Simulation of Seismic Behavior for RC Columns under Bidirectional Compression-Bending

Abstract

To investigate the seismic behavior of RC columns under bidirectional lateral loading, numerical analysis for tests of RC columns under biaxial loading were performed using fiber model. The simulation results agreed well with test results. The effect of axial compression ratio on the seismic behavior of RC columns under biaxial lateral load was analyzed. The analytical results showed that biaxial lateral loading had little effect on critical axial compression ratio, and the value of critical axial compression ratio was between 0.4~0.5. Bevel carrying capacity under bidirectional lateral loading was a little greater than that under principal axial loading when axial compression ratio was less than 0.1. There had been about 10 percent decrease in bevel carrying capacity at critical axial compression ratio but principal axial bearing capacity declined about 35 percent. Moreover, ultimate displacement angle and accumulative hysteretic dissipation energy decreased observably with increase of axial compression ratio. The adverse influence of special effect on principal axis should be considered in the actual design.