Seismic performance of recycled aggregate concrete-filled glass fibre-reinforced polymer-steel composite tube columns

Recycled aggregate concrete (RAC) has attracted increasing attention over the past decades due to its sustainable development in the environment, society and economy. However, compared with natural aggregate concrete (NAC), the mechanical performances of RAC involving the strength, stiffness, and durability are poor, limiting the application of RAC. In this paper, RAC-filled glass fibre-reinforced polymer (GFRP)-steel composite tube columns, which can overcome the shortages of RAC, was proposed. A systematic experimental study was conducted to investigate the seismic performance of RAC-filled GFRP-steel composite tube columns, in which the FRP on the steel tube is manufactured through a filament-winding process. Different aspect ratios and axial compression ratios were considered for these columns. Their failure modes, lateral moment-drift hysteretic responses, skeleton curves, energy dissipations, stiffness degradations and equivalent viscous damping ratios were discussed in detail. It is showed that compared with RAC-filled steel tube columns, RAC-filled GFRP-steel composite tube columns exhibited a superior seismic performance, especially for the ductility factor. Finally, an empirical model was developed to predict the lateral moment-drift skeleton curves of RAC-filled GFRP-steel composite tube columns. The findings can expand the application of RAC and provide a seismic design guidance of RAC-filled GFRP-steel composite tube columns. (C) 2019 Elsevier Ltd. All rights reserved.