Axial Hysteresis Behavior with End Restraints

Parametric study of axially loaded steel members with symmetrical rotational end springs (connections) was performed. The main parameters are the connection flexural strength, the effective slenderness ratio, and cross-sectional properties. The rotational end spring is a simulation of the end restraint due to flexural rigidity of the connections of an axially loaded (bracing) member. The member with balanced strength connections, i.e., where plastic hinges form simultaneously at midspan and at the ends, is more efficient with respect to compressive load and energy dissipation capacities than members of the same length and same cross-sectional properties with nonbalanced strength connections. The hysteresis behavior of a balanced strength member can be adequately represented by that of a pin-connected member of the same cross section and same effective slenderness ratio.