I don't see the relationship. I would have consider the second paragraph as
only limiting the total deflection to a life safety limit, however all
subsequent sections in Chapter 16 narrow down the analysis of the diaphgam
and set a stricter limit based upon calculations. All this tells me is than
no diaphgragm can be allowed to deflect past the point where life safety is
at issue. And, this section does not state explicity that the diaphragm can
not be rigid.
Neil pointed me to the indext where it clearly states that section 2315.1 of
the 97UBC refers to "Not acceptable as rigid diaphragm". However, this
statement does not appear in the actual code section unless there is an
erratta that I do not have that has added it.
Any other comments to help make this clear?
Dennis S. Wish PE