IMPROVED SEISMIC PERFORMANCE OF CFT PIERS BY A NEWLY DISCOVERED MECHANISM TO RESTRAIN PROGRESS OF LOCAL BUCKLING DEFORMATIONS

• 後藤 芳顯

  名古屋工業大学大学院 工学研究科社会工学専攻

• 関 一優

  新日鐵住金株式会社 技術開発本部

• 海老澤 健正

  名古屋工業大学 工学研究科社会工学専攻

• 呂 西林

  同済大学 土木工程学院

Bibliographic Information

Other Title

• 地震動下のコンクリート充填円形断面鋼製橋脚における局部座屈変形の進展抑制機構と耐震性向上

Abstract

 Recently, it was found out by authors' numerical analysis that superior performance of CFT piers under unidirectional alternate loading is primarily attributed to a unique behavior that restrains the progress of local buckling deformations in steel tube. Herein, the validity of this behavior under more realistic seismic loads is examined experimentally by carrying out bi-directional shaking table test as well as bi-directional cyclic loading test. From the responses of strains and deformations measured in the cyclic loading test, it was observed that the axial compressive force acting on steel tube is mostly transmitted to the in-filled concrete by diaphragm as soon as local buckling deformation occurs in steel tube. This phenomenon slows down a progress of buckling deformations. Furthermore, under the cyclic loading subsequent to the occurrence of the local buckling, opening and closing of a major horizontal crack along with dilation in the in-filled concrete results in tensile stresses in a locally buckled steel tube. This tensile stresses remove the local buckling bulges by stretching them. From the shaking table test, a remarkable self-centering behavior was observed in CFT piers, although their hysteretic curves are not originoriented. The numerical analysis showed that the unique behavior of CFT piers to remove local buckling deformations occurred during the shaking table test. Therefore, this behavior might have some effect on the self-centering behavior of CFT piers.

Journal

• Journal of Japan Society of Civil Engineers, Ser. A1 (Structural Engineering & Earthquake Engineering (SE/EE))

  Journal of Japan Society of Civil Engineers, Ser. A1 (Structural Engineering & Earthquake Engineering (SE/EE)) 69 (1), 101-120, 2013

  Japan Society of Civil Engineers

Keywords

• CFT column
• thin-walled tube
• local buckling
• self-centering
• diaphragm
• in-filled concrete
• shaking table test

Details

• CRID: 1390282680326785024
• NII Article ID: 130004726590
• DOI: 10.2208/jscejseee.69.101
• ISSN: 21854653
• Text Lang: ja
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed