Axial Loading Behaviors and ACI 440 Code Applied Ultimate Axial Strength Formula of CFRP Strengthened Circular CFT Columns

탄소섬유쉬트로 보강된 원형CFT기둥의 압축거동과 ACI 440 code를 응용한 압축내력예측식 제안

Park, Jai-Woo;Hong, Young-Kyun;Choi, Sung-Mo

  • Received : 2011.01.02
  • Accepted : 2011.03.02
  • Published : 2011.03.31


This study investigates the axial behavior of CFRP strengthened circular CFT columns and proposes the design formula of CFRP strengthened circular CFT columns. 10 specimens were prepared and axial loading test were conducted to investigate the retrofitting effects of CFRP composites on CFT columns. The main parameters are the number of FRP sheets and D/t ratio. Test results showed that the CFRP retrofitting enhanced the load bearing capacity of the circular CFT columns. Finally, A ACI 440 code applied ultimate axial strength formula is proposed to predict the ultimate strength of CFRP strengthened circular CFT columns. The proposed formula are good agreement with the test results.


concrete filled steel tube;CFT;FRP;strengthening


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Supported by : 한국과학재단