Shear behavior of steel reinforced concrete column-steel beam joints with or without reinforced concrete slab

As one of the key parts of a frame structure, joints are usually subjected to large shear forces under seismic loads. The calculation of joint shear capacity is an essential step in seismic design. In this paper, the existing calculation methods for shear capacity of steel reinforced concrete (SRC) column-steel beam joints from different standards were studied and compared in detail. Quasi-static cyclic tests were conducted on six SRC composite column-steel beam joint specimens with or without reinforced concrete (RC) slab. The corresponding shear capacities were calculated based on the stress mechanism of the joints, and several existing calculation methods were compared. The main design parameters in the tests were axial compression ratio and concrete slab width. Results showed that the shear capacity of the joints increased with an increase in the axial compression ratio. The addition of X-reinforcement had little effect on the shear capacity of the joints, while an RC slab could greatly increase the shear capacity of the joints. Finally, the formula for the shear capacity suggested by Chinese standard of JGJ138-2016 was improved to consider the effect of RC slabs on capacity of the SRC column-steel beam joints through finite element analysis. The modified formula was proven to be effective and feasible in engineering practice.