Pencheck stairs

[hoshang]

Hi all
This thread:

https://www.eng-tips.com/viewthread.cfm?qid=479910

There is an old form of construction, known as a pencheck stair, which can be used to support a stair from a masonry wall without columns. Such stairs appear to ‘cantilever’, but as inferred by the original question, they do not do so. Pencheck stairs work by combined bearing and torsion and were originally constructed from stone; so no issues with concrete.

I have conserved several examples in old buildings. You can find an explanation of how pencheck stairs work at the web address below.

https://load-paths2020.blogspot.com/search?q=Pench...

How the three component parts of the load path in the link above posted by Menai be used in an RC stair?

 

[phamENG]

Unless you're casting each piece individually and putting them in place, I'd say they don't work for reinforced concrete. If you want to accomplish that as RC, follow KootK's advice in that thread.

 

[KootK]

If one could construct the wall such that the CIP stairs were recesssed into it as the stone stairs would have been irecessed into a masonry wall, I'm sure that this would work great, surely better than stone. The difficulty would come in how to form the wall to accomplish that economically. Concievably, one could post install dowels to deal with the torsion via shear friction. Myself, I'm not sure that I'd have the ovaries required for that kind of badassery.

 

[KootK]

This is a solid discussion of how the "rebate" works to ameliorate the need for torsion capacity at the wall connection.Link

 

[hoshang]

Unless you're casting each piece individually and putting them in place, I'd say they don't work for reinforced concrete.

Hi,
Can they work for slabless stairs?

 

[hoshang]

Hi
please find the attached link:

https://www.google.com/url?sa=i&url=https://

http://www.kindpng.com/imgv/oJJwJi_...ved=0CAwQjRxqFwoTCND8r77R4PoCFQAAAAAdAAAAABAi

Can pencheck stair work for slab stair?
If you look at the reinforcement detail in the link, can the vertical rectangle section be considered as the torsion component part of pencheck stair? Also can the the overlapped vertical & horizontal rectangle section be considered as the bearing component part of pencheck stair?