PSI - Issue 33

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

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

Procedia Structural Integrity 33 (2021) 586–597

© 2021 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 scientific committee of the IGF ExCo The results of the three-point bending tests were organized by quasi-CTOD, and it was found that the results were affected by the specimen size and notch depth. The modified Weibull stress model based on the local approach was able to evaluate the critical conditions of brittle fracture in a unified manner. Fracture probabilities at the initiation point of brittle fracture were defined and applied to each Weibull stress model, and the results were validated. The plastic strain distribution and microcrack appearance suggest the involvement of triaxiality in crack initiation. The inclusion of triaxiality in the fracture probability makes the initiation of brittle fracture more likely, and it suggests the possibility of including multiaxiality in the local approach. © 2021 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 Statement: Peer review under responsibility of the scientific committee of the IGF ExCo Keywords: Brittle fracture; CTOD; Local approach; Weibull stress; Finite element analysys Abstract In recent years, as the height and size of building layers have increased, the thicknesses of the components used have also increased, making brittle fracture more likely to occur. Fractur tests have often been p rformed on reduced scale steel. It is necessary to develop an approach f r brittle fracture evaluation that is less sensitive to the specimen size. In this study, we focused on the relationship between brittle fracture properties and geometrical shape and conducted a three-point bending test for isometric specimens wit a 4:2:1 geometry. The results of the three-point bending tests were organized by quasi-CTOD, and it was found that the results were affected by the specimen size and notch depth. The modified Weibull stress model based on the local approach was able to evaluate the critical conditions of brittle fracture in a unified manner. Fracture probabilities at the initiation point of brittle fracture were defined and applied to each Weibull stress model, and the results were validated. The plastic strain distribution and microcrack appearance suggest the involvement of triaxiality in crack initiation. The inclusion of triaxiality in the fracture probability makes the initiation of brittle fracture more likely, and it suggests the possibility of including multiaxiality in the local approach. © 2021 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 Statement: Peer review under responsibility of the scientific committee of the IGF ExCo Keywords: Brittle fracture; CTOD; Local approach; Weibull stress; Finite element analysys IGF26 - 26th International Conference on Fracture and Structural Integrity Specimen size effect on the brittle fracture properties of steel for buildings subjected to large earthquakes Naoya Oie * ,a , Tomoya Kawabata a , Shoichi Kishiki b , Tadao Nakagomi c a The University of Tokyo, 7-3-1 Hongo Bunkyo-ku, Tokyo 113-8654, Japan b Tokyo Institute of Technology, 2-12-1 Ookayama Meguro-ku, Tokyo 152-8550, Japan c Shinsyu University, 3-1-1 Asahi Matsumoto-city, Nagano 390-8621, Japan Abstract In recent years, as the height and size of building layers have increased, the thicknesses of the components used have also increased, making brittle fracture more likely to occur. Fracture tests have often been performed on reduced scale steel. It is necessary to develop an approach for brittle fracture evaluation that is less sensitive to the specimen size. In this study, we focused on the relationship between brittle fracture properties and geometrical shape and conducted a three-point bending test for isometric specimens with a 4:2:1 geometry. IGF26 - 26th International Conference on Fracture and Structural Integrity Specimen size effect on the brittle fracture properties of steel for buildings subjected to large earthquakes Naoya Oie * ,a , Tomoya Kawabata a , Shoichi Kishiki b , Tadao Nakagomi c a The University of Tokyo, 7-3-1 Hongo Bunkyo-ku, Tokyo 113-8654, Japan b Tokyo Institute of Technology, 2-12-1 Ookayama Meguro-ku, Tokyo 152-8550, Japan c Shinsyu University, 3-1-1 Asahi Matsumoto-city, Nagano 390-8621, Japan

* Corresponding author. Tel.: +81-3-5841-6517 E-mail address: oie-fracture@g.ecc.u-tokyo.ac.jp * Corresponding author. Tel.: +81-3-5841-6517 E-mail address: oie-fracture@g.ecc.u-tokyo.ac.jp

2452-3216 © 2021 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 Statement: Peer-review under responsibility of the scientific committee of the IGF ExCo 2452-3216 © 2021 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 Statement: Peer-review under responsibility of the scientific committee of the IGF ExCo

2452-3216 © 2021 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 scientific committee of the IGF ExCo 10.1016/j.prostr.2021.10.065