Please allow me one question:
How safe is to use liberal stress when you expect occasional loads?
At first view no link betwen the two, but......
Para. 302.3.5 Limits of Calculated Stresses Due to Sustained
Loads and Displacement Strains
(d) Allowable Displacement Stress Range, SA
When Sh is greater than SL, the difference between
them may be added to the term 0.25Sh in eq. (1a). In
that case, the allowable stress range is calculated by
eq. (1b): SA =f[1.25(Sc + Sh) − SL] (1b)
...and the code allow you to use the extra for secondary stress
Para. 302.3.6 Limits of Calculated Stresses Due to Occasional
Loads
(a) Operation. The sum of the longitudinal stresses,
SL, due to sustained loads, such as pressure and weight,
and of the stresses produced by occasional loads, such
as wind or earthquake, may be as much as 1.33 times
the basic allowable stress given in Appendix A.
....assume that you already decided to use liberal stress.
Any concern?
Do we artificially increase the allowables?
Or is fair to assume that you can use the liberal stress when you do not expect occasional events.
Best regards,
Dan
_________________________
Dan