A study on hole arrangement and bearing capacity of glued laminated timber beams with multiple round holes

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K04796
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 23010:Building structures and materials-related
• Research Institution: Osaka Metropolitan University (2022); Osaka City University (2020-2021)
• Principal Investigator: Okamoto Shigefumi 大阪公立大学, 大学院生活科学研究科, 講師 (20769806)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 円形孔 / 集成材 / 割裂

Outline of Final Research Achievements

The purpose of this study is to establish a design method for the splitting strength of glued laminated timber beam with multiple round holes. First, a design method for splitting strength is proposed by formulating the ratio of the maximum tensile stress perpendicular to the grain acting around the hole as the distance between the holes decreases, using finite element analysis. Then, a three-point bending tests were conducted on a glued laminated wood beam with two round holes, and the experimental and calculated values were compared to confirm the validity of the proposed design method. In addition, we proposed a distance between the holes that would not reduce the bearing capacity.

Free Research Field

木質構造

Academic Significance and Societal Importance of the Research Achievements

日本の有孔梁の指針類は、「枠組壁工法建築物設計の手引」か「JIS A 3301」に示されている仕様規定制限のみで、有孔梁の耐力算定方法が確立されていないのが現状である。住宅などの建築現場では安全性の検討を行わずに切り欠きや孔が設けられ場合があり、適切な評価法が望まれてきた。本研究では、円径孔が一つの場合と二つの場合の耐力算定方法を提案し、この成果を応用することにより有孔梁の簡易な設計法や配置基準を検討することができ、安全な建築物の普及が期待される。