Path-dependent cyclic stress–strain relationship of reinforcing bar including buckling

In this paper, the formulation and verification of a cyclic stress–strain relationship of reinforcing bars are presented. The tension envelope comprises an elastic range, a yield plateau and a hardening zone. The compression envelope also includes a linear elastic range followed by a non-linear buckling model. The cyclic loops follow Giuffre–Menegotto–Pinto equations with some modifications to account for the effect of buckling. A complete path-dependent cyclic constitutive model is then obtained by combining the equations representing the two monotonic envelopes and the cyclic loops. Comparison with bare bar test results shows that the proposed model could reasonably predict the cyclic behaviour of reinforcing bars including the post-buckling loops.