Ductility check is performed in accordance with 8.1.5. For sections with M*
> 0.8φMuo, a ductility design is performed to limit
kuo to ≤ 0.36. For sections with M*≤
0.8φMuo no ductility check is performed but if
kuo is larger than 0.36 an appropriate capacity reduction factor φ is
calculated from Table 2.2.2.
M* is determined from load combinations associated with ductility design rules only.
It is recommended that the same load combinations be assigned to strength and
ductility design to keep this check consistent.
Section 8.1.5(a) and 8.1.5(b) are not implemented
If the reinforcing bar covers are such that the compression bar is outside of the
0.36d zone, then a solution may not be possible.
In certain circumstances it may not be possible to simultaneously provide positive
moment ductility and negative moment ductility. This most commonly happens if there
is a large post-tensioning tendon near the center of the cross section.
