Structural property of CFT short columns with shearing failure under cyclic lateral forces

• Project/Area Number: 18K04434
• 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: Nagasaki University
• Principal Investigator: Nakahara Hiroyuki 長崎大学, 工学研究科, 教授 (60315398)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Project Status: Completed (Fiscal Year 2020)
• Budget Amount: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2020: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2019: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2018: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
• Keywords: CFT柱 / CFT指針 / せん断耐力 / 長方形断面 / 正方形断面 / コンクリート充填鋼管 / せん断破壊 / ダイアフラム形式 / CFT指針式 / 局部座屈 / 長方形CFT / 正方形CFT / コンクリート充填鋼管柱

Outline of Final Research Achievements

Test has been conducted for twenty-four CFT specimens under cyclic shearing force and a constant axial force. CFST specimens with two different shapes of sections of rectangle and square were tested. The depth of both sections were 150mm. The a/D ratio of the specimens was 0.6. The yield strength of the steel tube and the compressive strength of the inner concrete was normal strength.
All specimens showed the yielding at the center of the web of the steel tubes and did not attain to the calculated flexural-capacities of CFST columns. The shearing force Q-shear strain γ relationship were investigated. The cyclic behavior of the CFSTs were enough stable to be used as damping devices in seismic regions. From the Q-γ relations, maximum shearing strength was compared to the calculated values by the design formula for CFTs. Those of the experimental results were estimated by the calculated values precisely.

Academic Significance and Societal Importance of the Research Achievements

本研究では，長方形CFT柱と正方形CFT柱の試験体をそれぞれ12体ずつ，合計24体作成し，せん断破壊実験を実施することを計画し，予定通り実施できた．これらは，将来の日本建築学会コンクリート充填鋼管構造の設計施工指針の改訂時における，CFT柱のせん断耐力式の精度検証に必要な実験資料となる．本研究により，コンクリート充填鋼管構造の更なる発展に寄与することができた．

Research Products

• [Journal Article] 異なるダイアフラム形式を有するコンクリート充填鋼管短柱のせん断破壊性状に関する実験的研究 (2021)
  • Author(s): 中原浩之，松竹光太郎，摺木悠人，森下詢太
  • Journal Title: コンクリート工学年次論文集 Volume: Vol43
  • Peer Reviewed
• [Journal Article] 外ダイアフラムを有するコンクリート充填角形鋼管短柱のせん断破壊性状に関する実験的研究 (2020)
  • Author(s): 中原浩之，松竹光太郎，摺木悠人
  • Journal Title: 長崎大学大学院工学研究科研究報告 Volume: Vol.50, No.95 Pages: 35-41
  • NAID: 120006974957
• [Journal Article] 通しダイアフラムを有するコンクリート充填角形鋼管短柱のせん断破壊性状に関する実験的研究 (2019)
  • Author(s): 中原浩之, 池田啓悟
  • Journal Title: 長崎大学大学院工学研究科研究報告 Volume: 48 Pages: 43-49
  • Open Access
• [Presentation] Shearing Behavior of Rectangular and Square Concrete-Filled Steel Tubular Columns (2020)
  • Author(s): Morishita, J., Matsutake, K., Suruki, Y. and Nakahara, H.
  • Organizer: 8th International Symposium on Applied Engineering and Sciences
  • Int'l Joint Research
• [Presentation] Shearing Capacity of Square Concrete-Filled Steel Tubular Columns (2020)
  • Author(s): Suruki, Y., Ikeda, K., Matsutake, K. and Nakahara, H.
  • Organizer: 17th World Conference on Earthquake Engineering
  • Int'l Joint Research
• [Presentation] Estimation Methods for Shearing Capacity of Square Concrete-Filled Steel Tubular Columns (2020)
  • Author(s): Suruki, Y., Matsutake, K., Ikeda, K. and Nakahara, H.
  • Organizer: The 15th Joint Symposium of Nagasaki University and Jeju National University on Science and Technology
  • Int'l Joint Research
• [Presentation] Estimation Methods for Shearing Capacity of Square Concrete-Filled Steel Tubular Columns (2020)
  • Author(s): Y. Suruki, K. Matsutake, K. Ikeda, H. Nakahara
  • Organizer: he 15th Joint Symposium of Nagasaki University and Jeju National University on Science and Technology