Free standing stair
Free standing stair
(OP)
Folks:
I am in the process of analyzing/designing my first floating stair and could use your inputs/wisdom as I try to understand behavior.
My starting point is a cantilevered truss frame with tension (top flight) and compression (bottom flight). Then the flights get separated by a distance to create the stair.
Before I try to model it or get "fancy", I want to really understand the working of it. See attached cartoon sketch for what I think are the various forces/moments that act on it. Chances are that I am missing some more.
I would appreciate if you could share your insights from previous similar stairs you designed and suggest ways to analyze/detail it.
I am in the process of analyzing/designing my first floating stair and could use your inputs/wisdom as I try to understand behavior.
My starting point is a cantilevered truss frame with tension (top flight) and compression (bottom flight). Then the flights get separated by a distance to create the stair.
Before I try to model it or get "fancy", I want to really understand the working of it. See attached cartoon sketch for what I think are the various forces/moments that act on it. Chances are that I am missing some more.
I would appreciate if you could share your insights from previous similar stairs you designed and suggest ways to analyze/detail it.






RE: Free standing stair
I do not agree that the landing acts as a support.
RE: Free standing stair
Yes, you are right. There will be moments at the interface of landing/flight.
What would be the best way to approach this? It is a concrete stair.
RE: Free standing stair
The top and bottom landings will certainly have a bending component that will make its way into the top and bottom stringers.
Should be an easy model to make.
RE: Free standing stair
This behavior should give you a better understanding of how to model the real structure.
Michael.
Timing has a lot to do with the outcome of a rain dance.
RE: Free standing stair
Good Luck and nice to see this type of work happening...
Dik
RE: Free standing stair
Dik
RE: Free standing stair
RE: Free standing stair
RE: Free standing stair
A four member rigid frame with pinned supports (some thing similar to a gable frame) with a point load and a moment at the ridge. To further simplify, it could be two member rigid frame(arch) with pinned supports with a point load and a moment at the ridge(crown).
RE: Free standing stair
Personally, I think the key to making this work is to ensure the transfer of forces through the landing.
In this case, the 2 members (stringers) are not in the same plane, but offset from each other forcing the landing to the "link" between the two.
RE: Free standing stair
Dik
RE: Free standing stair
RE: Free standing stair
There are some references on the Internet. Here is one link:
ht
You can get more by Googling "free standing concrete stairway".
BA
RE: Free standing stair
Looks like a two beer stair system to me.
Mike McCann
MMC Engineering
http://mmcengineering.tripod.com
RE: Free standing stair
http://jce-ieb.org.bd/pdfdown/ce290102.pdf
RE: Free standing stair
Dik, Wanda and Family
RE: Free standing stair