Mechanical Behavior of Round-Ended Concrete Columns Reinforced by CFRP–Aluminum Tubes

The mechanical performances of carbon fiber reinforced plastic (CFRP) and aluminum alloy tube reinforced round-ended concrete columns were investigated in this paper. Eight axial compression tests on specimens with circular ends of CFRP–aluminum tubular round-ended concrete columns were designed and made. The axial compression test and theoretical research were carried out. The results show that CFRP improves the confinement of aluminum alloy tube to core concrete, and improves the bearing capacity and ductility of specimens. The maximum axial bearing capacity and ductility of aluminum alloy pipe with the same section size increased by 30.8 % and 43.4 %, respectively. The composite constraint model for calculating the bearing capacity of concrete columns reinforced by CFRP–aluminum tubes is proposed. The calculation results obtained by this calculation method are in good agreement with the experimental values. The model can be used to analyze the axial compression performance of CFRP–aluminum tube reinforced round-ended concrete columns.