Study on Axial Compression Behavior of Concrete Short Columns Confined by Flax/Glass Fiber Hybrid-Reinforced Epoxy Resin Composites.

In this study, we aimed to explore the effect of concrete short columns confined by flax/glass fiber hybrid-reinforced epoxy resin (FFRP/GFRP) composites. Taking the same fiber hybrid ratio and different paving orders as parameters, analysis of the axial compressive mechanical properties of eight groups of FFRP/GFRP composite-confined concrete short columns, including one group of flax fiber-reinforced epoxy resin (FFRP) composite-confined concrete short columns and one group of unconstrained concrete short column, was conducted. The effects of different layering sequences on failure modes, load-displacement curves, energy dissipation ductility and the stress-strain relationship of hybrid composite-confined concrete short columns were analyzed. The results show that the axial compression failure modes of FFRP/GFRP composite-confined concrete short columns with the same hybrid ratio and different paving sequences were basically the same, and the CC-H6 group was the most prominent. The ultimate bearing capacity and axial deflection were 91.05% and 11.49% higher than those of the control group (CC-FFRP), and the energy dissipation coefficient was also the largest, at 9.79. The failure trend of the stress-strain curve of the confined concrete short column specimens was basically the same, and the stress and axial strain of the members were increased by 247.9~292.5% and 486.7~701.0%, respectively.