Compressive behavior of concrete-filled FRP tube columns: Assessment of critical column parameters

Behavior of square and rectangular ultra high-strength concrete-filled FRP tubes under axial compression

“…The use of HSC/ UHSC for CFFTs is attractive because the efficient combination of two high strength materials (i.e., HSC/UHSC and FRP) leads to highperformance columns that exhibit highly ductile behavior as was demonstrated in Ozbakkaloglu and Saatcioglu [20,21] and Idris and Ozbakkaloglu [23]. However, just like the research on square and rectangular CFFTs, the research on the axial compressive behavior of higher strength concrete-filled FRP tubes have been very limited with only two studies reported to date on circular [17,33] and one on square and rectangular HSC or UHSCFFTs [15]. The above summary of the current state of the literature clearly demonstrates the need for additional experimental studies on HSC and UHSCFFTs in general and square and rectangular HSC and UHSCFFTs in particular.…”

“…[2][3][4][5][6][7][8][9][10]). However, the majority of these studies focused on FRPwrapped specimens and studies examining the behavior of CFFTs remain limited [11][12][13][14][15][16][17]. Nonetheless, these early studies on the compressive behavior of CFFTs together with a few studies reported on the seismic behavior of CFFT columns [18][19][20][21][22][23] have demonstrated the ability of CFFTs to develop very high inelastic deformation capacities, which makes them a highly attractive alternative for construction of new high performance columns.…”

Axial compressive behavior of FRP-confined concrete: Experimental test database and a new design-oriented model

“…[3,4,8,9,11,[15][16][17][18][19][20][21][22][23][24][25]). Several causes have been given for the observed differences between hoop rupture strains and material ultimate tensile strains, including: (i) the quality of workmanship; (ii) overlaps of fiber sheets in the FRP shell; (iii) manufacturing imperfections (e.g., misalignment of fibers); (iv) shrinkage of the concrete (for FRP tube-encased concrete); (v) localized or non-uniform effects caused by imperfections in FRP shells and/or heterogeneity of cracked concrete; (vi) load eccentricities caused by specimen imperfections and/or test setup imprecisions; (vii) multiaxial stress condition generated on the FRP shell; and (viii) effect of the curvature of the FRP shell.…”

Factors Influencing Hoop Rupture Strains of FRP-Confined Concrete

“…These factors include: (i) the differences in methods of measurement and test apparatus, and (ii) differences between FRP jackets and flat coupons caused by workmanship, geometric imperfections, residual strains, shrinkage incompatibility, non-uniform bond between concrete and FRP, curvature of the FRP jacket, multiaxial stress state in the FRP jacket. In addition to these, the strength of concrete and the elastic modulus of FRP material have recently been identified by the authors as two important material dependent factors [8,12,[16][17][18][19][20]. However, additional targeted investigations are required to gain a clearer insight into the influence of these factors on the hoop rupture strains of FRP jackets.…”