice are described.

ІННОВАЦІЙНО-ЛЮДСЬКИЙ ПОТЕНЦІАЛ У МЕНЕДЖМЕНТІ БУДІВЕЛЬНОЇ ГАЛУЗІ

During the operation of infrastructure assets excessive action of transport and natural vibrations, water-heat and low-temperature fluctuations, soil leaching leads to undesirable changes in the current criteria of their safety, premature technical wear of surfaces, cracks, irregularities, subsidence, increased seismic fluctuations and floods. sustainability of infrastructure assets. Taking into account the above negative trends, the article analyzes the positive and negative factors of the impact of innovation – human capital on management in the construction industry. Innovative – human capital of labor resources in the context of global digitalization requires constant professional development, human ability to effective research and innovation, it emphasizes the importance of updating educational programs in the global context and the principles of sustainable development. Therefore in the specified conditions harmonization of university business – education in the field of processes and technologies of management in building construction is a priority. In general, the strategies, technologies and processes of corporate management of infrastructure assets operating in the latest global conditions are actively used in such projects as interdisciplinary cooperation and partnership of stakeholders, including universities; city, departments for infrastructure asset management; international corporations; transfer of intellectual capital, exponential training of the young generation and transprofessionalization of the working population; "green" clean cities; protection and preservation / preservation of cultural heritage; design and operation of "smart" road systems; digital infrastructure; conservation / preservation of the marine ecosystem; rehabilitation / rejuvenation of existing funds. It is expected that the results of research should contribute to the real provision of quality management in the construction industry, innovative technologies and processes of urban management, planning, development, reconstruction and operation of settlements and regions to meet the needs of the population and business – production.

Influence of Age on the Technical Wear of Tenement Houses

The research presented in the article, which includes methods, models, and conclusions, contains synthetic and analytical model solutions concerning the problems of the technical maintenance and wear of residential buildings with a traditional construction. The cause and effect relationships between the occurrence of damage in the elements of tenement houses (treated as proof of their maintenance conditions), and the size of the technical wear of these elements were determined using a representative and purposefully selected sample of 102 residential buildings erected during the second half of the nineteenth and early twentieth centuries in Wroclaw’s “Downtown” district. Quantitative damage analysis, which was carried out using empirical (visual) methods of assessing the technical condition of a building, indicates the type and size of damage to the building’s elements that are characteristic for the relevant maintenance conditions. Research concerning the cause–effect relationships (“damage–technical wear”) in observed states allows for a numerical approach to the impact of building maintenance conditions on the degree of the technical wear of its components. The maintenance and exploitation conditions determine the degree of the technical wear of the elements of an old residential building. The exploitation condition of these buildings is manifested by damage to elements caused by water and moisture penetration, which is especially important for poorly maintained buildings. The article shows that the age of the elements of an old residential building with a traditional construction is of secondary importance in the process of the intensity of losing its serviceability value. It was calculated that no more than 30% of the damage of building components is explained by the passage of time, and it is therefore not age that determines the course of the technical wear of the elements of the analyzed tenement houses.

Analysis of Polarization and Depolarization Currents of Samples of NOMEX®910 Cellulose–Aramid Insulation Impregnated with Mineral Oil

The article presents results of laboratory tests performed on samples of NOMEX®910 cellulose–aramid insulation impregnated with Nynas Nytro 10× inhibited insulating mineral oil using the polarization and depolarization current analysis method (PDC Method). In the course of the tests, the insulation samples were subjected to a process of accelerated thermal degradation of cellulose macromolecules, as well as weight-controlled dampening, thereby simulating the ageing processes occurring when using the insulation in power transformers. The effects of temperature in the ranges typical of normal transformer operation were also taken into account. On the basis of the obtained data, the activation energy was then fixed together with dominant time constants of cellulose–aramid insulation relaxation processes with respect to the temperature and degree of moisture, as well as thermal degradation of cellulose macromolecules. It was found that the greatest and predictable changes in the activation energy value were caused by the temperature and the degree of moisture in the samples. A similar conclusion applies to the dominant time constant of the relaxation process of cellulose fibers. Degree of thermal degradation samples was of marginal importance for the described parameters. The final outcome of the test results and analyses presented in the article are regression functions for the activation energy and the dominant time constants depending on the earlier listed parameters of the experiment, which may be used in the future diagnostics of the degree of technical wear of cellulose–aramid insulation performed using the PDC method.

Age-related efficiency loss of household refrigeration appliances: Development of an approach to measure the degradation of insulation properties

Despite the omnipresence of household refrigeration appliances, there is still a lack of knowledge about their age-related efficiency loss over time. Past studies provide basic evidence for increasing electricity consumption of cooling appliances with ageing but fail to investigate the associated technical wear. Concentrating on the degradation of the thermal insulation, we first determined the ageing process of sealed samples of polyurethane rigid foam by investigating changes in cell gas composition and thermal conductivity over time. Simultaneously, the main challenge was to develop an approach that investigates the age-related efficiency loss of the insulation without its destruction. This testing procedure is referred to as the Bonn method. The non-destructive Bonn method was applied to varying refrigerator models in a series of successive experiments to evaluate the insulation degradation over time. Subsequently, the physical relationship between the test value of the Bonn method and the heat transfer through the multi-layered compartment walls of domestic refrigeration appliances was established, ultimately characterising the degrading insulation in terms of increasing heat transfer. Our results give substantiated evidence that the efficiency loss of cooling appliances is greatly influenced by insulation degradation over time. The ageing of sealed samples of polyurethane rigid foam indicates a large initial increase of thermal conductivity by 15% within the first year, corresponding to a change in cell gas composition. These results are in line with those of the Bonn method, emphasising an increasing heat flow through the multi-layered compartment walls of domestic refrigerators with ageing. Therewith, the present study is of significance to a wide range of stakeholders and forms the basis for future research.