Axial Compression Tests for Circular Concrete-Filled Steel Tube (CFST) Columns with Notch Imperfection

The study investigated how simulated notches within concrete-filled steel tube (CFST) columns affect their mechanical performance. It aimed to understand the impact of notch length, orientation, and location within the steel tubes on the behavior of these circular columns. Study conducted compressive tests on a total of 32 CFST specimens, varying in thickness (3 mm and 6 mm) and filled with High-Strength Concrete (HSC) or Normal-Strength Concrete (NSC). Four control specimens without notches served as reference points. Results indicated that CFST columns with notches exhibited reduced mechanical performance compared to those without notches. Notch parameters played a crucial role in this reduced performance. Notch length and orientation had a more significant influence than notch location. It also highlighted that the thickness of the steel tube was a paramount factor, surpassing the importance of concrete type. In summary, the study emphasized that presence of notches in CFST columns significantly impacted their load-bearing capacity, buckling behavior, and failure modes. Length and orientation of notches were identified as critical factors, with steel tube thickness being a dominant factor in determining overall mechanical performance of these columns. These findings provide valuable insights for structural engineers and designers working with CFST columns in various construction applications.