Stair Stringer - engineered timber and torsion?
Stair Stringer - engineered timber and torsion?
(OP)
Hi All, I am working on some architecturally designed stairs with an architect. The brief is to rely on 1 giant stair stringer to support vertical and torsional loading (from rail and imbalanced live load). It's about 4m long, about 1m wide. I really want to just make it a steel tube but the theme is exposed timber so that's what the Arch wants... I am really hesitant to call-out a glulam or LVL stringer/girder because it seems that the laminations is a weak point for torsion... also I have never seen a timber stringer used in such a way before!
What do you think? Do you have comments on the torsion+vertical loading on say an LVL or Glulam? (obviously steel is the answer but I would like to explore other options....)
Thanks!
What do you think? Do you have comments on the torsion+vertical loading on say an LVL or Glulam? (obviously steel is the answer but I would like to explore other options....)
Thanks!






RE: Stair Stringer - engineered timber and torsion?
PT if they are exterior.
Mike McCann, PE, SE (WA)
RE: Stair Stringer - engineered timber and torsion?
RE: Stair Stringer - engineered timber and torsion?
Then I agree with the steel tube and furring out wood to simulate the wood look.
Mike McCann, PE, SE (WA)
RE: Stair Stringer - engineered timber and torsion?
RE: Stair Stringer - engineered timber and torsion?
RE: Stair Stringer - engineered timber and torsion?
Otherwise, steel it is!
RE: Stair Stringer - engineered timber and torsion?
I'm not sure if the stairs below are wrapped steel but, if they are, they are very convincingly constructed.
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.