Bulletin of Odessa State Academy of Civil Engineering and Architecture最新文献

{"title":"RESEARCH OF SURFACE PROPERTIES OF FABRICS FOR MANUFACTURE OF TENTS","authors":"Y. Tsapko, O. Bondarenko, A. Tsapko, Yuriy Sarapin, D. Zherebchuk","doi":"10.31650/2415-377x-2022-86-86-95","DOIUrl":"https://doi.org/10.31650/2415-377x-2022-86-86-95","url":null,"abstract":"The operation of easily erected structures made of flammable textiles encourages the use of fire protection, as the operation may ignite tarpaulin fabric, which is a flammable material. Therefore, studies aimed at determining the patterns of formation of an elastic layer of fire-retardant coating on fabrics with a composition based on mixtures of organic and inorganic substances, characterized by the necessary technological properties, are relevant. The paper presents the results of studies of free surface energy, as well as its components (polar and dispersed) for tarpaulin fabric and methods of its change when using a fire-retardant coating. A drop of coating was applied to the sample with a pipette during the test. After reaching the equilibrium drops, its height and diameter were determined with a microscope. The sequences of polarity change and their relationship with the main component of the fabric after the formation of the flame retardant coating, which are consistent with the structural and functional features of the tarpaulin fabric. The resulting fabric is characterized by a reduced property of water absorption, as the free surface energy changes 2.3 times and the polarity 2 times, which is associated with a decrease in the surface tension of the coating. Given the above, it was found that the polarity of the canvas fabric is close to the polarity of the flame retardant coating, which is difficult to wet the material. Instead, the addition of a foaming agent reduces the polarity of the coating and increases the wettability, which allows you to effectively process the canvas fabric. Thus, when applying a comprehensive approach to the study of wettability, polarity, interfacial tension, you can choose stable technologies for new products from fire-retardant fabric and expand their scope.","PeriodicalId":273453,"journal":{"name":"Bulletin of Odessa State Academy of Civil Engineering and Architecture","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124766817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ORGANIZATION OF ENERGY EFFICIENT ECOLOGICAL SETTLEMENTS WITH PREFABRICATED MODULAR BUILDINGS FOR TEMPORARY AND LONG-TERM LIVES OF LIVING, IN CONNECTION WITH THE WAR IN UKRAINE","authors":"Y. Selikhova","doi":"10.31650/2415-377x-2022-86-62-68","DOIUrl":"https://doi.org/10.31650/2415-377x-2022-86-62-68","url":null,"abstract":"The cities of Ukraine are our pride! It was the envy of prominent Ukrainian cities that provoked the aggressor's attack on our native lands. It should be noted that most Russian cities, which are more remote, cannot be proud of their amenities: there is no sewerage or water supply, unpaved streets quickly turn into swamps of sticky dirt. On the 24th of February 2022, the war began, and Russian Federation attacked Ukraine on all sides of the common border, from Luhansk to Chernihiv. The enemy army fired artillery at Ukrainian border posts. Hometown Kharkiv is a city in the northeast, the first capital, the scientific center of Ukraine, subjected to massive bombing. Every day the occupiers purposefully destroy more and more civilian infrastructure, because of which the evacuation began. The news notes that in the first days of the war, every day about 30,000 people go from the Kharkiv railway station to safe places, to the west of the country and abroad. That is why the article considers the best ways to develop the territories of the western part of the country, through the organization of energy-efficient ecological settlements with prefabricated modular buildings for temporary and long-term residence of people who lost their homes because of the war. In the formation of energy-efficient ecological settlements, the main basic aspects are laid down, including: minimization of impacts on the existing natural environment, use of processes on the way to improving urban planning, implementation of rational spatial solutions, ensuring resilience of settlements to disasters and war, application renewable energy sources (use does not lead to additional heating of the atmosphere, so this energy is waste-free and does not pollute the atmosphere), ensuring efficient water supply and rational use, development of underground space and conservation of natural areas. innovative living space, with the necessary, comfortable conditions that will serve for the development of new territories and for the revival of destroyed territories because of the war.","PeriodicalId":273453,"journal":{"name":"Bulletin of Odessa State Academy of Civil Engineering and Architecture","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125034652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FLOOD AS ONE OF THE MANIFESTATIONS OF HARMFUL EFFECTS OF WATER ON THE EXAMPLE OF FOUR UNITED TERRITORIAL COMMUNITIES OF ODESSA REGION","authors":"O. Miedviedieva, O. Miedviediev","doi":"10.31650/2415-377x-2022-86-96-103","DOIUrl":"https://doi.org/10.31650/2415-377x-2022-86-96-103","url":null,"abstract":"Flooding is one of the manifestations of the harmful effects of water, which is strongly manifested around the world. Its manifestations are recorded in Ukraine, mainly in the western regions. In the central, eastern and southern regions, periodic flooding is observed in the basins of large rivers (Danube, Dniester, Dnieper, etc.). With the beginning of the XXI century local periodic flooding is increasingly recorded in other areas. And if in the western regions we know almost everything about the causes and risks of flooding, in other areas there is almost no research and knowledge. Recognizing the significant economic and social damage from flooding at the state level, the Ministry of the Interior issued an order approving the \"Preliminary Flood Risk Assessment Methodology\" designed to carry out a preliminary flood risk assessment to identify areas with potentially significant flood risks in all areas river basins of Ukraine, and other possible sources of flooding, to minimize the negative consequences associated with flooding, which have an impact on human health, environment, economy, cultural heritage, etc. To do this, it was necessary to create a risk passport within each settlement (SM), but in most of them they are missing. The aim of the work is to show an effective approach to solve the problem of preventing such a negative phenomenon as flooding in the southern regions on the example of four associations of territorial communities (TC) of Belgorod-Dniester district (formerly Tatarbunary). The subject of the study were the factors of formation of this negative phenomenon within 34 SM. To solve this problem, an approach (algorithm), which consists of three main stages and the application of GIS programs Arc Map method 3D analysis, is proposed. At the same time, one of the main elements of the study was the existing hydraulic structures (HS). Based on the results of work within each state of emergency, the types, location, quantity and technical condition of the HS were determined. Maps of availability and technical condition of the HS, places of possible flooding with the direction of the main water flows are compiled in electronic form. The approach mentioned in this paper allows to minimize, and in some places to remove in the future such a negative phenomenon as flooding within a single state of emergency.","PeriodicalId":273453,"journal":{"name":"Bulletin of Odessa State Academy of Civil Engineering and Architecture","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132137900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FIELD TESTS OF THE EXPERIMENTAL CONSTRUCTIVE SCHEMES OF SOUND INSULATION OF THE FLOOR","authors":"I. Babiy, Y. Kalchenia","doi":"10.31650/2415-377x-2022-86-104-110","DOIUrl":"https://doi.org/10.31650/2415-377x-2022-86-104-110","url":null,"abstract":"The dynamic development of urbanization in Ukraine, as well as throughout the world, only increases the number of noise sources that disturb people. And this cannot be ignored, because insufficient sound insulation in an apartment threatens people with neuroses, changes in biorhythms, disorders of the digestive system, headache, memory impairment, problems associated with the perception of color. Therefore, you need to pay maximum attention to the sound insulation of premises during the construction of residential buildings. One of the main disadvantages of monolithic reinforced concrete multi-story buildings is noise. Penetrating into the apartment, he becomes the cause of irritation, an obstacle to sleep or concentrated work. It's no secret that high-quality soundproofing of premises plays an important role in our life and is necessary for our comfortable well-being. This article is devoted to solving an important issue of soundproofing floors in monolithic reinforced concrete multi-story residential buildings, namely from impact noise. The article discusses structural and technological schemes for sound insulation of a floor of three types, using various materials and their combinations to achieve the regulatory requirements for sound insulation from impact noise. When choosing the most rational structural and technological scheme, the results of a comparative analysis of organizational and technological indicators for the device of soundproofing the floor were used, as well as indicators of the reduced impact noise obtained as a result of full-scale tests. Full-scale tests were carried out in houses under construction. The technology for performing each type of floor will depend on the chosen structural and technological scheme, and in the future, the comfort of the residents of the apartment. Comparison of the structural and technological schemes in the future will allow to study and develop a modern and highly efficient structural and technological scheme of the floor sound insulation structure.","PeriodicalId":273453,"journal":{"name":"Bulletin of Odessa State Academy of Civil Engineering and Architecture","volume":"215 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114574613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ELEMENTS OF TECHNOLOGY FOR THE SURFACE GIPSUM COMPOSITE AND ITS PROPERTIES, AS A FACING MATERIAL","authors":"V. Tarasevych, Yu. G. Gasan","doi":"10.31650/2415-377x-2022-86-78-85","DOIUrl":"https://doi.org/10.31650/2415-377x-2022-86-78-85","url":null,"abstract":"The paper considers the issues of obtaining a composite material based on gypsum, fly ash and sulfur with improved performance. Regularities of impregnation of a gypsum sol matrix with a sulfur melt are established, taking into account the capillary-porous structure of the gypsum sol stone and the physical and technical properties of sulfur. The conducted studies make it possible to determine the sulfur mass transfer coefficient ams and the maximum sulfur-containing Us in impregnated products, depending on the initial values of the sulfur melt temperature, water-solid ratio and fly ash content. This allows to determine quickly and effectively the duration of impregnation to a given sulfur content for a specific composition and size of gypsum products. Technological factors influencing the hardening coefficient, water resistance and chemical resistance of gypsum ash products impregnated in sulfur melt have been studied. An analysis of the results shows that the strength of samples impregnated with sulfur increases while the degree of filling of the pore space with it is increasing. So, with increase in the relative sulfur content (v = Us / Usmax) from 0.30 to 0.90, the compressive strength increases from 10.1 to 42 MPa. It has been established that water resistance of the impregnated samples significantly depends on the degree of impregnation and the amount of fly ash. The experiments carried out give reason to believe that the material based on gypsum, ash and sulfur refers to waterproof materials, since the softening coefficient is higher than 0.7. It has been established that gypsum and gypsum samples impregnated with sulfur melt have a chemical resistance coefficient of at least 0.7, which allows them to be classified as chemically resistant. The resulting sulfur-gypsum composite is distinguished by high strength, water and corrosion resistance to aggressive environments of livestock complexes, food and chemical industries, where it should be used in the form of special facing products.","PeriodicalId":273453,"journal":{"name":"Bulletin of Odessa State Academy of Civil Engineering and Architecture","volume":"148 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116526281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"EVALUATION OF FIRE-PROTECTIVE ABILITY OF NEWLY CREATED FIRE-PROTECTIVE COATINGS OF STEEL STRUCTURES","authors":"A. Kovalov, Y. Otrosh, V. Tomenko, O. Vasylyev","doi":"10.31650/2415-377x-2021-85-79-88","DOIUrl":"https://doi.org/10.31650/2415-377x-2021-85-79-88","url":null,"abstract":"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.","PeriodicalId":273453,"journal":{"name":"Bulletin of Odessa State Academy of Civil Engineering and Architecture","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114281366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"STUDY OF SPATIAL PROBLEMS OF DYNAMIC STABILITY OF REINFORCED CONCRETE FRAMES","authors":"V. Fomin, І. Fomina","doi":"10.31650/2415-377x-2021-85-62-70","DOIUrl":"https://doi.org/10.31650/2415-377x-2021-85-62-70","url":null,"abstract":"Abstract. The article proposes a method for constructing areas of dynamic instability of reinforced concrete frames in the space of parameters (frequency and amplitude) of seismic and operational dynamic impacts that cause the appearance of longitudinal forces in the bars of structures, which periodically change in time and lead to an unlimited increase in amplitudes of transverse vibrations when the values of these parameters are in the areas of instability. The proposed method is demonstrated by a specific example, which considers the spatial problem of dynamic stability of a П-shaped frame with two concentrated masses located on it, which are under the action of vertical periodic forces. These forces create periodic longitudinal forces in the vertical rods of the frame. Areas of dynamic instability of the frame are constructed. From the point of view of human activity, fluctuations can be both beneficial and harmful. We can observe vibrations of various buildings, structures, bridges, which cause additional stresses and deformations of these structures, have a harmful effect on their safe functioning. Too intense fluctuations lead to serious consequences. This leads to the destruction of individual elements of the structure and, as a result, to accidents. The most destructive effect of vibrations is observed during earthquakes and explosions. The study of vibrations is of great practical importance. This avoids the unwanted effects of fluctuations by limiting their level. Only on the basis of a deep study of various types of vibrations can important practical problems of the dynamics of structures be solved. Solving dynamics problems is a complex problem. In contrast to static calculation, when studying oscillations, one has to take into account an additional factor – time. The dynamic design of structures provides them with bearing capacity under the combined action of static and dynamic loads. A construction will be considered as a system with an infinite number of elementary masses distributed over it with an infinitely large number of dynamic degrees of freedom.","PeriodicalId":273453,"journal":{"name":"Bulletin of Odessa State Academy of Civil Engineering and Architecture","volume":"157 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127366148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"THE INFLUENCE OF HYDROPHOBIC COATING ON THE EFFICIENCY OF FIRE PROTECTION OF TEXTILE MATERIALS","authors":"Y. Tsapko, O. Bondarenko, А. Tsapko","doi":"10.31650/2415-377x-2021-85-119-127","DOIUrl":"https://doi.org/10.31650/2415-377x-2021-85-119-127","url":null,"abstract":"Abstract. The analysis of fire-retardant materials for fabrics is carried out and it is established that the paucity of data for explanation and description of the process of fire protection, neglect of elastic coatings, leads to ignition of fabric structures under the action of flame. The development of reliable methods for studying the conditions of fire protection of fabrics leads to the creation of new types of fire protective materials. Therefore, it becomes necessary to determine the conditions for the formation of a barrier both for high temperatures and for leaching in the presence of precipitation and to establish a mechanism for inhibition of these processes. In this regard, full-scale tests were carried out and it was found out that when the flame is applied to untreated model samples of tent elements made of canvas fabric, the surface ignites and spreads the flame, which leads to their complete combustion within 105...120 s, instead, the model The fire-resistant sample of tent elements did not catch fire when ignited with a gasoline-based substance, and the flame did not spread. In this case, the final combustion was recorded for 3 c and the swelling of the protective coating reached 3...5 mm, and the surface was charred on an area of about 80% from the inside. When tested for fire retardant efficiency for a fire-resistant sample treated with a water repellent (5 % solution of GDJ-94), a decrease in efficiency and carbonization of the material was recorded, which amounted to 100%, and for a fire-resistant sample treated with a water repellent (5 % solution), a decrease in efficiency was recorded due to the combustion of paraffin and local burnout of the material, and carbonization was 100 %. Obviously, such a mechanism of influence of the fire-retardant coating is the factor regulating the process, which preserves the integrity of the object. Thus, there is reason to argue about the possibility of targeted regulation of the processes of fire protection of the fabric by applying coatings capable of forming a protective layer on the surface of the material, which inhibits the rate of heat penetration.","PeriodicalId":273453,"journal":{"name":"Bulletin of Odessa State Academy of Civil Engineering and Architecture","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133869045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"JUSTIFICATION OF THE SEARCH FOR THE COMPOSITION AND TECHNOLOGY OF PRODUCTION OF HEAT INSULATING MATERIAL OF HIGHER STRENGTH","authors":"A. G. Nevynsky, S. Kel’ina, V.A. Chvyr","doi":"10.31650/2415-377x-2021-84-87-100","DOIUrl":"https://doi.org/10.31650/2415-377x-2021-84-87-100","url":null,"abstract":"Abstract. The growth of requirements for the quality and performance of materials used for the construction of ship premises indicates the need to create new types of heat-insulating and structural and finishing products that can provide the stability of operational properties in a wide temperature range, high aesthetics and environmental safety. One of the means of providing these requirements is the use of non-flammable and non-toxic heat-insulating materials of increased strength during a fire. The processes of interaction between the components, the structure and phase composition of the obtained materials studied using complex X-ray phase, IR spectroscopic, and electron-optical methods of analysis. The main estimated quality indicators of the manufactured samples were taken: material density, thermal conductivity, ultimate strength in static bending, water absorption, also flammability and fire resistance, which determined in accordance with the current state standard and international ISO standards. The determination of the basic recipe composition of the raw mixture and the influence of technological parameters on the strength characteristics of the composite material was carried out using the method of mathematical planning of the experiment. The results obtained made it possible to fairly accurately outline the boundaries of variation of the composition of the vermiculite-silicate presscomposition and the main technological parameters. The results of the studies carried out correlate with the indicators of the physical, mechanical and technical properties of the varieties of the modified material, which makes it possible to purposefully search for the optimal composition and technological modes of manufacturing heat-insulating material for shipbuilding purposes. Using the methods of X-ray structural and electron-optical analysis, infrared spectroscopy, it has been established that as a result of heat treatment of the vermiculate-silicate presscomposition, complex physicochemical processes occur. It was found that in the system vermiculate–liquid glass –hardener, the chemical interaction of Al2O3 of vermiculate with liquid glass occurs with the formation of aluminosilicates. Additional crystallization at the vermiculite-water glass interface causes the formation of an intermediate layer of products, which prevents the occurrence of tension. The main regularities of directed synthesis in the system vermiculate–binder–hardener of neoplasms characterized by high strength and thermal stability in a wide temperature range have been studied. The optimal ratios of the main recipe components (vermiculate–binder–hardener), also a certain influence of water repellents, modifiers and reinforcing components on the processes of interaction between components, phase composition and structure of the composite have been determined.","PeriodicalId":273453,"journal":{"name":"Bulletin of Odessa State Academy of Civil Engineering and Architecture","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134491539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"INFLUENCE OF FIBER REINFORCEMENT ON CONCRETE SHRINKAGE FOR RIGID ROAD AND AIRFIELD PAVEMENT REPAIR","authors":"S. Kroviakov, V. Kryzhanovskyi","doi":"10.31650/2415-377x-2021-84-78-86","DOIUrl":"https://doi.org/10.31650/2415-377x-2021-84-78-86","url":null,"abstract":"Abstract. The influence of fiber reinforcement with steel anchor fiber on the shrinkage of modified concrete for rigid airfield pavements repair has been determined. A 2-factor experiment was carried out, in which the following composition factors were varied: the amount of hardening accelerator Sika Rapid 3 from 0 to 2.4% of the cement content (0-9.6 kg/m3); the amount of steel anchor fiber with 1 mm diameter and 50 mm length, from 0 to 100 kg/m3. For the concrete batching were used: Portland cement CEM II / AS 42.5 in the amount of 400 kg/m3, granite crushed stone 5-20 mm, quartz sand, plasticizer admixture BASF MasterGlenium SKY 608 in the amount of 1.2% by cement content. The workability of the mixtures was S2 (6-8 cm); W/C ratio depended on the concrete composition. Due to the use of superplasticizers, the W/C of all investigated mixtures was in the range of 0.309-0.343. The shrinkage of the prism specimens was recorded after 3 hours, 6 hours, 1, 2, 3 and 7 days of being in air-dry conditions. The shrinkage process does not end after 7 days of concrete hardening, however, the general nature of the influence of variable factors on its value remains. It has been established that fiber-reinforced concretes, with a fiber amount of 50 kg/m3 and with a fiber amount of 100 kg/m3, have 10-15% less shrinkage compared to unreinforced concretes. Compositions with a fiber amount of 50 kg/m3 and 100 kg/m3 have practically the same shrinkage, which is explained by an increase in W/C ratio with an increase in the amount of fiber reinforcement. The amount of hardening accelerator has a less noticeable effect on the amount of concrete shrinkage. By adding Sika Rapid 3, concrete shrinkage at the age of 7 days is reduced by 2-9%. This effect can be explained by the fact that internal stresses arising in the process of structure formation and moisture loss in concrete are contained in a more durable cement-sand matrix. The concrete shrinkage without fiber and accelerator was also measured up to the age of 98 days. It was found that the limiting shrinkage for such concrete is 2.5×10-4. The analysis of the drawn experimental-statistical model showed that with the amount of metal fiber from 60 to 90 kg/m3 and the amount of the hardening accelerator from 0.9 to 2.4%, the shrinkage of the investigated concretes is minimal (7 = 1.3×10-4). Thus, the use of fiber reinforcement with anchor steel fiber and a hardening accelerator can significantly reduce the concrete shrinkage for the rigid airfield pavements repair is important for this material.","PeriodicalId":273453,"journal":{"name":"Bulletin of Odessa State Academy of Civil Engineering and Architecture","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126742429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}