round hss

huangyhg

round hss
do you know why on aisc(i only have 3rd edition lrfd) in the column section, they only have round hss until 4" diameter?  after that they call it standard pipe.  how do i get the axial values for maybe 3 1/2" diameter x 3/16 hss?  is it typical to spec 3 1/2" standard steel pipe?
never, but never question engineer's judgement
i don't know - the table commentary at the front doesn't mention anything and the smaller hss sizes do exist (see page 1-72).
i have a couple of exposed column and the owner wants a round column.  i am afraid if i put standard steel pipe, the contractor may use a plumbing steel pipe or something.  but then again i dont have the design value for anything lower smaller than 4".  i dont want to specify a 4" column, i think it doesnt look very good.  3" would be perfect.
never, but never question engineer's judgement
can you just calc the allowable axial capacities?  the values in those tables are pretty easy to come up with.
i guess i'll do that.  i still dont understand why they dont list the rest of th hss though.
never, but never question engineer's judgement
why don't they list the smaller round hss sizes?  why do they occassionally remove w8 columns from the tables?  to save room in the manual, and to discourage the use of certain shapes for various applications.