Seismic performance of steel-reinforced recycled concrete columns under low cyclic loads

This paper describes an experimental study of the seismic performance of steel-reinforced recycled concrete (SRRC) columns. Based on low cyclic loading tests of seven 1:2.5-scaled column specimens, the failure modes, hysteresis loops, skeleton curves, ductility, energy dissipation capacity, and stiffness degradation of SRRC columns were analyzed. The influence of recycled coarse aggregate (RCA) replacement percentages, axial compression ratios, and stirrup ratios on the seismic performance of SRRC columns was investigated in detail. The test results show that the seismic performance of SRRC columns decreases slightly as the RCA replacement percentage increases. The results also indicate that appropriate design of the axial compression ratio and stirrup ratio can improve the seismic performance of SRRC columns. The average values of the ductility factor and the equivalent viscous damping coefficient with respect to the loop of ultimate load of the columns were 3.47 and 0.217, respectively, which reflect the SRRC columns' good performance in terms of earthquake resistance.