The contribution of the reinforcement is not considered in the stiffness matrix of concrete frame elements. However, the reinforcement specified for frame cross-sections is used for the following purposes:
- Design of the concrete frame cross-section via the commands available in the "Design" menu.
- Response of fiber hinges based on the given section.
- Moment-curvature relationship for reinforced concrete sections can be obtained in section designer, considering the contribution of the reinforcement.
To change the elastic stiffness of concrete frame cross-sections, you can apply frame section property modifiers.
