2022 Fiscal Year Final Research Report
Optimization of connection detail of welded beam end based on the prediction approach of brittle fracture
Project/Area Number |
19K04699
|
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 | Sojo University |
Principal Investigator |
AZUMA Koji 崇城大学, 工学部, 教授 (80320414)
|
Co-Investigator(Kenkyū-buntansha) |
岩下 勉 有明工業高等専門学校, 創造工学科, 教授 (10332090)
|
Project Period (FY) |
2019-04-01 – 2023-03-31
|
Keywords | 鋼構造 / 溶接接合部 / 脆性破壊 / 接合部詳細 / スカラップ / 破壊評価 / 塑性拘束 |
Outline of Final Research Achievements |
This study concerns the applicability of modified weld access holes and the partial cutting fillet welds (PCFW) procedure in assembled I-section beam. It was investigated that the suitable shape of weld access hole which could be used in the field-welded connection, using by experiment and FE analysis. The cyclic loading tests using beam-to-diaphragm joint models, which were designated to represent beam-to-column connections with through diaphragm, were conducted. The ductile cracks initiated at the toes of the submerged arc welding with experimental results showed the improved beams copes had sufficient deformation capacity. The maximum moment of the welded joint with a conventional or improved configuration was predicted using two evaluating procedures for brittle fractures. A comparison of the connection strengths demonstrated that the improvement in the shape of the weld access holes, and the leg length of welding affected the optimization of the connection details.
|
Free Research Field |
建築構造・材料
|
Academic Significance and Societal Importance of the Research Achievements |
兵庫県南部地震直後には,鉄骨建物の柱梁接合部におけるスカラップ底からの脆性破壊が注目され,震災後,複合円型のスカラップが推奨されたが,その後の研究により,複合円型ではスカラップ底のひずみ集中は緩和されず,脆性破壊に至る可能性が示唆されており,破壊回避策は未だに確立されていない.今後,予想される巨大地震が発生する前に,これを解決した接合部詳細を確立することは,建物の安全性を担保する上で,大きな意義がある.本研究で用いた改良スカラップとウェブの薄肉化(脚長の最小化)により,スカラップ底へのひずみ集中を回避でき,更に梁フィレット部の隅肉溶接止端に沿った延性き裂の進展によりエネルギー散逸が期待できる.
|