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<article 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" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" article-type="research-article" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Structural Mechanics of Engineering Constructions and Buildings</journal-id><journal-title-group><journal-title xml:lang="en">Structural Mechanics of Engineering Constructions and Buildings</journal-title><trans-title-group xml:lang="ru"><trans-title>Строительная механика инженерных конструкций и сооружений</trans-title></trans-title-group></journal-title-group><issn publication-format="print">1815-5235</issn><issn publication-format="electronic">2587-8700</issn><publisher><publisher-name xml:lang="en">Peoples’ Friendship University of Russia named after Patrice Lumumba (RUDN University)</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">23962</article-id><article-id pub-id-type="doi">10.22363/1815-5235-2020-16-3-226-232</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>Experimental researches</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>Экспериментальные исследования</subject></subj-group><subj-group subj-group-type="article-type"><subject>Research Article</subject></subj-group></article-categories><title-group><article-title xml:lang="en">Experimental determination of the limiting flexibility of eucalyptus wood for axially compressed elements</article-title><trans-title-group xml:lang="ru"><trans-title>Экспериментальное определение предельной гибкости древесины эвкалипта для центрально сжатых элементов</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Cajamarca-Zuniga</surname><given-names>David</given-names></name><name xml:lang="ru"><surname>Кахамарка-Сунига</surname><given-names>Давид</given-names></name></name-alternatives><bio xml:lang="en"><p>Master of Science, PhD postgraduate student, Department of Civil Engineering, Engineering Academy of RUDN University; Docent of the Department of Civil Engineering at CUC</p></bio><bio xml:lang="ru"><p>аспирант РУДН; доцент инженерного факультета КУК</p></bio><email>cajamarca.zuniga@gmail.com</email><xref ref-type="aff" rid="aff1"/><xref ref-type="aff" rid="aff2"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Carrasco</surname><given-names>Cristhian</given-names></name><name xml:lang="ru"><surname>Карраско</surname><given-names>Кристиан</given-names></name></name-alternatives><bio xml:lang="en"><p>Civil Engineer graduate, Department of Civil Engineering</p></bio><bio xml:lang="ru"><p>инженер-строитель, выпускник инженерного факультета</p></bio><email>cajamarca.zuniga@gmail.com</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Molina</surname><given-names>Belen</given-names></name><name xml:lang="ru"><surname>Молина</surname><given-names>Белен</given-names></name></name-alternatives><bio xml:lang="en"><p>Civil Engineer graduate, Department of Civil Engineering</p></bio><bio xml:lang="ru"><p>инженер-строитель, выпускница инженерного факультета</p></bio><email>cajamarca.zuniga@gmail.com</email><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">Catholic University of Cuenca</institution></aff><aff><institution xml:lang="ru">Католический университет г. Куэнка</institution></aff></aff-alternatives><aff-alternatives id="aff2"><aff><institution xml:lang="en">Peoples’ Friendship University of Russia (RUDN University)</institution></aff><aff><institution xml:lang="ru">Российский университет дружбы народов</institution></aff></aff-alternatives><pub-date date-type="pub" iso-8601-date="2020-12-15" publication-format="electronic"><day>15</day><month>12</month><year>2020</year></pub-date><volume>16</volume><issue>3</issue><issue-title xml:lang="en">VOL 16, NO3 (2020)</issue-title><issue-title xml:lang="ru">ТОМ 16, №3 (2020)</issue-title><fpage>226</fpage><lpage>232</lpage><history><date date-type="received" iso-8601-date="2020-06-12"><day>12</day><month>06</month><year>2020</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2020, Cajamarca-Zuniga D., Carrasco C., Molina B.</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2020, Кахамарка-Сунига Д., Карраско К., Молина Б.</copyright-statement><copyright-year>2020</copyright-year><copyright-holder xml:lang="en">Cajamarca-Zuniga D., Carrasco C., Molina B.</copyright-holder><copyright-holder xml:lang="ru">Кахамарка-Сунига Д., Карраско К., Молина Б.</copyright-holder><ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/"/><license><ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">http://creativecommons.org/licenses/by/4.0</ali:license_ref></license></permissions><self-uri xlink:href="https://journals.rudn.ru/structural-mechanics/article/view/23962">https://journals.rudn.ru/structural-mechanics/article/view/23962</self-uri><abstract xml:lang="en"><p>Relevance. Wood is one of the most widely used building materials throughout history, and because of its physical-mechanical properties it mainly has been used in flexed and compressed elements. Eucalyptus was introduced to Latin America in the mid-19th century and nowadays is one of the most used woods for construction in the Andean region of Ecuador. To designing slender structural elements under axial loading engineers usually use the Euler formula, but it is applicable only if the compression stress does not exceed the proportional limit. One way to determine if the compression stress will be below the proportional limit is by comparing of the slenderness of the element with the limiting flexibility of its material which allows knowing if the buckling will occur in the elastic zone where Euler formula applies. The aim of the work - determine the magnitude of the limiting flexibility of eucalyptus, since this wood has been the subject of some investigations, however, no information about the limiting flexibility magnitude for the calculation of axially compressed elements. Methods. The laboratory tests to determine the magnitudes of the modulus of elasticity, proportional limit, admissible compression stress and limiting flexibility was carried out. Results. This experimental investigation shows that the magnitude of the limiting flexibility or so-called critical slenderness ratio for eucalyptus globulus is 59.</p></abstract><trans-abstract xml:lang="ru"><p>Актуальность. Древесина является одним из наиболее широко используемых строительных материалов на протяжении всей истории и, благодаря своим физико-механическим свойствам, в основном применяется в изгибаемых и сжатых элементах. Эвкалипт был завезен в Латинскую Америку в середине XIX в. и в настоящее время является наиболее востребованной древесиной для строительства в Андском регионе Эквадора. Для расчета стержней при осевом сжатии обычно используется формула Эйлера, но она применима, лишь если напряжение сжатия не превышает величины предела пропорциональности. Один из способов определить, находится ли напряжение ниже предела пропорциональности, заключается в сравнении гибкости элемента с предельной гибкостью его материала, что позволяет узнать, будет ли расчет на устойчивость проводится в упругой зоне, где применима формула Эйлера. Цель исследования - определить величину предельной гибкости эвкалипта, так как, хотя эта древесина была предметом нескольких исследований, по-прежнему нет сведений о величине ее предельной гибкости для расчета центрально-сжатых элементов на устойчивость. Методы. Проводились лабораторные испытания для установления величины модуля упругости, предела пропорциональности, допустимого напряжения сжатия и предельной гибкости. Результаты. Экспериментальное исследование показывает, что величина предельной гибкости для эвкалипта шаровидного равна 59.</p></trans-abstract><kwd-group xml:lang="en"><kwd>axial loading</kwd><kwd>central-compressed elements</kwd><kwd>critical force</kwd><kwd>critical slenderness ratio</kwd><kwd>eucalyptus</kwd><kwd>limiting flexibility</kwd><kwd>proportionality stress</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>осевое сжатие</kwd><kwd>критическая сила</kwd><kwd>эвкалипт</kwd><kwd>предельная гибкость</kwd><kwd>гибкость элемента</kwd><kwd>предел пропорциональности</kwd></kwd-group><funding-group/></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>Warren E., Smith R.G.B., Apiolaza L.A., Walker J.C.F. Effect of stocking on juvenile wood stiffness for three Eucalyptus species. 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