Longitudinal steel does not contribute to the stiffness matrix of reinforced-concrete frame elements, though it does, however, contribute to the following sources:
- Cross-section design using parameters available through the Design menu;
- Fiber-hinge response under inelastic behavior; and
- Moment-curvature relationships obtained through the Section Designer.
Property modifiers are available to users who wish to change the elastic stiffness of a reinforced-concrete frame-element cross section.
