The growing demand for durable and corrosion-resistant concrete structures has led to significant interest in Fiber-Reinforced Polymer (FRP) bars as a viable alternative to conventional steel reinforcement. However, the linear-elastic nature of FRP bars combined with the inherent brittleness of plain concrete frequently results in brittle, catastrophic failures under axial compression. To mitigate these limitations, this study presents a comprehensive three-dimensional (3D) numerical investigati