Axial Compression Behavior of <scp>TRU</scp> ‐Reinforced Plain Concrete Columns

ABSTRACT This study explored the axial compression behavior of textile‐reinforced ultra‐high toughness cementitious composite (TRU) reinforced plain concrete columns. A total of 14 specimen groups were tested to investigate parameters including textile type, layer number, fillet radius, reinforcement thickness, lap length of textile, and core column cross‐sections. In particular, the influence of the fillet radius on the constraint effect was emphasized. Results showed that carbon textile outperformed glass and basalt, and positive correlations were found between the axial compressive strength of TRU‐reinforced plain concrete columns and textile layers, fillet radius, reinforcement thickness, and lap length of textile. Rectangular columns had the highest axial compressive capacity, followed by square, then cylindrical. Based on the stress–strain curve, a compressive constitutive model for TRU‐reinforced concrete was proposed. Additionally, a finite element model for square TRU‐secured ordinary concrete columns was established, which has good accuracy and applicability. Theoretical ultimate compressive strength and ultimate axial compressive capacity formulas for square TRU‐reinforced plain concrete columns were derived, aligning with test and simulation results, providing a theoretical and practical foundation for future research. The study revealed the fillet radius's optimization mechanism on stress distribution, advancing cross‐sectional design and filling theoretical gaps in TRU‐reinforced square columns.