Analysis on axial compressive performance of the concrete filled square CFRP-steel tubes (S-CFRP-CFST)

作者：Wang Qing Li^*; Che Yuan; Ye Mao

来源：Journal of Harbin Institute of Technology, 2012, 44(SUPPL.1): 43-50.

• Concrete filled square CFRP-steel tubular
• Load-bearing capacity
• Static performance
• Stub columns
• Theoretical analysis

Analysis based on finite element showed that, the transverse stress of the steel tube of the axially compressed concrete filled square CFRP-steel tubular (S-CFRP-CFST) stub columns increases as the distance from the specimen end plate increases, whereas the longitudinal stress of the steel tube keeps almost constant and the stress at the corner of the concrete is the maximum. The confined effect of the outer tube to the concrete is mainly focused on the corners. Before fracture, CFRP can improve the stiffness of the specimen effectively, and thus the deformation of the specimen is deferred. In the initial loading stage, the outer tube has no confined effect on the concrete. The confinements along the side of the cross-section and the height of the specimen are both not uniform. The average confined force can be increased by both increasing the confinement factor and the concrete strength. The adhesive strength has little effect on the load-strain curves and on the confined force-strain curves. With the increasing of the initial stress in the steel tube, the load bearing capacity of the specimen decreases, and the stiffness also drops a little. Accordingly, the peak value of the average confined force is also reduced. Equation for calculating the load bearing capacity of the composite stub columns is presented, and the estimated results agree well with the experimental results.

• 出版日期2012