Effect of multiaxial strain amplitudes on the cyclic behavior for SN490B steel under proportional loading

Abstract

SN490B is used in main steel members of high-rise buildings. In this study, multiaxial cyclic tests were conducted on SN490B under a combination of axial tension, compression, and torsion. For a strain amplitude of εa = 0.3%, cyclic softening behavior was observed regardless of multiaxiality. The cyclic softening converged after approximately 100 cycles. However, no significant cyclic softening was observed at εa = 0.5%. The stress variation is expressed as a function of plastic strain. The stress variation equation developed for the cyclic softening and hardening behavior of SN490B accurately approximated the test results.