PSI - Issue 28

Available online at www.sciencedirect.com Available online at w.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000–000

www.elsevier.com/locate/procedia

ScienceDirect ScienceDirect

Procedia Structural Integrity 28 (2020) 491–501 Structural Integrity Procedia 00 (2019) 000–000

www.elsevier.com/locate/procedia

2452-3216 © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo 10.1016/j.prostr.2020.10.058 2452-3216 © 2020 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo 2452-3216 © 2020 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the European Structural Integrity Society (ESIS) ExCo Abstract Wood is a material used since the beginning of history by Man, It has proved very practical in various fields, and we quote mainly the sector of building and furniture. Known to be anisotropic, cellular and very complex. Its structural properties have a major influence on the mechanical behavior of the material. The interest of this present work is to further enrich our knowledge of this material through the study of its behavior in the face of external stresses that generate the mode II fracture. To do this, the choice of a specimen to study is imperative, knowing that there is no standardized test for the study of this phenomenon; we then began by studying the different prototypes of specimens mentioned in the literature and identified their advantages and disadvantages. We concluded that each test presents many difficulties of use and a great dispersion of the results caused on the one hand, by the nature of the material but mainly by the instability of the propagation of the crack. Based on this state of the art and the various experimental devices available to us, we have developed a test specimen prototype based on a tensile test for the study of the mode II of fracture. To carry out this work, in order to apprehend the studied material, we began by carrying out a complete characterization of the studied essence: Eucalyptus Grandis that includes the two aspects: mechanical and physical. . The dispersive nature of the material, the tests of the feasibility of the prototype developed and the number of notches require the reproduction of the test, hence the large amount of testing. During this test, the wood has adopted a fragile character, which gives it a linear behavior until it reaches a break with a stable propagation of the crack. This has been noticed for all notch lengths. The microscopic analysis that we carried out enabled us to validate the mode of fracture, to do this we studied the fracture facies of each length of notch using the scanning electron microscope. To determine the G II energy mode II initiation fracture toughness, we used the global approach using the convenience method and the theory of IRWIN KIES, we then deduced the K II constraint factor. We wanted to compare the results obtained with those of the literature but this operation can hardly be feasible except for the case, if we compare that order of magnitude because the tests are not done under the same conditions and using even the species. This led us to reproduce the most used test in the research and which is more accurate compared to other experiments in this case the test 4ENF. Keywords: mechanical behavior, mode II fracture, the propagation of the crack, characterization, and Eucalyptus Grandis Abstract Wood is a material used since the beginning of history by Man, It has proved very practical in various fields, and we quote mainly the sector of building and furniture. Known to be anisotropic, cellular and very complex. Its structural properties have a major influen e on the mechanical behavior of the material. The interest of this present work is to further enrich our knowledge of this material through the study of its behavior in the face of external stresses that generate the mode II fracture. To do this, the choice of a specimen o study is imp rative, k owing t at there is no stand rdized test for the study of this phenome on; we then began by studying the different prototypes of specimens mentioned in the iter ture and identified thei advantages and dis dvantages. We co luded that ach test pr sents many difficulties of use and a great disp rsion of the res l s caused on the one hand, by t e nature of the material but mainly by the instability of th prop gation of the crack. Based on this st te of the art and the vari us experimental devices availabl to us, we have develop d a test specimen prototype bas d on a tensile test f r the study of the mode II of fracture. To carry out this w rk, in order to appr he d the studied material, we began by c rrying out compl te characterization of the studied es ce: Eucalyptus Grandis that includes the two aspects: mechanical nd physical. . The dispersiv t aterial, the tests of the feasibility of the prototy e developed and the number f notches requir the reproduction of the t st, hence the large amount f testing. During this t st, the wood has adopted a fragile character, which gives it a linear b havior until it each s a break with a s able propagati n of the crack. This has been noticed for all notch le gths. The micr scopic analysis that we carried out enabled us to validate the mode of fracture, to do this we studi d the fracture f cies of each length of notch using the scanning e ectron microscop . To determine the G II n rgy mo e II initiation fracture toughness, we used the global approac using the convenience m thod and the theory of IRWIN KIES, we then deduced the K II constraint factor. We wanted to compare the results obtained with those of the litera ure but this oper tion ca hardly be feasible except for the case, if we compare order of magni ude eca se the tests are not d n under the same c nd tions and using ven the spe i . This led us to reprodu e the most u ed test in the esearch and which is mo e accurate compared to other experiments in this case the test 4ENF. Keywords: mechanical behavior, mode II fracture, the propagation of the crack, characterization, and Eucalyptus Gr ndis 1st Virtual European Conference on Fracture Experimental approach for the study of wood strength at fracture in mode II by using a modified prototype test specimen and confrontation of the results with those of the 4ENF test. Application: Eucalyptus Grandis A. Saoud 1 , A. Elamri 1 , and K. Kimakh 1 1 Laboratoire de contrôle et caractérisation mécanique des matériaux et des structures LCCMMS, ENSEM, Université Hassan II, Casablanca 1st Virtual European Conference on Fracture Experimental approach for the study of wood strength at fracture in mode II by using a modified prototype test specimen and confrontation of the results with those of the 4ENF test. Application: Eucalyptus Grandis A. Saoud 1 , A. Elamri 1 , and K. Kimakh 1 1 Laboratoire de contrôle et caractérisation mécanique des matéria x et des struct re LCCMMS, ENSEM, Université Hassan II, Casablanca