NEXCEL Project Paper 40
Release time: 2025/12/23 Publisher： original Views：
Seismic performance of short concrete columns reinforced with steel-FRP composite bars and GFRP stirrups
Prof. Bai Yulei from Beijing University of Technology, Principal Investigator of NEXCEL 2024 SFP project ‘Application and demonstration of FRP tube - concrete new composite structure,’ has published a paper entitled "Seismic performance of short concrete columns reinforced with steel-FRP composite bars and GFRP stirrups" in "Case Studies in Construction Materials" (SCI) recently.
Abstract：
The steel-FRP composite bar (SFCB) is an ideal reinforcement choice for structures aimed at enhancing durability and resilience. However, research on the seismic applications of SFCBs has primarily focused on ffexure-dominated concrete columns, with limited experimental investigation into columns subjected to axial-shear-ffexure interaction. To address this gap, quasi-static tests were conducted on six short concrete columns to evaluate their seismic performance. The study examined the effects of key variables, including longitudinal reinforcement type, the spacing of GFRP stirrups, and shear span-to-depth ratios. The results show that all specimens exhibited a shear-ffexure failure mode. Compared to the steel-reinforced short column, SFCBreinforced short columns with an equal stiffness design method demonstrate better seismic performance, including reduced shear-ffexure damage, similar initial stiffness, higher load-bearing capacity, and increased resilience. Reducing the GFRP stirrup spacing enhances the shear capacity of SFCB-reinforced columns, thereby reducing shear deformation and improving ductility. A decrease in the shear span-to-depth ratio signiffcantly increases the stiffness and overall loaddisplacement curves of SFCB-reinforced columns, with a slight improvement in resilience. An analytical model incorporating axial-shear-ffexure interaction was developed using the uniaxialshear-ffexure model (USFM) approach and validated by comparing the predicted envelope curves with the experimental results.
Paper Details:
Case Studies in Construction Materials 22 (2025) e04703
https://doi.org/10.1016/j.cscm.2025.e04703