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Ключові слова: search.filters.subject.кафедра технології будівельних конструкцій і виробів,equals Дата початку: search.filters.dateIssued.min.2018 Кінцева дата: search.filters.dateIssued.max.2019

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Зараз показуємо 1 - 10 з 21
  • Документ
    Production of modified basalt fibre for heat-insulating products manufacturing
    (IOP Publishing, 2019) Gots, V. I.; Berdnyk, O.Y.; Rogozina, N. O.; Maystrenko, А. А.
    As a result of the research flexible heat-insulating materials were developed based on basalt fiber with increased effectiveness, which can be achieved due to directed fiber microstructure forming through fusion modification. It is known that chemical composition of initial fusion not identically influences on physical and chemical and mechanical properties of basaltic fibres. Structural descriptions of fusion and basaltic fibre got from him appear main factors the nearer, than high speed of cooling. This index mainly depends on such constituents: а) ambient temperatures; b) coefficient of heat conducting; c) heat conducting of fusion; d) areas of surface. By researches influence of temperature of basaltic fusion was shown on the structure of fibres. Structural characteristics of the basalt fiber (number of active zones, coefficient of its distribution on the basalt fiber surface, as well as a correlation of three groups of active zones) depend on rheological properties of basal fusion, speed of drawing through the die plate and cooling speed.
  • Документ
    The influence of technological factors on the properties of basalt fiber when used in the manufacture of flexible heat and sound insulating products
    (Proceedings of the 3rd Annual Conference “Technology transfer: fundamental principle and innovative technical solutions”. Tallin, Estonia, 2019) Berdnyk, Oksana
    Analysis of energy efficiency and operational safety of technological equipment of industrial enterprises, engineering networks, buildings and structures, building structures in many sectors of the economy, including the housing and industrial sectors, causes interest in the use of high-tech, environmentally friendly heat and sound insulation materials with enhanced performance properties. One of the relevant representatives of these materials is basalt fibers and their use as raw materials in the production of flexible heat and sound insulating products. It is known that the chemical composition of the initial melt equally affects the physicochemical and mechanical properties of basalt fibers. The main influence factors, including the chemical composition, are the thermal past of the melt, the method for producing basalt fiber and the conditions for the formation of its structure. These factors determine the structural characteristics of the fiber and, as a consequence, its physicochemical characteristics. The degree of fiber strength is directly determined by its chemical composition and production method. The greatest strength of the fiber is obtained by ensuring the perfect fiber structure in the absence of ruptures of siliceous chains
  • Документ
    INVESTIGATION OF PROPERTIES OF MODIFIED BASALT FIBERS
    (2018) Gots, Volodymyr; Palchyk, Petr; Berdnyk, Oksana
    Thermophysical, physical-mechanical and acoustic characteristics of a rough continuous basalt fiber under the influence of operating factors and a corrosive environment are studied. It is shown that the production of protective materials with high thermophysical and acoustic properties is possible when creating a porous system with a known texture characteristic of pores of different classes, purposes and connections. An influence of the porous system of rough continuous basalt fiber on the operational properties of flexible heat and sound insulation products and materials is studied. The requirements of normative documents on thermal protection of buildings and structures have caused a constant tendency from the creation of new materials that ensure reliable operation of structures and equipment in the conditions of intensive influence of destructive factors of external influence. This led to an increase in requirements for walling wall materials that are used to fill openings in frame construction, or as an independent structural and thermal insulation material when building buildings with load-bearing walls. They are presented with a set of requirements that combines: physical and mechanical, chemical, hygienic, thermophysical, decorative and finishing, and other properties of the material. In this connection, there is a need to create materials that, having a small average density and high strength, are able to withstand the temperature loads, and the influence of an aggressive environment. It is determined that the performance characteristics of flexible heat and sound insulation materials are directly proportional to the degree of porosity of the composite materials and their structural characteristics. It is shown that the increase in the operating temperature of these materials, sound and thermal resistance is determined by the chemical and mineralogical composition of the initial materials and their structural characteristics. The influence of the mechanism of selective leaching of coarse continuous basalt fibers on their texture characteristics and the operating temperature zone is studied. The resulting material is produced from environmentally friendly raw materials using a one-stage technology without harmful effects on the environment and, unlike thermal insulation materials based on polymers or asbestos, has no harmful effect on the human body, meets the requirements of the European Union for the protection of the environment and sanitary and hygienic standards.
  • Документ
    Development of decisions for alkali-activated cements proper deformations control
    (ПП «Технологічний Центр», 2019-11) Krivenko, P.; Gots, V.; Petropavlovskyi, O.; Rudenko, I.; Konstantynovskyi, O.; Kovalchuk, A.
    The relevance of using cements containing mineral admixtures of both natural and artificial origin is determined by compliance with current trends in sustainable mankind development in terms of efficient consumption of raw materials and energy and responsible attitude to the environment. From the environmental point of view, partial replacement of cement clinker with mineral admixtures contributes to the reduction of CO2 emissions. In addition, materials based on such cements are characterized by high quality, functionality and durability. For example, efficiency of using blast furnace slag, zeolite and limestone in composite eco-cements with high initial strength has been demonstrated [1].
  • Документ
    Development of solutions concerning regulation of proper deformations in alkali-activated cements
    (ПП «Технологічний Центр», 2019-11) Krivenko, P.; Gots, V.; Petropavlovskyi, O.; Rudenko, I.; Konstantynovskyi, O.; Kovalchuk, A.
    The essence of the problem related to proper deformations in alkali-activated cements (AAC) complicated with high content of gel-like hydrate formations was analyzed. Cement types diametrically opposite in their compositions and, accordingly, in the content of gel phases during hydration, that is, the alkali-acti�- vated portland cement (AAPC) and alkali-activated slag cement (AASC) were taken for consideration. Approaches to formation of an effective structure of artificial stone counteracting shrinkage deformation by means of interference in structure formation when using complexes of mineral and organic compounds were proposed. Such compounds in composition of complex organomineral admixtures jointly influence intensification of crystallization processes and formation of an effective pore structure and morphology of hydrate phases while reducing water content in artificial stone. Salt electrolytes of various anionic types and anion-active surface-active substances were considered as ingredients of the proposed complex modifying admixtures. It has been found that the “salt electrolyte–surfactant” system is the most effective for AAPC modification. It was shown that modification of AAPC with this complex admixture based on NaNO3 reduced shrinkage from 0.406 to 0.017 mm/m. Instead, the use of Na2SO4 provided AAC of this type with a capacity of expansion up to 0.062 mm/m. It was shown that the effect of compensated shrinkage of modified AAPC is associated with a higher crystallization of low-basicity hydrosilicates (CSH(B)) and calcium hydroaluminates (CaO∙Al2O3∙10H2O). An additional effect is associated with formation of sulfate-containing sodium-calcium hydroaluminate (for the Na2SO4-based system) and crystalline calcium hydronitroaluminate (for the NaNO3-based system) with a corresponding microstructure stress. For further development, a complex admixture of “Portland cement clinker–salt electrolyte–surfactant” system was proposed for AASC modification. It provided shrinkage reduction from 0.984 mm/m to 0.683 mm/m. Minimization of the modified AASC shrinkage was explained by formation of sodium hydroalumosilicate of gmelinite type ((Na2Ca)∙Al2∙Si4∙O12∙6H2O) with a high degree of crystallization along with low-basicity calcium hydrosilicates. It was noted that the cement stone structure is characterized by high density, uniformity, and consolidation of hydrate formations.
  • Документ
    Мікропориста структура грубих базальтових волокон і їх структурні характеристики
    (ОДАБА, 2019) Гоц, В. І.; Пальчик, П. П.; Майстренко, А. А.; Бердник, О. Ю.
    Вимоги нормативних документів по теплозахисту будівель і споруд обумовили сталу тенденцію по створенню нових матеріалів , які забезпечують роботу конструкцій і обладнання в умовах інтенсивного впливу деструктивних факторів зовнішнього впливу.
  • Документ
    Alkali activated portland cement with adjustable proper deformations for anchoring application
    (IOP Publishing Ltd, 2019) Krivenko, P. V.; Rudenko, I. I.; Petropavlovskyi, O. M.; Konstantynovskyi, O. P.; Kovalchuk, A. V.
    The application of alkali-activated Portland cement (hereinafter AAPC) for anchoring grouts was investigated with obtaining of non-shrinking high performance cementing systems. The AAPC system “ordinary Portland cement clinker – sodium metasilicate” was modified by the complexes of mineral and organic compounds to ensure specified properties of anchoring grouts. It was revealed that the most effective multifunctional additives are represented by the system “salt-electrolyte – surfactant”. Alongside with slowing down of AAPC paste setting time, the effect of compensated shrinkage of AAPC mortar, i.e. expansion within 0.062 mm/m and slight shrinkage within 0.017 mm/m, was ensured when Na2SO4 and NaNO3 were used in the mentioned system respectively. The effect of compensated shrinkage is explained by greater crystallization of ydrosilicates and hydroaluminates, additional formation of sulfate-containing sodium-calcium hydroaluminate (for Na2SO4-based system) and crystalline calcium hydronitroaluminate (for NaNO3-based system). The advantages of the modified AAPC for anchoring application are indicated in thepaper.
  • Документ
    Вплив органо-мінеральних комплексів на міцність і власні деформації шлаколужних цементів
    (ОДАБА, 2019) Кривенко, П. В.; Петропавловський, О. М.; Руденко, І. І.; Константиновський, О. П.
    Запропоновано комплексну органо-мінеральну добавку складу «портландцементний клінкер – електроліт – поверхнево-активна речовина», використання якої в шлаколужному цементі забезпечує сповільнення строків тужавлення, підвищення показників міцності і практично відсутність усадки (0,062 мм/м). Показано особливості роботи портландцементного клінкеру у лужному середовищі, вплив добавок солей різного аніонного типу та луговміщуючих аніоноактивних ПАР на водопотребу, синтез міцності та власні деформації при гідратації та формування структури штучного каменя на його основі. Відмічена перспективність запровадження таких органо-мінеральних комплексів в якості додаткових компонентів шлаколужних цементів для регулювання їх технологічними і фізико-механічними властивостями, у т.ч. для зменшення усадки цементного каменя
  • Документ
    The efficiency of plasticizing surfactants in alkali-activated cement mortars and concretes
    (EDP Sciences, 2018) Runova, Raisa; Gots, Volodymyr; Rudenko, Igor; Konstantynovskyi, Oleksandr; Lastivka, Oles’
    Functionality of mortar and concrete mixes is regulated by surfactants, which act as plasticizers. The molecular structure of these admixtures can be changed during hydration of alkali-activated cements (AAC). The objective was to determine the chemical nature of plasticizers effective for property modification of mortars and concretes based on AACs with changing content of granulated blast furnace slag from 0 to 100 %. The admixtures without ester links become more effective than polyesters when content of alkaline component increase. The admixtures effective in high alkaline medium were used in dry mixes for anchoring (consistency of mortar 150 mm by Vicat cone; 1 d tensile strength in bending / compressive strength of mortar 6.6 /30.6 MPа) and in readymixed concretes (consistency class changed from S1 to S3, S4 with consistency safety during 60 min; 3 d compressive strength of modified concrete was not less than the reference one without admixtures).
  • Документ
    Вплив органо-мінеральних комплексних добавок на властивості анкерних розчинів на основі лужного портландцементу
    (ТОВ "Видавництво "БАРМИ", 2019) Кривенко, П. В.; Петропавловський, О. М.; Руденко, І. І.
    Розглянуто напрямок ефективного використання лужних портландцементів в якості основи анкерних розчинів з точки зору отримання безусадочних цементуючих систем та забезпечення їх високих фізико-механічних властивостей. Досліджено вплив комплексів мінеральних і органічних сполук на технологічні та фізико-механічні властивості лужного портландцементу системи «портландцементний клінкер - метасилікат натрію» з формуванням ефективної структури штучного каменя, протидіючою деформаціям усадки. За комплексним впливом виявлено, що найбільш ефективні органо-мінеральні багатофункціональні добавки представлені системою «сіль-електроліт – поверхнево-активна речовина». При необхідному сповільненні строків тужавлення цементу забезпечується ефект компенсованої усадки - розширення в межах 0,062 мм/м або незначної усадки в межах 0,017 мм/м при використанні в системі Na2SO4 і NaNO3 відповідно. За допомогою методів фізико- хімічного аналізу ефект компенсованої усадки пояснено більшою кристалізацією гідросилікатів та гідроалюмінатів з утворенням додатково сульфатвміщуючого натрієво-кальцієвого гідроалюмінату (для системи на основі Na2SO4) або з формуванням кристалічного гідронітроалюмінату кальцію (для системи на основі NaNO3) з відповідним напруженням структури штучного каменю. Вказано на перспективність використання лужних портландцементів, модифікованих запропонованими органо- мінеральними комплексами, в якості основи для анкерних розчинів.