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

Abstract

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.

Keywords

• hybrid FRP composites
• short concrete columns
• axial compression
• ultimate bearing capacity