3. If it is
not designed, it cannot be pushed.
•E, I, and A are not sufficient.
•Push-over characteristics are strong functions of
force-displacement characteristics of
individual members and their connections.
• If detailed
characteristics are not known, the push-over analysis will be an exercise in futility.
•Examples:
–Force-deformation properties of R/C are vastly different
from that of steel and care should be taken
to determine the initial stiffness, the cracking and the yielding moments and also the post yield
behavior.
–For steel structures, the moment curvature is primarily
bilinear or trilinear
–The possible failure mechanisms in the joint panel zones
should be considered in the analysis.
– Possible
premature weld fractures at the joints will prevent adjoining members from achieving their full plastic capacities. If
such fractures are anticipated, they should
be given their due consideration.
