An experimental program is presented to determine the behaviour of steel beam-columns under elastic and inelastic moment reversal. Two beam-columns were tested to obtain moment-thrust-curvature relationships under moment reversal into the inelastic range of the material, with different deflections at the beginning of moment unloading. Substantial agreement was reached with the results of other researchers.

A computer program has been developed to obtain horizontal load versus maximum deflection relationships for beam-columns under single moment reversal. Although the computed behaviour agrees in its general characteristics with the experimental results, there is room for improvement in this agreement.