Spiral stair design 2

[grandstructures]

I need to design a steel spiral stair
Does anyone have any sample calculations or references
thank you in advance

 

[dik]

If a freestanding spiral, you may not have the torsional stiffness to do it well and it could be bouncy. There's often an impact with people going down stairs. If the treads can be cantilevered from a single vertical in the centre, then the solution is easy. Analysis is easiest with 3D FEM software such as Risa or others.

Dik

 

[boo1]

Consider this reviewing page 11

http://www.stairways.org/pdf/2006 Stair IRC SCREEN.pdf

or

http://www.salterspiralstair.com/steel.htm

 

[normm]

Are you planning to have a post in the middle, or curved stringers only?
If stringers, are you planning a single stringer in the middle or 2 stringers under the handrails?

 

[grandstructures]

yes there will be a post in the middle

 

[connectegr]

We frequently design spiral stairs. In most cases we model the stairin order to accurately determine the loading, including torsion on the stringers. You will find that most of the design examples available do not apply well to curved members.

http://www.FerrellEngineering.com

 

[dik]

If a post in the middle, there are several 'pre-fabbed' proprietary systems available.

Dik