Seismic behavior of steel reinforced ECC columns under constant axial loading and reversed cyclic lateral loading

The seismic performance of steel reinforced engineered cementitious composite (RECC) short columns was investigated in this study. RECC columns with various shear span-to-depth ratios, axial load levels and transverse reinforcement ratios, together with one control reinforced concrete (RC) short column, were tested under the combined action of constant axial loading and reversed cyclic lateral loading. Test results indicate that RECC columns are superior to RC columns in terms of ductility, energy dissipation capacity and damage tolerance. The control RC column and the RECC column with the smallest shear span-to-depth ratio (of 1.42) were found to fail in shear. All other RECC columns, with higher shear span-to-depth ratios, including one RECC column without stirrups, failed in a flexure-dominated manner. Furthermore, theoretical flexural strength and shear strength expressions of RECC columns were derived and validated by the test results.