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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">sat</journal-id><journal-title-group><journal-title xml:lang="ru">НАУКА и ТЕХНИКА</journal-title><trans-title-group xml:lang="en"><trans-title>Science &amp; Technique</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2227-1031</issn><issn pub-type="epub">2414-0392</issn><publisher><publisher-name>Belarusian National Technical University</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.21122/2227-1031-2017-16-2-104-112</article-id><article-id custom-type="elpub" pub-id-type="custom">sat-993</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>СТРОИТЕЛЬСТВО</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>CIVIL AND INDUSTRIAL ENGINEERING</subject></subj-group></article-categories><title-group><article-title>ТЕХНОЛОГИЯ И ЭФФЕКТИВНОСТЬ ИСПОЛЬЗОВАНИЯ ЗОЛЫ БУРЫХ УГЛЕЙ ЛЕЛЬЧИЦКОГО МЕСТОРОЖДЕНИЯ В ЦЕМЕНТЕ И БЕТОННЫХ СМЕСЯХ</article-title><trans-title-group xml:lang="en"><trans-title>TECHNOLOGY AND EFFICIENCY IN USAGE OF BROWN COAL ASH FOR CEMENT AND CONCRETE MIXTURES AT THE LELCHITSKY DEPOSIT</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Ляхевич</surname><given-names>Г. Д.</given-names></name><name name-style="western" xml:lang="en"><surname>Lyahevich</surname><given-names>G. D.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Доктор технических наук, профессор</p><p>Адрес для переписки: Ляхевич Генрих Деонисьевич – Белорусский национальный технический университет, просп. Независимости, 150, 220013, г. Минск,   Тел.: +375 17 263-64-77   mit_ftk@bntu.by</p></bio><bio xml:lang="en"><p>Professor, PhD in Engineering</p><p>Address for correspondence: Lyahevich Genrih D. – Belarusian National Technical University, 150 Nezavisimosty Ave., 220013, Minsk, Republic of Belarus. Tel.: +375 17 263-64-77 mit_ftk@bntu.by</p></bio><email xlink:type="simple">mit_ftk@bntu.by</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Лиштван</surname><given-names>И. И.</given-names></name><name name-style="western" xml:lang="en"><surname>Lishtvan</surname><given-names>I. I.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Академик НАН Беларуси, доктор технических наук, профессор</p></bio><bio xml:lang="en"><p>Academician of NAS of Belarus, Professor, PhD in Engineering</p></bio><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Ляхевич</surname><given-names>А. Г.</given-names></name><name name-style="western" xml:lang="en"><surname>Lyahevich</surname><given-names>A. G.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Кандидат экономических наук, доцент</p></bio><bio xml:lang="en"><p>Associate Professor, PhD in Economics</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Дударчик</surname><given-names>В. М.</given-names></name><name name-style="western" xml:lang="en"><surname>Dudarchik</surname><given-names>V. M.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Кандидат технических наук</p></bio><bio xml:lang="en"><p>PhD in Engineering</p></bio><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Крайко</surname><given-names>В. М.</given-names></name><name name-style="western" xml:lang="en"><surname>Kraiko</surname><given-names>V. M.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Кандидат технических наук</p></bio><bio xml:lang="en"><p>PhD in Engineering</p></bio><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Звонник</surname><given-names>С. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Zvonnik</surname><given-names>S. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Аспирант</p></bio><bio xml:lang="en"><p>Graduate student</p></bio><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Белорусский национальный технический университет</institution><country>Беларусь</country></aff><aff xml:lang="en"><institution>Belarusian National Technical University</institution><country>Belarus</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>Институт природопользования НАН Беларуси</institution><country>Беларусь</country></aff><aff xml:lang="en"><institution>Institute for Nature Management of NAS of Belarus</institution><country>Belarus</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2017</year></pub-date><pub-date pub-type="epub"><day>29</day><month>03</month><year>2017</year></pub-date><volume>16</volume><issue>2</issue><fpage>104</fpage><lpage>112</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Ляхевич Г.Д., Лиштван И.И., Ляхевич А.Г., Дударчик В.М., Крайко В.М., Звонник С.А., 2017</copyright-statement><copyright-year>2017</copyright-year><copyright-holder xml:lang="ru">Ляхевич Г.Д., Лиштван И.И., Ляхевич А.Г., Дударчик В.М., Крайко В.М., Звонник С.А.</copyright-holder><copyright-holder xml:lang="en">Lyahevich G.D., Lishtvan I.I., Lyahevich A.G., Dudarchik V.M., Kraiko V.M., Zvonnik S.A.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://sat.bntu.by/jour/article/view/993">https://sat.bntu.by/jour/article/view/993</self-uri><abstract><p>В современных представлениях о роли высокодисперсных добавок в бетонных смесях отмечается положительное влияние оптимального количества золы от сжигания твердого топлива на структуру и физико-механические характеристики цементных композиций: упрочнение контактной зоны между цементным камнем и заполнителями с образованием кластеров «вяжущее – наполнитель» за счет высокой поверхностной энергии частиц наполнителя; снижение общей пористости цементного камня в бетоне при увеличении объемной концентрации и дисперсности наполнителя; связывание гидроксида кальция аморфизованным кремнеземом пуццолановых наполнителей; повышение пуццоланической активности наполнителя при его тонком измельчении и др. Экспериментальными исследованиями установлено, что использование в сырьевых смесях портландцементного клинкера образцов золы от сжигания бурых углей Лельчицкого месторождения способствовало увеличению жизнеспособности и активности цемента. Получены образцы бетона с улучшенными физико-механическими свойствами благодаря введению в их состав 2–14 % (от массы цемента) золы от сжигания бурого угля и 1,6–2,1 % натриевой соли продукта конденсации сульфооксидата ароматических углеводородов с формальдегидом. Эффективность выполненной работы подтвердилась решением вопросов увеличения жизнеспособности цементного теста, активности цемента, прочности бетона. Не менее важной решаемой проблемой является защита окружающей среды от загрязнений золой от сжигания высокозольных бурых углей. </p></abstract><trans-abstract xml:lang="en"><p>Modern visions on the role of high-dispersity additives in concrete mixtures reflect a positive effect of optimal amount of ash left after combustion of solid fuel on structure and physico-mechanical characteristics of cement compositions: hardening of contact zone between cement stone and aggregates with formation of “binder – aggregate” clusters due to high surface energy of aggregate particles; reduction of total cement stone porosity in concrete while increasing volumetric concentration and aggregate dispersion; binding of calcium hydroxide by amorphized silicon of pozzolanic aggregates; increase in pozzolanic aggregate activity with its fine grinding, etc. Experimental investigations have ascertained that usage of portland cement clinker ash samples left after brown coal burning at the Lelchitsky deposit contributed to an increase of cement working life and activity. Concrete samples have been obtained that have improved physico-mechanical properties owing to introduction the following components in their composition: 2–14 % (of cement mass) of ash left after brown coal burning and 1.6–2.1 % of sodium salt that is a condensation product of sulfur oxidate in aromatic hydrocarbons with formaldehyde. Efficiency of the executed work has been proved by solution of the problems pertaining to an increase of neat cement working life, cement activity, concrete strength. The paper also considers no less important problem concerning protection of the environment from contamination with ash left after burning of high-ash brown coal. </p></trans-abstract><kwd-group xml:lang="ru"><kwd>технология</kwd><kwd>эффективность</kwd><kwd>золы</kwd><kwd>бурые угли</kwd><kwd>Лельчицкое месторождение</kwd><kwd>цемент</kwd><kwd>бетонные смеси</kwd></kwd-group><kwd-group xml:lang="en"><kwd>technology</kwd><kwd>efficiency</kwd><kwd>ash</kwd><kwd>brown coal</kwd><kwd>Lelchitsky deposit</kwd><kwd>cement</kwd><kwd>concrete mixtures</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Геополимербетон с золой уноса [Электронный ресурс] // Строительный мир. Режим доступа: http://www. stroinauka.ru/dl9dr5492m2.html. Дата доступа: 11.01.2006.</mixed-citation><mixed-citation xml:lang="en">Geopolymer Concrete with Pulverized Fuel Ash. Stroitelny Mir [Construction World]. Available at: http://www.stroi nauka.ru/dl9dr5492m2.html. (Accessed 11 January 2006) (in Russian).</mixed-citation></citation-alternatives></ref><ref id="cit2"><label>2</label><citation-alternatives><mixed-citation xml:lang="ru">Волженский, А. В. Применение зол и топливных шлаков в производстве строительных материалов / А. В. Волженский, И. А. Иванов, Б. Н. Виноградов. М.: Стройиздат, 1984. 247 с.</mixed-citation><mixed-citation xml:lang="en">Volzhensky A. V., Ivanov I. A., Vinogradov B. N. (1984) Application of Ash and Furnace Clinker for Production of Construction Materials. Moscow, Stroyizdat. 247 (in Russian).</mixed-citation></citation-alternatives></ref><ref id="cit3"><label>3</label><citation-alternatives><mixed-citation xml:lang="ru">Рыбьев, И. А. Создание строительных материалов с заданными свойствами / И. А. Рыбьев, А. А. Жданов // Известия вузов. Строительство. 2003. № 3. С. 45–48.</mixed-citation><mixed-citation xml:lang="en">Rybiev I. A., Zhdanov A. A. (2003) Development of Construction Materials with Prescribed Properties. Izvestia Vuzov. Stroitelstvo [News of Higher Education Institutions. Construction], (3), 45–48 (in Russian).</mixed-citation></citation-alternatives></ref><ref id="cit4"><label>4</label><citation-alternatives><mixed-citation xml:lang="ru">Баженов, Ю. М. Развитие теории формирования структуры и свойств бетонов с техногенными отходами / Ю. М. Баженов, Л. А. Алимов, В. В. Воронин // Известия вузов. Строительство. 1996. № 7. С. 55–58.</mixed-citation><mixed-citation xml:lang="en">Bazhenov Yu. M., Alimov L. A., Voronin V. V. (1996) Development of Theory for Formation of Structure and Properties of Concrete with Technogenic Waste. Izvestia Vuzov. Stroitelstvo [News of Higher Education Institutions. Construction], (7), 55–58 (in Russian).</mixed-citation></citation-alternatives></ref><ref id="cit5"><label>5</label><citation-alternatives><mixed-citation xml:lang="ru">Власов, В. К. Закономерности оптимизации состава бетона с дисперсными минеральными добавками / В. К. Власов // Бетон и железобетон. 1993. № 4. С. 10–12.</mixed-citation><mixed-citation xml:lang="en">Vlasov V. K. (1993) Regularities on Optimization of Composition for Concrete with Disperse Mineral Additives. Beton i Zhelezobeton [Concrete and Reinforced Concrete], (4), 10–12 (in Russian).</mixed-citation></citation-alternatives></ref><ref id="cit6"><label>6</label><citation-alternatives><mixed-citation xml:lang="ru">Власов, В. К. Механизм повышения прочности бетона при введении микронаполнителя / В. К. Власов // Бетон и железобетон. 1988. № 10. С. 9–11.</mixed-citation><mixed-citation xml:lang="en">Vlasov V. K. (1988) Mechanism for Improving Concrete Strength While Introducing Micro-Filler. Beton i Zhelezobeton [Concrete and Reinforced Concrete], (10), 9–11 (in Russian).</mixed-citation></citation-alternatives></ref><ref id="cit7"><label>7</label><citation-alternatives><mixed-citation xml:lang="ru">Высоцкий, С. А. Минеральные добавки для бетонов / С. А Высоцкий // Бетон и железобетон. 1994. № 2. С. 7–10.</mixed-citation><mixed-citation xml:lang="en">Vysotsky S. A. (1994) Mineral Additives for Concrete. Beton i Zhelezobeton [Concrete and Reinforced Concrete], (2), 7–10 (in Russian).</mixed-citation></citation-alternatives></ref><ref id="cit8"><label>8</label><citation-alternatives><mixed-citation xml:lang="ru">Bastian, S. Wodoszczelnosc Betonow z Popiolow Lotnych / S. Bastian // Przeglad Budowlany. 1971. No 6. P. 319–329.</mixed-citation><mixed-citation xml:lang="en">Bastian S. (1971) Wodoszczelnosc Betonow z Popiolow Lotnych. Przeglad Budowlany, (6), 319–329 (in Polish).</mixed-citation></citation-alternatives></ref><ref id="cit9"><label>9</label><citation-alternatives><mixed-citation xml:lang="ru">Berry, E. E. Fly Ash for Use in Concrete – a Critical Review / E. E. Berry, V. M. Malhotra // ACI Journal. 1980. Vol. 77, No 2. P. 59–73.</mixed-citation><mixed-citation xml:lang="en">Berry E. E., Malhotra V. M. (1980) Fly Ash for Use in Concrete – a Critical Review. Journal of the American Concrete Institute, 77 (2), 59–73.</mixed-citation></citation-alternatives></ref><ref id="cit10"><label>10</label><citation-alternatives><mixed-citation xml:lang="ru">Composite Cementless Binder from Mechanical Active Industrial Wastes Text / Yu. M. Bazhenov [et al.] // Proceedings of the 5 International Symposium on the Cement and Concrete Shanghai, China, 2002, Oct. 28–Nov. 1. P. 832–840.</mixed-citation><mixed-citation xml:lang="en">Bazhenov Yu. M., Magdejev U. Kh, Pavlenko S. I., Kulagin N. M., Aksenov A. V., Tkachenko V. V., Dobretsov N. L., Lyakhov N. Z., Avvakumov, E. G. (2002) Composite Cementless Binder from Mechanical Active Industrial Wastes Text. Proceedings of the 5 International Symposium on the Cement and Concrete Shanghai, China, Oct. 28.–Nov. 1, 832–840.</mixed-citation></citation-alternatives></ref><ref id="cit11"><label>11</label><citation-alternatives><mixed-citation xml:lang="ru">Feng, Nai-Qian. High-Strength and Flowing Concrete with a Zeoiitic Mineral Admixture / Nai-Qian Feng, Li GuiZhi, Zang Xuan-Wu // Cements, Concrete and Aggregates. 1990. Vol. 12, No 2. P. 61–69.</mixed-citation><mixed-citation xml:lang="en">Feng Nai-Qian, Li Gui-Zhi, Zang Xuan-Wu (1990) HighStrength and Flowing Concrete with a Zeoiitic Mineral Admixture. Cements, Concrete and Aggregates, 12 (2), 61–69. DOI: 10.1520/CCA10273J.</mixed-citation></citation-alternatives></ref><ref id="cit12"><label>12</label><citation-alternatives><mixed-citation xml:lang="ru">Larbi, J. A. The Chemistry of the Pole Fluid of Silica Fume-Blended Cement Systems / J. A. Larbi, J. M. Bijen //Cem. and Concr. Res. 1990. Vol. 20, No 4. P. 506–516.</mixed-citation><mixed-citation xml:lang="en">Larbi J. A., Bijen J. M. (1990) The Chemistry of the Pole Fluid of Silica Fume-Blended Cement Systems. Cement and Concrete Research, 20 (4), 506–516. DOI:10.1016/ 0008-8846(90)90095-F.</mixed-citation></citation-alternatives></ref><ref id="cit13"><label>13</label><citation-alternatives><mixed-citation xml:lang="ru">Malhotra, V. M. High-Performance, High-Volume Fly Ash Concrete: Materials, Mixture Proportioning, Properties, Construction Practice and Case Histories / V. M. Malhotra, P. K. Mehta. Ottawa, Canada: Printed by Marguardt Printing Ltd., 2002. P. 101.</mixed-citation><mixed-citation xml:lang="en">Malhotra V. M., Mehta P. K. (2002) High-Performance, High-Volume Fly Ash Concrete: Materials, Mixture Proportioning, Properties, Construction Practice and Case Histories. Ottawa, Canada: Printed by Marguardt Printing Ltd. 101.</mixed-citation></citation-alternatives></ref><ref id="cit14"><label>14</label><citation-alternatives><mixed-citation xml:lang="ru">Matsufuji, Y. Прочностные характеристики растворов, содержащих сверхтонкие частицы / Y. Matsufuji, H. Kohhata, S. Harada // Semento Konkurito Ronbunshu = = CAJ Proc. Cem. and Concr. 1991. No 45. Р. 264–269.</mixed-citation><mixed-citation xml:lang="en">Matsufuji Y., Kohhata H., Harada S. (1991) Strength Characteristics of Solutions Containing Superfineparticles. Semento Konkurito Ronbunshu = CAJ Proc. Cem. and Concr., 45, 264–269.</mixed-citation></citation-alternatives></ref><ref id="cit15"><label>15</label><citation-alternatives><mixed-citation xml:lang="ru">Sarkar Shondeep, L. Microstrukture of a Very Low Water/Cement Silica Fume Concrete / L. Sarkar Shendeep // Microscope. 1990. Vol. 38, No 2. P. 141–152.</mixed-citation><mixed-citation xml:lang="en">Sarkar Shondeep L. (1990) Microstrukture of a Very Low Water/Cement Silica Fume Concrete. Microscope, 38 (2), 141–152.</mixed-citation></citation-alternatives></ref><ref id="cit16"><label>16</label><citation-alternatives><mixed-citation xml:lang="ru">Xu, Ziyi. Research on Super Fine Fly Ash and its Activity / Ziyi Xu, Liu Linzhy // Proc. Beijing Int. Symp. Cem. and Concr., Beijing, May 14–17, 1985. 1985. Vol. 1. P. 493–507.</mixed-citation><mixed-citation xml:lang="en">Xu Ziyi, Liu Linzhy (1985) Research on Super Fine Fly Ash and its Activity. Proc. Beijing Int. Symp. Cem. and Concr., Beijing, May 14–17, 1, 493–507.</mixed-citation></citation-alternatives></ref><ref id="cit17"><label>17</label><citation-alternatives><mixed-citation xml:lang="ru">Бабков, В. В. Аспекты формирования высокопрочных и долговечных цементных связок в технологии бетонов / В. В. Бабков, И. Ш. Каримов, П. Г. Комохов // Известия вузов. Строительство. 1996. № 4. С. 41–48.</mixed-citation><mixed-citation xml:lang="en">Babkov V. V., Karimov I. Sh., Komokhov P. G. (1996) Aspects for Formation of Highly-Strong and Durable Cement Binding Material in Concrete Technology. Izvestia Vuzov. Stroitelstvo [News of Higher Education Institutions. Construction], (4), 41–48 (in Russian).</mixed-citation></citation-alternatives></ref><ref id="cit18"><label>18</label><citation-alternatives><mixed-citation xml:lang="ru">Зоткин, А. Г. Микронаполняющий эффект минеральных добавок в бетоне / А. Г. Зоткин // Бетон и железобетон. 1994. № 3. С. 7–9.</mixed-citation><mixed-citation xml:lang="en">Zotkin A. G. (1994) Micro-Filling Effect of Mineral Additives in Concrete. Beton i Zhelezobeton [Concrete and Reinforced Concrete], (3), 7–9 (in Russian).</mixed-citation></citation-alternatives></ref><ref id="cit19"><label>19</label><citation-alternatives><mixed-citation xml:lang="ru">Каприелов, С. С. Общие закономерности формирования структуры цементного камня и бетона с добавкой ультрадисперсных материалов / С. С. Каприелов // Бетон и железобетон. 1995. № 6. С. 16–20.</mixed-citation><mixed-citation xml:lang="en">Kaprielov S. S. (1995) General Regularities in Formation Cement Stone Structure and Concrete with Additive of Ultra-Disperse Materials. Beton i Zhelezobeton [Concrete], (6), 16–20 (in Russian).</mixed-citation></citation-alternatives></ref><ref id="cit20"><label>20</label><citation-alternatives><mixed-citation xml:lang="ru">Красный, И. М. О механизме повышения прочности бетона при введении микронаполнителей / И. М. Красный // Бетон и железобетон. 1987. № 5. С. 10–11.</mixed-citation><mixed-citation xml:lang="en">Krasny I. M. (1987) On Mechanism for Improving Concrete Strength while Introducing Micro-Fillers. Beton i Zhelezobeton [Concrete and Reinforced Concrete], (5), 10–11 (in Russian).</mixed-citation></citation-alternatives></ref><ref id="cit21"><label>21</label><citation-alternatives><mixed-citation xml:lang="ru">Леонович, И. И. Испытание дорожно-строительных материалов / И. И. Леонович, В. А. Стрижевский, К. Ф. Шумчик. Минск: Высш. шк., 1991. 233 с.</mixed-citation><mixed-citation xml:lang="en">Leonovich I. I., Strizhevsky V. A., Shumchik K. F. (1991) Testing of Road-Construction Materials. Minsk, Vysshaya Shkola. 233 (in Russian).</mixed-citation></citation-alternatives></ref><ref id="cit22"><label>22</label><citation-alternatives><mixed-citation xml:lang="ru">Горшков, В. С. Методы физико-химического анализа вяжущих веществ / В. С. Горшков, В. В. Тимашев, В. Г. Савельев. М.: Высш. шк., 1981. 335 с.</mixed-citation><mixed-citation xml:lang="en">Gorshkov V. S., Timashev V. V., Saveliev V. G. (1981) Methods for Physical and Chemical Analysis of Binders. Moscow, Vysshaya Shkola. 335 (in Russian).</mixed-citation></citation-alternatives></ref></ref-list><fn-group><fn fn-type="conflict"><p>The authors declare that there are no conflicts of interest present.</p></fn></fn-group></back></article>
