FRP-confined circular concrete-filled steel tubular columns under cyclic axial compression

Abstract Concrete-filled steel tubes (CFTs) are widely used as columns in many structural systems. In CFTs, inward buckling deformations of the steel tube are prevented by the concrete core, but degradation in steel confinement, strength and ductility can still result from outward local buckling. To overcome this deficiency of CFTs, CFTs can be confined with fibre-reinforced polymer (FRP) wraps to suppress outward local buckling deformations. This paper is concerned with the behaviour and modelling of FRP-confined concrete-filled steel tubular columns subjected to cyclic axial compression. Results from two series of cyclic axial compression tests on CCFTs are presented and discussed. A cyclic stress–strain model for confined concrete in CCFTs is also proposed and is shown to compare well with the test results. The proposed stress–strain model can be employed in the modelling of CCFTs under seismic loadings in future studies.

[1]  J. Teng,et al.  Stress–strain model for FRP-confined concrete under cyclic axial compression , 2009 .

[2]  B. Sinha,et al.  STRESS - STRAIN RELATIONS FOR CONCRETE UNDER CYCLIC LOADING , 1964 .

[3]  Tao Yu,et al.  FRP-confined circular concrete-filled thin steel tubes under axial compression , 2011 .

[4]  Gu Wei Experimental study on concentrically-compressed circular concrete filled CFRP-steel composite tubular short columns , 2004 .

[5]  James O. Jirsa,et al.  Behavior of concrete under compressive loadings , 1969 .

[6]  Yueming Hu,et al.  Behaviour and modelling of FRP-confined hollow and concrete-filled steel tubular columns , 2010 .

[7]  Yan Xiao,et al.  FRP-confined concrete under axial cyclic compression , 2006 .

[8]  C. Hsu,et al.  STRESS-STRAIN BEHAVIOR OF CONCRETE UNDER CYCLIC LOADING , 1998 .

[9]  Kazuhiko Kawashima,et al.  Unloading and Reloading Stress–Strain Model for Confined Concrete , 2006 .

[10]  Lin-Hai Han,et al.  Axial Loading Behavior of CFRP Strengthened Concrete-Filled Steel Tubular Stub Columns , 2007 .

[11]  Yan Xiao,et al.  Confined Concrete-Filled Tubular Columns , 2005 .

[12]  Jai Woo Park,et al.  Behaviors of concrete filled square steel tubes confined by carbon fiber sheets (CFS) under compression and cyclic loads , 2010 .

[13]  Tao Yu,et al.  Stress–strain model for concrete in FRP-confined steel tubular columns , 2013 .

[14]  Ralejs Tepfers,et al.  Experimental investigation of concrete cylinders confined by carbon FRP sheets under monotonic and cyclic axial compressive loads , 2002 .

[15]  Yan Xiao,et al.  Seismic behavior of confined square CFT columns , 2006 .

[16]  Giorgio Monti,et al.  Nonlinear Cyclic Behavior of Reinforcing Bars Including Buckling , 1992 .

[17]  Jg Teng,et al.  Theoretical model for FRP-confined circular concrete-filled steel tubes under axial compression , 2006 .

[18]  Y. Xiao,et al.  Applications of FRP Composites in Concrete Columns , 2004 .

[19]  Lan Liu,et al.  Axial bearing capacity of short FRP confined concrete-filled steel tubular columns , 2010 .