Experimental Study on the Residual Axial Load-Carrying Capacity of Shear-Damaged RC Columns

抄録

This study conducts an experimental program to calibrate a proposed arch resistance model that can be used to evalu-ate the residual axial load-carrying capacities of shear-damaged reinforced concrete (RC) columns. An extreme dam-age pattern of shear-damaged RC columns in which the axial load is carried by the longitudinal bars only due to spalling of the concrete core is considered in the experimental program. To simulate this extreme damage pattern, five bare specimens with different clear lengths are fabricated using only steel bars and tested to axial collapse under different axial loads. Based on the experimental results, the force-displacement behavior, limit state of the axial collapse, and stress state of the longitudinal bars of the shear-damaged RC columns are investigated for the proposed arch resistance model. The ratios of the analytical to the measured residual axial capacities in the designed specimens are between 0.77 and 0.92, demonstrating the high accuracy of the proposed model. In addition, the effects of post-yield strain hardening of the longitudinal bars on the force-displacement behavior and on the accuracy of the residual axial capacities of the shear-damaged RC columns are discussed.