FRP-钢夹层复合管混凝土桥墩轴压承载力试验

To improve the corrosion resistance of concrete-filled steel tubular column (CFST) and construction inconvenience of FRP-steel tube concrete column (FSCC), a novel composite member is proposed, namely, FRP-interlayer-steel tube concrete column (FIST). In this paper, axial compression tests on FIST, FSCC and CFST were conducted to investigate the failure modes and the loading process. The experimental results indicated that the failure mode of FIST and FSCC was waist drum failure owing to the confinement of FRP, which is different from the shear failure mode of CFST resulting from low steel ratio. Compared with FSCC, whose resin matrix was crushed, FIST avoided this due to the existence of the interlayer. The bearing capacity and ultimate deformation of FIST increased by 35.3% and 22.5% respectively, higher than that of FSCC also owing to the interlayer. The design equation of the bearing capacity of FIST was proposed from the equations of the bearing capacity of CFST and FSCC. Calculations and test results showed good agreement.