External CFRP cord beam-to-column joint reinforcement
Research output: Contribution to journal › Research article › Contributed › peer-review
Contributors
Abstract
CFRP cords utilized as external concrete reinforcement follow the curvature in flexural deformation due to their flexibility, preventing debonding that occurs with pre-pregnated CFRP bars. This study investigated the CFRP cord utilization for revitalizing cracked, non-collapsed haunch beam-to-column joints through experimental and numerical methods on large-scale specimens, enhancing the direct applicability of the findings to real-world structures. Since tensile reinforcement has yielded, the cords took a substituting role in the energy dissipation and ductility refinement, restoring the integrity of the system. Two members with haunch angle variations were loaded until tensile-steel yielding, straightened, and epoxy injection retrofitted. Three CFRP cords were attached to the tensile area, and the member was reloaded. The rehabilitation effectiveness was performed by comparing the behavior to two uncracked interchangeable members. A numerical model was developed, and a multi-criteria sensitivity analysis was conducted to evaluate the shifting of the most significant failure behavior parameters. It was demonstrated that the concrete ultimate strain and the initial and post-crack stiffness modulus in compression were the most influential factors, while for non-CFRP-reinforced identical members, the residual stress coefficient and ultimate stress in tension were dominant. The reinforced member was restored and improved significantly in terms of load-carrying capacity of 27% and 32% for 14∘ and 26.5∘ haunch, respectively, with the reduced initial stiffness of 30–67%. The findings provide validated, practical strategies for engineers seeking to extend the service life of existing concrete infrastructure, moving beyond laboratory-scale proof of concept to demonstrate a viable and effective conservation technique.
Details
| Original language | English |
|---|---|
| Article number | 320 |
| Journal | Materials and Structures/Materiaux et Constructions |
| Volume | 58 |
| Issue number | 10 |
| Publication status | Published - Dec 2025 |
| Peer-reviewed | Yes |
Keywords
ASJC Scopus subject areas
Keywords
- CFRP cords, Epoxy retrofitting, Geopolymer haunch, Multi-criteria sensitivity analysis, Rigid body spring model