Performance of prefabricated RC column with replaceable Column-Base connection under cyclic lateral loads

A new prefabricated RC column with replaceable column-base connection was proposed for moment-resisting frames. The column-base connection was assembled with replaceable steel fuses and padding blocks, which can be easily replaced after an earthquake, to accommodate inelastic deformation. Eight full-scale column specimens were tested to evaluate the effectiveness of various parameters on the seismic performance under lateral loads. The experimental results showed that the column-base connections exhibited stable hysteretic behavior in terms of strength, stiffness and energy dissipation. The lateral load capacity increased with increase in cross-sectional area of steel fuses (1200-1520 mm2) and axial load ratio (0.14-0.24). The seismic performance before and after the replacement of the damaged components was found to be almost identical which indicated that the replaceable column-base connection is feasible and effective. An idealized moment-rotation theoretical model and a simplified 2D nonlinear theoretical model were further developed to predict the flexural response of the proposed columns. Comparison of theoretical model responses with the experiment results showed satisfactory results in predicting the lateral load behavior. Both the models provide a reference for the design procedure and practical applications of the replaceable column-base connection.