Steel-reinforced concrete joints under reversal cyclic load

The performance of structural joints comprising built-up steel-reinforced concrete (SRC) columns connecting to reinforced concrete (RC) beams under reversal cyclic loads is described in this paper. Eight composite joint specimens were tested to failure. Three modes of failure, namely, bending failure in beam, bending–shear failure in beam and shear failure in beam and joint were observed. Test results indicated that energy dissipation capacity of the SRC joint depends on the modes of failure and the levels of axial load imposed on the column. The higher the level of axial force imposed on the column, the lower the energy dissipation capability but the larger shear capacity of the joint. An analytical model for the evaluation of the shear capacity of SRC joint taking into account the effects of the presence of steel section, stirrups, axial force in column and ductility demand is proposed. Analytical and experimental results show good agreement.