Experimental study on seismic performance of steel reinforced concrete T-shaped columns

This study investigates the seismic performance of steel reinforced concrete (SRC) T-shaped columns under low cyclic loading tests. Based on test results of ten half-scale column specimens, failure patterns, hysteretic behavior, skeleton curves, ultimate strength, ductility, stiffness degradation and energy dissipation capacity were analyzed. The main variables included loading angles, axial compression ratios and steel ratios. The test results show that the average values of the ductility factor and the equivalent viscous damping coefficient with respect to the failure of the columns were 5.23 and 0.373, respectively, reflecting good seismic performance. The ductility decreased and the initial stiffness increased as the axial compression ratio of the columns increased. The strength increased with increasing steel ratio, as expected. The columns displaced along the web had higher strength and initial stiffness, while the columns displaced along the flange had better ductility and energy dissipation capacity. Based on the test and analysis results, a formula is proposed to calculate the effective stiffness of SRC T-shaped columns.