Experimental study and novel design‐oriented approaches for strengthening recycled brick aggregate square concrete columns with basalt <scp>FRP</scp>

Abstract This study uniquely examines the effectiveness of basalt fiber‐reinforced polymer (BFRP) wraps in enhancing the mechanical properties of recycled brick aggregate concrete (ReBAC) square concrete columns, using both fired clay solid and hollow brick aggregates. This combination is relatively unexplored in existing literature. Furthermore, this study promotes waste reduction and resource efficiency, minimizing the environmental impact of concrete production. A total of 64 square concrete specimen types were employed in this work. The magnitude of BFRP confinement was increased by two, four, or six layers. The natural coarse aggregates were replaced by 50% or 100% recycled brick aggregates. Two types of bricks were considered, that is, fired‐clay solid or fired‐clay hollow bricks. The results demonstrate that BFRP wraps significantly improve the compressive strength by up to 130.76% and ultimate strain by up to 1800%, with higher improvements observed in concrete made with CBB bricks due to their superior compressive strength and lower water absorption. The confinement effect, which becomes active only after significant axial deformation, is positively influenced by the number of wraps, with the confinement ratio emerging as a key parameter for strength and strain improvements. The study also presents regression‐based design‐oriented models for the compressive behavior of BFRP‐confined ReBAC, showing good correlation with experimental results and highlighting the importance of aggregate properties in analytical modeling. The findings suggest that BFRP is an effective and sustainable solution for strengthening ReBAC, with potential for use in structural applications.