Aluminum Stair Stringers
Aluminum Stair Stringers
(OP)
I have aluminum stair stringers of 16.5ft horizontal length and 11.5ft rise which comes out to ~ 20ft actual length.
The problem is Ohio Grating doesn't want/like us to use the planking as bracing and neither does the engineer who we're subbed out from. From my understanding they're attached with a clip that can't support much load. Without lateral bracing no 12" deep size works. I've attached my Mathcad in case I made a calculation error.
Does x-bracing between the two stringers seem feasible? It doesn't to me. Any ideas/advice?
Thanks
https://www.dropbox.com/sh/jfrolsdh5qwkqoj/Y99KXhb...
The problem is Ohio Grating doesn't want/like us to use the planking as bracing and neither does the engineer who we're subbed out from. From my understanding they're attached with a clip that can't support much load. Without lateral bracing no 12" deep size works. I've attached my Mathcad in case I made a calculation error.
Does x-bracing between the two stringers seem feasible? It doesn't to me. Any ideas/advice?
Thanks
https://www.dropbox.com/sh/jfrolsdh5qwkqoj/Y99KXhb...






RE: Aluminum Stair Stringers
You can always spec a larger section too - a built-up section - the cost of which will go thru the roof. Frequently that begets a more reasonable Architectural design.
Mike McCann
MMC Engineering
RE: Aluminum Stair Stringers
just a thought
Mike Halloran
Pembroke Pines, FL, USA
RE: Aluminum Stair Stringers
Mike - if I understand correctly, that may work. unfortunately I don't think it would fly architecturally.
I emailed Ohio Grating just to double check their stance.
RE: Aluminum Stair Stringers
RE: Aluminum Stair Stringers
RE: Aluminum Stair Stringers
RE: Aluminum Stair Stringers
How much does x bracing the bottom flange help in lateral torsional buckling? Whatever we're x-bracing with would stop the bottom flange from moving laterally, but what would stop the top flange from moving laterally? It'd have to be a moment connection, no?
RE: Aluminum Stair Stringers
Thanks for contacting me. Neither Ohio Gratings nor the other members
of NAAMM Metal Bar Grating Division rate the grating stair treads as
lateral braces for the stringers. Other structural members should be
used for this purpose.
Please let me know if I can be of additional assistance. "
RE: Aluminum Stair Stringers
RE: Aluminum Stair Stringers
Mike McCann
MMC Engineering
RE: Aluminum Stair Stringers
I think I'm going to do welded cross bracing at mid-length. I want it welded to the web below the treads. I just have to make sure it's rigid enough. I just don't think they like to do field welding, and a bolted connection wouldn't be rigid enough... Meh
RE: Aluminum Stair Stringers