PSI - Issue 37

ScienceDirect ICSI 2021 The 4th International Conference on Structural Integrity Effects of long-term loading on Moabi wood beams in the tropical environment of Gabon: variability in properties and effects of exposure conditions on mechanical properties in 3-point bending tests Valérie Nsouami a , Nicaise Manfoumbi Boussougou b , Emilio Bastidas-Arteaga c , Rostand Moutou Pitti d,e a Ecole Normale Supérieure L’Enseignement Technique (ENSET), LaReVa Bois, Libreville, BP 3989, Gabon b Ecole Polytechnique de Masuku, Université des Sciences et Techniques de Masuku, Franceville, BP 901, Gabon c Laboratoire des Sciences de l’Ingénieur pour l’Environnement (LaSIE UMR CNRS 7356), La Rochelle Université, 17042 La R ochelle, France d Université Clermont Auvergne, Clermont Auvergne INP, CNRS, Institut Pascal, BP 10448, 63000 Clermont-Ferrand, France; e CENAREST, IRT, BP 14070 Libreville, Gabon ICSI 2021 The 4th International Conference on Structural Integrity Effects of long-term loading on Moabi wood beams in the tropical environment of Gabon: variability in properties and effects of exposure conditions on mechanical properties in 3-point bending tests Valérie Nsouami a , Nicaise Manfoumbi Boussougou b , Emilio Bastidas-Arteaga c , Rostand Moutou Pitti d,e a Ecole Normale Supérieure L’Enseignement Technique (ENSET), LaReVa Bois, Lib eville, BP 398 , Gabon b Ecole Polytechnique de Masuku, Université d s Sciences et Techniques de Masuku, Franceville, BP 901, Gabon c Laboratoire des Sciences de l’Ingénieur pour l’Environnement (LaSIE UMR CNRS 7356), La Rochelle Université, 17042 La R ochelle, France d Université Clermont Auvergne, Clermont Auvergne INP, CNRS, Institut Pascal, BP 10448, 63000 Clermont-Ferrand, France; e CENAREST, IRT, BP 14070 Libreville, Gabon ICSI 2021 The 4th International Conference on Structural Integrity Effects of long-term l ading on Moabi wood beams in the tropical environment of Gabon: variability in properties and effects of exposure conditions on mechanical properties in 3-point bending tests Valérie Nsoua i a , Nicaise Manfoumbi Boussougou b , Emilio Bastidas-Arteaga c , Rostand Moutou Pitti ,e a Ecole Normale Supérieure L’Enseignement Technique (ENSET), LaReVa Bois, Libreville, BP 3989, Gabon b Ecole Polytechnique de Masuku, Université des Sciences et Techniques de Masuku, Franceville, BP 901, Gabon c Laboratoire des Sciences de l’Ingénieur pour l’Environnement (LaSIE UMR CNRS 7356), La Rochelle Université, 17042 La R ochelle, France d Université Clermont Auvergne, Clermont Auvergne INP, CNRS, Institut Pascal, BP 10448, 63000 Clermont-Ferrand, France; e CENAREST, IRT, BP 14070 Libreville, Gabon www.elsevier.com/locate /procedia ICSI 2021 The 4th International Conference on Structural Integrity Effects of long-term loading on Moabi wood beams in the tropical environment of Gabon: variability in properties and effects of exposure conditions on mechanical properties in 3-point bending tests Valérie Nsouami a , Nicaise Manfoumbi Boussougou b , Emilio Bastidas-Arteaga c , Rostand Moutou Pitti d,e a Ecole Normale Supérieure L’Enseignement Technique (ENSET), LaReV Bois, Libreville, BP 3989, Gabon b Ecole Polytechnique de Masuku, Université des Sciences et Techniques de Masuku, Franceville, BP 901, Gabon c Laboratoire des Sciences de l’Ingénieur pour l’Environnement (LaSIE UMR CNRS 7356), La Rochelle Université, 17042 La R ochelle, France d Université Clermont Auvergne, Clermont Auvergne INP, CNRS, Institut Pascal, BP 10448, 63000 Clermont-Ferrand, France; e CENAREST, IRT, BP 14070 Libreville, Gabon Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000 www.elsevier.com/locate /procedia ICSI 2021 The 4th Intern tional Conference n Structural I tegrity Effects of long-term loading on Moabi wood beams in th tropical environme t of Gabon: variability in prop rt es and effects of exposure conditions on mechanical properties in 3-point bending tests Valérie Nsouami a , Nicaise Manfoumbi Boussougou b , Emilio Bastidas-Arteaga c , Rostand Moutou Pitti d,e a Ecol N rmale Supérieur L’Enseignement Technique (ENSET), LaReVa Bois, Libreville, BP 3989, Gabon b Ecole Polytechnique de Masuku, Université des Sciences et Techniques de Masuku, Franceville, BP 901, Gabon c Laboratoire des Sciences de l’Ingénieur pour l’Environnement (LaSIE UMR CNRS 7356), La Rochelle Université, 17042 La R ochelle, France d Université Clermont Auvergne, Clermont Auvergne INP, CNRS, Institut Pascal, BP 10448, 63000 Clermont-Ferrand, France; e CENAREST, IRT, BP 14070 Libreville, Gabon Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000 www.els vier.c m/locate / rocedia ICSI 2021 The 4th International C nference on Structural Integrity Effects of l g-term loading on Moabi wood beams in the tropical environment of Gabon: variability in roperties and effects of exposure conditions on mechanical properties in 3-point bending tests Valérie Nsouami a , Nicaise Manfoumbi Boussougou b , Emilio Bastidas-Arteaga c , Rostand Moutou Pitti d,e a Ecole Normale Supérieure L’Enseignement Technique (ENSET), LaReV Bois, Lib eville, BP 3989, Gabon b Ecole Polytechnique de Masuku, Université d s Sciences et Techniques de Masuku, Franceville, BP 901, Gabon c Laboratoire des Sciences de l’Ingénieur pour l’Environnement (L SIE UMR CNRS 7356), La Rochelle Université, 17042 La R ochelle, France d Université Clermont Auvergne, Clermont Auvergne INP, CNRS, Institut Pascal, BP 10448, 63000 Clermont-Ferrand, France; e CENAREST, IRT, BP 14070 Libreville, Gabon Available onlin at www.scien edirect.co ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000 w.elsevier.co /locate /procedia I SI 2021 he 4th International Conference on Structural Integrity ff ts f l -t r l ading on Moabi wo d beams in t tr l vir m t f G : ri lit i r ert s ff ts f exposure conditions on mechanical properties in 3-point bending tests Valérie Nsouami a , Nicaise anfou bi Boussougou b , Emilio Bastidas-Arteaga c , ostand outou Pitti d,e a Ecole Normale Supérieure L’Enseignement Technique (ENSET), LaReVa Bois, Libreville, BP 3989, Gabon b Ecole Polytechnique de Masuku, Université des Sciences et Techniques de Masuku, Franceville, BP 901, Gabon c Laboratoire des Sciences de l’Ingénieur pour l’Environnement (LaSIE UMR CNRS 7356), La Rochelle Université, 17042 La R ochelle, France d Université Clerm nt Auvergn , Clermon Auvergne INP, CNRS, Institut Pascal, BP 10448, 63000 Cl rmont-Ferrand, France; e CENAREST, IRT, BP 14070 Libreville, Gabon Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Pr cedia 00 (2019) 000 – 000 Procedia Structural Integrity 37 (2022) 576–581 2452-3216 © 2022 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 Pedro Miguel Guimaraes Pires Moreira 10.1016/j.prostr.2022.01.125 2452-3216  2022 The Authors. Published by ELSEVIER B.V This is an open access article under the CC BY-NC-ND licence (https://creativecommons.org/licences/by-nc-nd/4.0) Peer-review under responsibility of Pedro Miguel Guimaraes Pires Moreira 2452-3216  2022 The Authors. Published by ELSEVIER B.V This is an ope acces article under th CC BY-NC-ND lic nce (https://creativecommons.org/licences/by-nc-nd/4.0) Peer-review under responsibility of Pedro Miguel Guimaraes Pires Moreira 1. Introduction The forests of the Congo Basin are located in Central Africa and covers the following countries : Cameroon, the Central African Republic, Republic Democratic of the Congo, the Congo, Equatorial Guinea and Gabon (De Wasseige et al. 2012). They have a forestry potential of about 70% of Africa's forests. On the 530 million hectares of the Congo Basin, 300 million are covered by the forest. The forest area is made up of more than 99% primary or naturally regenerated forests, as opposed to plantations, and 46% of dense lowland forests (World Bank 2012). The Gabonese forest represents nearly 85% of its territory with nearly 400 species of wood. It is rich in Okoumé, Ozigo and other woods called : "various woods" which are in greater number, these are Azobé, Bilinga, Moabi, Movingui, Padouk, Sapelli etc. (Manfoumbi 2012). 2452-3216  2022 The Authors. Published by ELSEVIER B.V This is an open access article under the CC BY-NC-ND licence (https://creativecommons.org/licences/by-nc-nd/4.0) Peer-review under responsibility of Pedro Miguel Guimaraes Pires Moreira 1. Introduction The f r sts of the Congo Basin are located i Centr l Africa and covers the followi g countries : Cameroon, the Central Africa Republ c, Republic Dem cratic of the Cong , the Congo, Equatorial Guinea and Gabon (De Wasseige et al. 2012). Th y have a forestry p tential of about 70% of Africa's forests. On the 530 million hectares of the Congo Basin, 300 million are covered by th forest. The forest area is made up of more than 99% primary or naturally regenerated for sts, as oppo ed t plantations, and 46% of dense lowland forests (World Bank 2012). The Gabonese forest repres nts nearly 85% of its territory with nearly 400 species of wood. It is rich in Okoumé, Ozigo and other woods called : "various woods" which are in greater number, these are Azobé, Bilinga, Moabi, Movingui, Padouk, Sape li etc. (Manfoumbi 2012). Keywords: Moabi (Baillo ella toxisperma); variability; Long-term-loading; Bending  Corresponding author. Tel.: +33 6 79 58 24 25; fax: +33473407494. E-mail address: rostand.moutou_pitti@uca.fr 1. Introduction The forests of the Congo Basin are located i Centr l Africa and cover the follo i g countries : Cameroon, the Central Africa Repub ic, Republic Democratic of the Con o, the Congo, Equatorial Guinea and G bon (De Wasseige et al. 2012). They have a forestry p tential of about 70% of Africa's forests. On the 530 million hectares of the C ngo Basin, 300 million are c vered by the forest. The forest area is made up of more than 99% primary or naturally regenerated forests, as oppo ed to plantations, and 46% of dense lowland forests (World Bank 2012). The Gabonese forest repres nts ne rly 85% of its territory with nearly 400 species of wood. It is rich in Okoumé, Ozigo and other woods called : "various woods" w ich are in greater number, these are Azobé, Bilinga, Moabi, Movingui, Padouk, Sapelli etc. (Manfoumbi 2012). This work is devoted to 3-point bending tests performed on tropical specimens of Moabi ( Baillonella toxisperma ) from Gabon. The beams are formerly subjected to long-term loading in three media (air-conditioned, unsheltered and sheltered outdoor) in a tropical environment. The beams were sawn into nine 340 mm long sections and subdivided into three sections in the vertical direction (top section, middle section and bottom section). From each section, two specimens were extracted for the bending test, two for the tensile test and four for the compression test. In the present study, 81 bending specimens with a cross-section of 15 x 15 mm 2 and a length of 300 mm were used. The tests for the determination of the local modulus of elasticity and failure strength in bending were carried out according with NF EN 408. The results obtained show a strong influence of time and exposure environm nts on the m chanical parameters (bending s rength and modulus of elasticity). There is also a strong variability of these mechanical param ters along the length of the beams with a clear correlation between the sampling areas and the level of exposure; this confirms quite well the level of complexity of the wood material. © 2022 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- eview under responsibility of Pedro Miguel Guimaraes Pires Moreira Keywords: Moabi (Baillonella toxisperma); variability; Long-term-loading; Bending  Corr sp nding author. Tel.: +33 6 79 58 24 25; fax: +33473407494. E-mail address: rostand.moutou_pitti@uca.fr 1. Introduction The fores s of the Congo Basin are located in Central Africa and covers the following countries : C meroon the C ntral African Republic, Republic Democratic of the Congo, the Congo, Equatorial Guinea and Gabon (De Wasseige et al. 2012). They have a forestry potential f about 70% of Africa's forests. On the 530 million hectares of the C ngo Basin, 300 million are covered by the forest. The forest ar a s made up f more than 99% primary or naturally regenerated forests, as opposed to plantations, and 46% of dense lowland forests (World Bank 2012). The Gabonese forest represents nearly 85% of its territory with nearly 400 species of wood. It is rich in Okoumé, Ozigo and other woods called : "v rious woods" which are in greater number, these are Azobé, Bilinga, Moabi, Movingui, Padouk, Sapelli etc. (Manfoumbi 2012). is work is devoted to 3-point bending tes s performed on tropical specimens of Moabi ( Baillonella toxisperma ) from Gabon. The beams are for erly subj cted to long-term l ad g in three media (a r-conditione , unsheltered and sheltered outdoor) in a trop cal environment. The beams were sawn into nine 340 mm long sections and subdivid d into three se tions in the vertical direc ion (top section, middle section and bottom section). From each section, two specime s were extracted for the bend ng test, two for the tensile test and four for the compression test. In the pr sent s udy, 81 bending specimens with a cross-section of 15 x 15 mm 2 and a l ngth of 300 mm were used. The tests for the determinati n of the local modulus of e asti ity and failure strength in bending were carried out ac ording wi h NF EN 408. The results obtained show a strong influe ce of time a d exposure environments on the mechanical parameters (bending trength and modulus of elasticity). There i also a strong variability of these mechanical parameters along the length of the beams with a clear corr lation between the sampling areas and the level of exposure; this confirms qu te well the level of complexity of the wood material. © 2022 The Authors. Published by ELSEVIER B.V. This is an ope access article under the CC BY-NC-ND lic nse (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of Pedro Miguel Guimaraes Pires Moreira Keywords: Moabi (Baillo ella toxisperma); variability; Long-term-loading; Bending  Correspon ing author. Tel.: +33 6 79 58 24 25; fax: +33473407494. E-mail ddress: rostand.moutou_pitti@uca.fr 1. Introduction The forests f the Congo Basin are located in Centr l Africa and covers the followi g countries : Cameroon, the Central Africa Re ublic, Republic Democratic of the Cong , the Congo, Equatorial Guinea and Gabon (De Wasseige et al. 2012). They have a forestry potential of about 70% of Africa's forests. On the 530 million hectares f the Congo Basin, 300 million a e c vered by th fore t. The forest ar a is made up f more than 99% primary or naturally reg nerated for sts, as oppo ed t plantations, and 46% of dense lowland forests (World Bank 2012). The Gabonese forest repres nts ne rly 85% f its territory w th n rly 400 species of wood. It is rich in Okoumé, Ozigo and other woods called : "various woods" which are in greater number, these are Azobé, Bilinga, Moabi, Movingui, Padouk, Sapelli etc. (Manfoumbi 2012). This work is devoted to 3-point bending tests performed on tropical specimens of oabi ( Bail onella oxisp rma ) from G bo . Th beams are formerly subjected to long-term loading in three medi (air-conditioned, unsheltered and sheltered outdoor) in a tropical environment. The beams were sawn into nine 340 mm long sections and sub ivid d into three sections in the vertical direction (t p section, middle section and bottom section). From each section, two specim ns were extracted for the bending test, two for the tensile test and four for the compression test. In the present study, 81 bending specimens with a cross-section of 15 x 15 mm 2 and a length of 300 mm were used. The tests for the determination of the local modulu of elasticity and failure str ngth n bending were carr ed out acc rd ng with NF EN 408. The results obtained show a strong influence of time and exposure environments on t mechanical parameters (bending strength and modulus of elasticity). There is also a strong variability of ese mechanical parameters long the length of the beams wi h a clear correlation between the sampling areas and the level of exposure; this confirms quite wel th level of complexity of the w od material. © 2022 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 Pedro Miguel Guimaraes Pires oreira Keywords: Moabi (Baillo ella toxisperma); variability; Long-term-loading; Bending  Corresponding author. Tel.: +33 6 79 58 24 25; fax: +33473407494. E-mail address: rostand.moutou_pitti uca.fr 1. Introduction The forests of the Congo Basin are located in Central Africa and covers the follo ing countries : C meroon, the C ntral African Republic, Republic e ocratic of the Congo, the Congo, Equatorial uinea and abon ( e Wasseige et l. 2012). They have a forestry potential of about 70% of Africa's forests. n the 530 illion hectares of the Congo Basin, 300 million are covered by the forest. The forest area is made up of more than 99% primary or naturally regenerated forests, as opposed to plantations, and 46% of dense lowland forests (World Bank 2012). The Gabones forest represents nearly 85 of it territory with nearly 400 species of ood. It is rich in kou é, Ozigo and other woods called : "various woods" which are in greater number, these are Azobé, Bilinga, Moabi, Movingui, Padouk, Sapelli etc. ( anfou bi 2012). © 2022 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 Pedro Miguel Guimaraes Pires Moreira © 2022 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 Pedro Miguel Guimaraes Pires Moreira Keywords: Moabi (Baillonella toxisperma); variability; Long-term-loading; Bending  Corresponding author. Tel.: +33 6 79 58 24 25; fax: +33473407494. E-mail address: rostand.moutou_pitti@uca.fr 1. Introduction The forests of the Congo Basin are located in Central Africa and covers the following countries : Cameroon, the Central African Republic, Republic Democratic of the Congo, the Congo, Equatorial Guinea and Gabon (De Wasseige et al. 2012). They have a forestry potential of about 70% of Africa's forests. On the 530 million hectares of the Congo Basin, 300 million are covered by the forest. The forest area is made up of more than 99% primary or naturally regenerated forests, as opposed to plantations, and 46% of dense lowland forests (World Bank 2012). The Gabonese forest represents nearly 85% of its territory with nearly 400 species of wood. It is rich in Okoumé, Ozigo and other woods called : "various woods" which are in greater number, these are Azobé, Bilinga, Moabi, Movingui, Padouk, Sapelli etc. (Manfoumbi 2012). is work is dev ted to 3-point bending tests performed on tropical specimens of Moabi ( Baillonella toxisperma ) fr m Gabon. The beams are for erly subjected to long-term l adi g in three media (air-conditione , unsheltered and sheltered outdoor) in a tropical environme t. The beams were sawn into nine 340 mm long sections and subdivid d into three se tions in the vertical direction (top section, middle section and bottom section). From each section, two specime s were extracted for the bending test, two for the tensile test and four for the compression test. In the pr sent study, 81 bending specimens with a cross-section of 15 x 15 mm 2 and a length of 300 mm were used. The tests for the determination of the local modulus of elasticity and failure strength in bending were carried out according with NF EN 408. The results obtained show a strong influence of time a d exposure environments on the mechanical parameters (bending str ngth and modulus of elasticity). There is also a strong variability of these mechanical parameters along the length of the beams with a clear correlation between the sampling areas and the level of exposure; this confirms quite well the level of complexity of the wood material. © 2022 The Authors. Published by ELSEVIER B.V. This is an ope access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of Pedro Miguel Guimaraes Pires Moreira Keywords: Moabi (Baillonella toxisperma); variability; Long-term-loading; Bending  Corresponding author. Tel.: +33 6 79 58 24 25; fax: +33473407494. E-mail address: rostand.moutou_pitti@uca.fr This w rk is devo ed to 3-point bending tests performed on tropical specimens of Moabi ( Baillon lla toxisperma ) from Gabon. The beams are formerly subjected to l ng-term loading in three media (air-conditioned, unshelter d and sheltered utdoor) i a tropical environment. The beams were sawn into nin 340 mm long sectio s and subdivided into three sections in the vertical di ection (top section, middle section and bottom section). From eac section, two specimens were extracted for the bendi g test, two for the tensile test and four for the compression test. In the present study, 81 bending specimens with a cross-section of 15 x 15 mm 2 and a length of 300 m were used. The tests for the determination of the local modulus of elasticity and failure strength in bending we carried out according with NF EN 408. The results obtained show a strong influence of time and exposure environments on the mechanical parameters (bending strength and modulus of elasticity). There is also a strong variability of these mechanical parameters along the length of the beams with a clear correlation between the sampling areas and the level of exposure; this confirms quite well the level of complexity of the wood material. © 2022 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 Pedro Miguel Guimaraes Pires Mor ira Keywords: Moabi (Baillo ella toxisperma); variability; Long-term-loading; Bending  Corresponding author. Tel.: +33 6 79 58 24 25; fax: +33473407494. E-mail address: rostand.moutou_pitti@uca.fr Abstract This work is devoted to 3-point bending tests performed on tropical specimens of Moabi ( Baillonella toxisperma ) from Gabon. The beams are formerly subjected to long-term loading in three media (air-conditioned, unsheltered and sheltered outdoor) in a tropical environment. The beams were sawn into nine 340 mm long sections and subdivided into three sections in the vertical direction (top section, middle section and bottom section). From each section, two specimens were extracted for the bending test, two for the tensile test and four for the compression test. In the present study, 81 bending specimens with a cross-section of 15 x 15 mm 2 and a length of 300 mm were used. The tests for the determination of the local modulus of elasticity and failure strength in bending were carried out according with NF EN 408. The results obtained show a strong influence of time and exposure environments on the mechanical parameters (bending strength and modulus of elasticity). There is also a strong variability of these mechanical parameters along the length of the beams with a clear correlation between the sampling areas and the level of exposure; this confirms quite well the level of complexity of the wood material. © 2022 The Authors. Published by ELSEVIER B.V. This is an ope acce s article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of Pedro Miguel Guimaraes Pires Moreira Abstract Abstract Abstract Structural Integrity Procedia 00 (2019) 000 – 000 Structural Integrity Procedia 00 (2019) 000 – 000 ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000 www.elsevier.com/locate /procedia www.elsevier.com/locate /procedia www.elsevier.com/locate /procedia Abstract Abstract This work is devoted to 3-point bending tests performed on tropical specimens of Moabi ( Baillonella toxisperma ) from Gabon. The beams are formerly subjected to long-term loading in three media (air-conditioned, unsheltered and sheltered outdoor) in a tropical environment. The beams were sawn into nine 340 mm long sections and subdivided into three sections in the vertical direction (top section, middle section and bottom section). From each section, two specimens were extracted for the bending test, two for the tensile test and four for the compression test. In the present study, 81 bending specimens with a cross-section of 15 x 15 mm 2 and a length of 300 mm were used. The tests for the determination of the local modulus of elasticity and failure strength in bending were carried out according with NF EN 408. The results obtained show a strong influence of time and exposure environments on the mechanical parameters (bending strength and modulus of elasticity). There is also a strong variability of these mechanical parameters along the length of the beams with a clear correlation between the sampling areas and the level of exposure; this confirms quite well the level of complexity of the wood material. Abstract

2452-3216  2022 The Authors. Published by ELSEVIER B.V