In moment resisting frames beams and columns are designed for flexural, axial, and shear actions due to vertical
and horizontal loads. Special proportioning and detailing requirements are applied in these elements for making
them capable of resisting against severe earthquakes without significant loss of strength beyond the flexural elastic
limit, and avoiding brittle failure (shear mechanisms). As known, the required flexural inelastic excursions
(expressed by the local ductility demand) depend on the dissipative capacity of the structure. The flexural ductility
significantly increases with the transverse reinforcement amount provided to confine section core and to prevent
buckling of compressed longitudinal bars.
In this paper detailing provisions adopted by some seismic codes are compared. At first, the codes provisions to be
applied within critical regions of RC primary frames sections are discussed and compared as a function of the
curvature ductility demand. Then, non-linear monotonic moment-curvature analyses are performed on fiber
sections of columns and beams, and by taking into account the confinement effects on concrete core as well. The
numerical investigations are carried out for comparing the available curvature ductility with the expected one
applying the provisions mentioned by the seismic codes
