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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">vestniktgasu</journal-id><journal-title-group><journal-title xml:lang="ru">Вестник Томского государственного архитектурно-строительного университета</journal-title><trans-title-group xml:lang="en"><trans-title>Vestnik Tomskogo gosudarstvennogo arkhitekturno-stroitel'nogo universiteta. JOURNAL of Construction and Architecture</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">1607-1859</issn><issn pub-type="epub">2310-0044</issn><publisher><publisher-name>Tomsk State University of Architecture and Building</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.31675/1607-1859-2020-22-1-92-105</article-id><article-id custom-type="elpub" pub-id-type="custom">vestniktgasu-747</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>СТРОИТЕЛЬНЫЕ КОНСТРУКЦИИ, ЗДАНИЯ И СООРУЖЕНИЯ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>BUILDING AND CONSTRUCTION</subject></subj-group></article-categories><title-group><article-title>КРИТЕРИЙ ОЦЕНКИ ОПТИМАЛЬНЫХ РЕШЕНИЙ ПРИ ФОРМИРОВАНИИ КУСОЧНО-ПОСТОЯННЫХ УЧАСТКОВ ПОЛКИ СТЕРЖНЕЙ ДВУТАВРОВОГО ПОПЕРЕЧНОГО СЕЧЕНИЯ ПРИ ОГРАНИЧЕНИЯХ ПО УСТОЙЧИВОСТИ ИЛИ НА ВЕЛИЧИНУ ПЕРВОЙ ЧАСТОТЫ СОБСТВЕННЫХ КОЛЕБАНИЙ</article-title><trans-title-group xml:lang="en"><trans-title>ASSESSMENT CRITERION FOR OPTIMUM DESIGN SOLUTIONS OF PIECEWISE CONSTANT SECTIONS IN RODS OF I-SHAPED CROSS-SECTION WITH STABILITY OR FIRST EIGEN-FREQUENCY LIMITS</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>Ляхович</surname><given-names>Л. C.</given-names></name><name name-style="western" xml:lang="en"><surname>Lyakhovich</surname><given-names>L. S.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Ляхович Леонид Семенович, докт. техн. наук, профессор, академик Российской академии архитектуры и строительных наук,</p><p>634003, г. Томск, пл. Соляная, 2</p></bio><bio xml:lang="en"><p>Leonid S. Lyakhovich, DSc, Professor, Academy Fellow of the Russian Academy of Architecture and Construction Sciences, Department of Structural Mechanics</p><p>2, Solyanaya Sq., 634003, Tomsk</p></bio><email xlink:type="simple">lls@tsuab.ru</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>Акимов</surname><given-names>П. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Akimov</surname><given-names>P. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Акимов Павел Алексеевич, докт. техн. наук, профессор, академик Российской академии архитектуры и строительных наук,</p><p>634003, г. Томск, пл. Соляная, 2</p><p>главный ученый секретарь </p><p>107031, г. Москва, ул. Большая Дмитровка, 24, стр. 1 </p></bio><bio xml:lang="en"><p>Pavel A. Akimov, DSc, Professor, Chief Academic Secretary, Academy Fellow</p><p>Professor, Department of Structural Mechanics </p><p>2, Solyanaya Sq., 634003, Tomsk</p></bio><email xlink:type="simple">akimov@raasn.ru</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Тухфатуллин</surname><given-names>Б. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Tukhfatullin</surname><given-names>B. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Тухфатуллин Борис Ахатович, канд. техн. наук, доцент </p><p>634003, г. Томск, пл. Соляная, 2</p></bio><bio xml:lang="en"><p>Boris A. Tukhfatullin, PhD, A/Professor, Department of Structural Mechanics</p><p>2, Solyanaya Sq., 634003, Tomsk</p></bio><email xlink:type="simple">bat9203@gmail.com</email><xref ref-type="aff" rid="aff-3"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Томский государственный архитектурностроительный университет,</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Tomsk State University of Architecture and Building</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>Томский государственный архитектурностроительный университет; президиум Российской академии архитектуры и строительных наук</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Russian Academy of Architecture and Construction Sciences; &#13;
Tomsk State University of Architecture and Building</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-3"><aff xml:lang="ru"><institution>Томский государственный архитектурно-строительный университет</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Tomsk State University of Architecture and Building</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2020</year></pub-date><pub-date pub-type="epub"><day>28</day><month>02</month><year>2020</year></pub-date><volume>22</volume><issue>1</issue><fpage>92</fpage><lpage>105</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Ляхович Л.C., Акимов П.А., Тухфатуллин Б.А., 2020</copyright-statement><copyright-year>2020</copyright-year><copyright-holder xml:lang="ru">Ляхович Л.C., Акимов П.А., Тухфатуллин Б.А.</copyright-holder><copyright-holder xml:lang="en">Lyakhovich L.S., Akimov P.A., Tukhfatullin B.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://vestnik.tsuab.ru/jour/article/view/747">https://vestnik.tsuab.ru/jour/article/view/747</self-uri><abstract><p>В опубликованных работах авторов были рассмотрены некоторые особые свойства соответствующих оптимальных систем и сформулированы критерии, позволяющие адекватно оценить близость оптимальных решений к минимально материалоѐмкому. В частности были представлены такого рода критерии для стержней с двутавровым поперечным сечением при заданных ограничениях по устойчивости или на величину первой частоты собственных колебаний.</p><p>Указанные критерии можно использовать при решении задачи оптимизации, когда поперечные сечения стержня непрерывно изменяются по его длине. Определяемые таким образом оптимальные решения могут рассматриваться как идеализированный объект в смысле предельного. Данная функция оптимального проекта дает возможность оценивать реальное конструкторское решение на основе критерия его близости к предельному (например, по материалоѐмкости).</p><p>Такого рода оптимальный проект также может использоваться и как определенный ориентир при реальном проектировании, например, в рамках поэтапного процесса перехода от идеального объекта к реальному.</p><p>Следует отметить, что при этом на каждом этапе имеется возможность оценить изменения показателя оптимальности объекта по сравнению с начальным и с идеализированным решениями. В частности, один из вариантов соответствующего процесса предусматривает замену непрерывного изменения размеров поперечных сечений стержня по его длине соответствующими кусочно-постоянными участками. Границы этих участков могут выбираться на основе идеального объекта, а размеры поперечных сечений определяться с использованием одного из методов оптимизации. В настоящей статье представлены критерии, дающие возможность достоверно и надежно оценить момент окончания процесса подобной оптимизации.</p></abstract><trans-abstract xml:lang="en"><p>Specific properties of optimum systems have been already considered in previous research. Moreover, the criteria were proposed for a correct assessment of proximity of optimum to minimum material consumption. In particular, the criteria are proposed for rods of rectangular crosssection with stability or first eigen-frequency limits. These criteria can be used for problem optimization, when the rod cross-sections continuously change longitudinally. The obtained optimum solutions can be considered as a perfect limited object. This optimum project function allows researcher to assess the real design solution using the proximity limit criterion (for example, material consumption limit). This kind of optimum design can also be used as a guideline for real design in terms of a stage-by-stage process of transition from a perfect to real object. In this case, it is possible to assess changes in the object optimality at each stage as compared to the initial and idealized solutions. In particular, one of the variants of the process includes replacing the rod with continuous longitudinally varying cross-sections by a rod with piecewise constant sections. The section boundaries can be based on a perfect object, and cross-sections can be determined by one of the optimization methods. This paper presents criteria, which ensure the reliable definition of the time of completion of the optimization process.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>критерий</kwd><kwd>оптимизация</kwd><kwd>особые свойства</kwd><kwd>устойчивость</kwd><kwd>частота</kwd><kwd>критическая сила</kwd><kwd>формы потери устойчивости</kwd><kwd>формы собственных колебаний</kwd><kwd>приведѐнные напряжения</kwd></kwd-group><kwd-group xml:lang="en"><kwd>criterion</kwd><kwd>optimization</kwd><kwd>specific properties</kwd><kwd>stability</kwd><kwd>frequency</kwd><kwd>critical force</kwd><kwd>buckling</kwd><kwd>eigen-frequency</kwd><kwd>reduced stresses</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">Boslovyak P.V., Emelyanova G.A. Optimization Mathematical Modeling of the Weight of Metal Structure of Suspended Belt Conveyor Linear Section // IFAC-PapersOnLine. 2018. V. 51. I. 30. 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