EXPERIMENTAL STUDY ON SEISMIC PERFORMANCE OF STEEL REINFORCED RECYCLED CONCRETE SHORT COLUMN UNDER LOW-CYCLIC REVERSED LOADING

Through eight column specimens with various replacement rates of recycled coarse aggregate, axial compression ratios, stirrup ratios were tested under low cyclic reversed loading. The failure process and pattern were observed. The mechanical behaviors such as load-displacement hysteretic loops and skeleton curves, load carrying capacity, ductility, energy dissipation capacity and stiffness degradation of steel reinforced recycled concrete short columns were analyzed. Test results show that the failure pattern of steel reinforced recycled concrete short columns is the shear diagonal compression failure. The load-displacement hysteretic loops of specimens can be approximated as a spindle shape. After the peak load, the load carrying capacity decreases rapidly, while the deformation is small and the ductility or energy dissipation capacity is poor. With the replacement rate of recycled coarse aggregate increase, there is no obvious influence for the load carrying capacity of specimens, while the ductility or energy dissipation capacity reduces somewhat. With increase of axial compression ratio of the specimens, the load carrying capacity increase, while the ductility or energy dissipation capacity reduces a lot. The load carrying capacity and ductility or energy dissipation capacity of specimens increase with the stirrup ratio increase. Except for the short column with a small axial compression ratio, the ductility factors of the other short columns are less than 3, showing that the seismic performance of steel reinforced recycled concrete short columns is poor. Therefore, certain measures are necessary for improving the seismic performance of steel reinforced recycled concrete short columns in the practical engineering.