PSI - Issue 68

ScienceDirect Available online at www.sciencedirect.com ScienceDirect Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2025) 000–000 Available online at www.sciencedirect.com Procedia Structural Integrity 68 (2025) 119–125 Structural Integrity Procedia 00 (2025) 000–000

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European Conference on Fracture 2024 Fatigue strength of laminated bamboo lumber Pascal Franck a, *, Oliver Bletz-Mühldorfer a , Leander Bathon a , Ronja Scholz b , Frank Walther b a RheinMain University of Applied Sciences, Laboratory of Timber Engineering, Kurt-Schumacher-Ring 18, 65197 Wiesbaden, Germany b TU Dortmund University, Chair of Materials Test Engineering (WPT), Baroper Str. 303, 44227 Dortmund, Germany Abstract Today, the global demand for renewable and sustainable materials is higher than ever. A promising material in this regard is the fast-growing natural resource bamboo. Research activities in the field of bamboo have increased in recent years due to its availability in many regions of the world and its positive influence on the ecosystem (e.g., high potential for carbon restoration). The mechanical properties of bamboo are comparable or even superior to those of commonly used wood species. Processing the raw bamboo culms into engineered bamboo products can enhance these properties, as it eliminates many naturally grown flaws and misalignments of the culm. In this study, the properties of laminated bamboo lumber (LBL) made from Phyllostachys pubescens (“Moso” bamboo) under fatigue loading in tensile direction were explored. Understanding the fatigue behavior of materials used in various technical fields is essential because all components are exposed to cyclic loads. Additionally, the load levels leading to material failure are significantly lower than the characteristic values measured under (quasi)-static loading. The initial cyclic tests of the LBL specimens yielded very promising results for potential applications in technical fields, such as civil engineering. The digital image correlation (DIC) systems were used to gain an initial understanding of the damage mechanisms that led to the failure of the specimens. It could be proven, that the nodal areas of the bamboo tend to be high-loaded and are preferred initiation points of fracture. Keywords: Sustainability; bamboo; mechanical properties; fatigue testing; digital image correlation (DIC) 1. Introduction Climate change is the greatest challenge of the last decades and the threat is constantly increasing since the effects of global warming and environmental catastrophes are already clearly noticeable around the world. Thus, there is an European Conference on Fracture 2024 Fatigue strength of laminated bamboo lumber Pascal Franck a, *, Oliver Bletz-Mühldorfer a , Leander Bathon a , Ronja Scholz b , Frank Walther b a RheinMain University of Applied Sciences, Laboratory of Timber Engineering, Kurt-Schumacher-Ring 18, 65197 Wiesbaden, Germany b TU Dortmund University, Chair of Materials Test Engineering (WPT), Baroper Str. 303, 44227 Dortmund, Germany Abstract Today, the global demand for renewable and sustainable materials is higher than ever. A promising material in this regard is the fast-growing natural resource bamboo. Research activities in the field of bamboo have increased in recent years due to its availability in many regions of the world and its positive influence on the ecosystem (e.g., high potential for carbon restoration). The mechanical properties of bamboo are comparable or even superior to those of commonly used wood species. Processing the raw bamboo culms into engineered bamboo products can enhance these properties, as it eliminates many naturally grown flaws and misalignments of the culm. In this study, the properties of laminated bamboo lumber (LBL) made from Phyllostachys pubescens (“Moso” bamboo) under fatigue loading in tensile direction were explored. Understanding the fatigue behavior of materials used in various technical fields is essential because all components are exposed to cyclic loads. Additionally, the load levels leading to material failure are significantly lower than the characteristic values measured under (quasi)-static loading. The initial cyclic tests of the LBL specimens yielded very promising results for potential applications in technical fields, such as civil engineering. The digital image correlation (DIC) systems were used to gain an initial understanding of the damage mechanisms that led to the failure of the specimens. It could be proven, that the nodal areas of the bamboo tend to be high-loaded and are preferred initiation points of fracture. Keywords: Sustainability; bamboo; mechanical properties; fatigue testing; digital image correlation (DIC) 1. Introduction Climate change is the greatest challenge of the last decades and the threat is constantly increasing since the effects of global warming and environmental catastrophes are already clearly noticeable around the world. Thus, there is an © 2025 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 ECF24 organizers

* Corresponding author. Tel.: +49 611 9495 -1523; fax: +49 611 9495 -1532. E-mail address: pascal.franck@hs-rm.de

2452-3216 © 2025 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 ECF24 organizers 10.1016/j.prostr.2025.06.031 2452-3216 © 2025 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 ECF24 organizers 2452-3216 © 2025 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 ECF24 organizers * Corresponding author. Tel.: +49 611 9495 -1523; fax: +49 611 9495 -1532. E-mail address: pascal.franck@hs-rm.de