Inelastic Buckling Behavior of Concrete Reinforcing Bars Under Monotonic Uniaxial Compressive Loading

The main objective of this research is to expand the experimental information available on the buckling behavior of longitudinal reinforcement. Compression tests on well-instrumented bars are performed and axial and lateral deformations are reported herein. To establish a constitutive relationship for reinforcing bars under axial compression, an experimental study on 108-#8 and 54-#10 reinforcing bar specimens having unsupported length to bar diameter ratios (L/d) ranging between 4 and 12 and mid-span eccentricity to bar diameter ratio (e/d) between 0.0 and 0.5 was conducted. In addition, #8 and #10 bars with different material properties were tested to investigate the influence of strain hardening response on the post-buckling behavior of reinforcing bars. Finally, the results obtained are comparatively studied, and the effects of e/d ratio, L/d ratio, and material properties on reinforcing bar behavior are evaluated.