{"id":1401,"date":"2023-07-18T06:30:47","date_gmt":"2023-07-18T06:30:47","guid":{"rendered":"http:\/\/bambutec.com.br\/?p=1401"},"modified":"2023-07-21T21:20:39","modified_gmt":"2023-07-21T21:20:39","slug":"analysis-of-the-bending-behavior-of-bamboo-culms-with-a-full-longitudinal-crack","status":"publish","type":"publicacao","link":"https:\/\/bambutec.com.br\/en\/publicacao\/analysis-of-the-bending-behavior-of-bamboo-culms-with-a-full-longitudinal-crack\/","title":{"rendered":"Analysis of the bending behavior of bamboo culms with a full longitudinal crack"},"content":{"rendered":"<p class=\"wp-block-paragraph\">Engineering Structures Volume 251, Part A, 15 January 2022, 113501. <a href=\"https:\/\/www.sciencedirect.com\/science\/article\/pii\/S0141029621016035#!\" target=\"_blank\" rel=\"noopener noreferrer\">Access<\/a>&nbsp;&gt;&gt;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">L.E. Moreira; M. Seixas<\/p>\n\n\n\n<p class=\"wp-block-paragraph\" id=\"sp0010\"><strong>Abstract: The creep behavior of bamboo culms under long-term loadings was investigated in the present work.\u00a0Phyllostachys aurea\u00a0bamboo samples were subjected to four-point flexural creep tests at loads corresponding to 30%, 50%, and 80% of the bamboo's short-term bending strength. Creep and recovery behavior were evaluated for each loading level at room temperature over 398\u00a0days, allowing the attainment of primary, secondary, and tertiary creep stages. The failure of one creep test sample occurred at 73\u00a0MPa, and the failure mode due to creep was described. Creep mechanisms assessed included node flexibility, cylindrical bending, and shear. Node flexibility contributed 50\u201374% of total deflection, cylindrical bending contributed 24\u201348%, while shear contributed less than 2%. A four-element Burgers mechanical model was proposed, matching the experimental results for all loading levels. A viscous coefficient parameter of 4.3 to 30\u00d7\u2009103\u00a0GPa.day was inferred, corresponding to the linear dashpot\u00a0n1. These models estimated the bamboo culm deflection over time and predicted failure at a 40% increase in deflection. Overall, this study provided comprehensive insights into the long-term structural behavior of bamboo culms for use in design and engineering applications.<\/strong> This paper investigates the\u00a0bending stiffness\u00a0of bamboo culms with and without the presence of a full\u00a0longitudinal crack\u00a0of the culm wall. The study aims to quantify experimentally the loss of resistance of cracked bamboo tubes in bending, in compliance with numerical modeling using the finite element method (FEM) and the classic equations of Vlasov. Experimental tests were conducted with six specimens of\u00a0<em>Phyllostachys edulis<\/em>\u00a0bamboo (Moso), subjected to three-point bending tests. Firstly, the samples were mechanically tested in its full-culm state without the presence of cracks and, then, with a longitudinal crack along the total lenght of the culm. The cracks were positioned in the worst-case situation, i.e., perpendicular to the bending plane. The compliance between experimental and numerical displacements measured at the center span of the samples and in FE models showed with accuracy the loss of the bending stiffness of cracked bamboo culms. The study showed that isotropic numerical models can attain the flexural properties of bamboo tubes in perfect conditions, without the presence of cracks. Although, to assess the flexural properties of bamboo tubes with the presence of a full longitudinal crack it was necessary to model the bamboo tube considering orthotropy. The numerical analysis and the Vlasov equations described with good precision the stress field in the analyzed tubes. Each sample presented a different loss of resistance, depending if the crack cut or not the diaphragms beyond the culm wall, showing a maximum loss of stiffness of 63% for cracked specimens. Thus, the results presented a significant loss of bending stiffness of cracked bamboo culms, if the culm wall cracks from one end to another, which can be considered as a damaged tube.<\/p>","protected":false},"excerpt":{"rendered":"<p>Engineering Structures Volume 251, Part A, 15 January 2022, 113501. Clique para acessar&nbsp;&gt;&gt; L.E. Moreira; M. Seixas Resumo: This paper investigates the\u00a0bending stiffness\u00a0of bamboo culms with and without the presence of a full\u00a0longitudinal crack\u00a0of the culm wall. The study aims to quantify experimentally the loss of resistance of cracked bamboo tubes in bending, in compliance [&hellip;]<\/p>","protected":false},"featured_media":1408,"template":"","format":"standard","categories":[52],"tags":[53,58,56,54,55,57],"class_list":["post-1401","publicacao","type-publicacao","status-publish","format-standard","has-post-thumbnail","hentry","category-publicacoes","tag-bamboo-full-culms","tag-bending-stiffness","tag-experimental-analysis","tag-longitudinal-crack","tag-numerical-modeling","tag-three-point-bending-tests"],"blocksy_meta":[],"_links":{"self":[{"href":"https:\/\/bambutec.com.br\/en\/wp-json\/wp\/v2\/publicacao\/1401","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/bambutec.com.br\/en\/wp-json\/wp\/v2\/publicacao"}],"about":[{"href":"https:\/\/bambutec.com.br\/en\/wp-json\/wp\/v2\/types\/publicacao"}],"version-history":[{"count":6,"href":"https:\/\/bambutec.com.br\/en\/wp-json\/wp\/v2\/publicacao\/1401\/revisions"}],"predecessor-version":[{"id":1877,"href":"https:\/\/bambutec.com.br\/en\/wp-json\/wp\/v2\/publicacao\/1401\/revisions\/1877"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/bambutec.com.br\/en\/wp-json\/wp\/v2\/media\/1408"}],"wp:attachment":[{"href":"https:\/\/bambutec.com.br\/en\/wp-json\/wp\/v2\/media?parent=1401"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/bambutec.com.br\/en\/wp-json\/wp\/v2\/categories?post=1401"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/bambutec.com.br\/en\/wp-json\/wp\/v2\/tags?post=1401"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}