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Is it possible to share your experience about how to comply with the
following design code?

	2227.1 Connections (1997 UBC). Adequate strength of connections
to withstand calculated resultant forces and moments, and adequate
rigidity where such is required, shall be demonstrated by calculation or
by testing in an approved manner.

It can be seen from the code that a connection has two requirements:
"(1) sufficient strength for forces and moments" and "(2) adequate
rigidity".

Requirement "(1) sufficient strength for forces & moments"......
There is no problem with the first requirement. Most structural software
can analyze the required forces and moments for structural professionals
to design connections.

Requirement "(2) adequate rigidity"....
If you have design experience, is it possible to show how you comply
with the second requirement? If your structural software cannot provide
any information about the minimal (required) connector stiffness, how do
you make sure your design has an adequate rigidity to comply with the
code?

Most structural analysis assumes each connection has a perfect rigidity
(stiffness=infinity), and outputs a set of connection forces and
moments. In other words, those forces and moments are valid only if the
connector stiffness is infinite. There is no way to design a connection,
for example, steel connection, to have an infinity stiffness. If your
connection design does not provide a sufficient large stiffness, all the
internal forces and moments must be redistributed. Safe or not? A safe
design must provide an adequate rigidity for connections. Is it possible
to share you experiences about how to comply with the second
requirement? Thank you.


wd