RCC stair in Steel Structure.

[KAMAL HOSEN]

Hello Everyone.
I'm designing a two storied Steel industrial building. Can i provide RCC stair there ? with steel I beam and column ? if yes then what should be the construction process. For lower suppert. it will get wupport from Grade beam or PL slab, for the upper support reinforcements of RCC stair will connected directly to reinforcements of decking slab. I think no problem with that. But what will be about mid landing ? i got two column in the two side. how will mid landing slab rest ? additionally i can add a steel I section beam from I section column, but very confused about construction of RCC stair and rebar connection in mid landing. Can anyone show me a Ref. Drawing.

 

[HarshParmar]

Didn't get your question , is that you want to make free standing mid landing?

If yes, then it would be challenging without stringer beam cantilevering the half flight from Ground/Grade beam and half cantilever of the flight from the upper level but this would induce huge torsion on the grade/ground beam and beam at upper level and the stringer beam would have significant depth.

Moreover on using steel-concrete composite-

In my opinion, it is possible but generally speaking, engineers do avoid this and practice is to use precast stair in industries with steel and column in US and UK. And if still wish to do it, look for steel-concrete composite construction system, which is steel deck on steel beam welded with shear studs, but am afraid and unsure if it would make any saving on soffit slab as it won't reduce the soffit slab depth except formwork and formwork erection time, and the reason for this, I presume the behavior of composite deck slab is inclined load can be complex.

Though this is my opinion, and I am relatively fresh so might be an amateur reply, but would love to know the solution how you did it finally.

 

[KAMAL HOSEN]

here is the details

 

[HarshParmar]

Architectural section shows, that the mid landing doesn't touch the window and it doesn't have any wall on top of it. Is the wall brick masonry 10" thick ? is the mid landing is getting cantilevered from the two columns ? as the sketch shows that column are present at start and end of flights.

 

[KAMAL HOSEN]

Mya be. it's just a sample i collected. My question is how we can make cantilever from steel column to rcc slab,,, ha ha ha

 

[HarshParmar]

In this case, the steel box section beam at the end of the flight to be supported by column, and cantilever slab on it. This box section can have cantilever brackets welded to box section extending till the edge of the mid landing ,and mid landing slab can rest on this brackets is the most easy solution I can think of. Reason for box section is that they are good at mitigating torsion which would arise out of cantilever slab. Still might have to use shear connectors (not necessarily welded) on top of box section and cantilever brackets to connect the slab with steel. Attaching different types of shear connectors here, if you are not intending to design as a composite still might help to have connection between steel section and concrete slab (though this area is still daunting for engineering). Hope this helps.

 

[dik]

Industrial steel building; can you use steel stairs? Concrete pan treads and landing or maybe metal grate? Likely be easier and less costly.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[BulbTheBuilder]

Just as Dik mention, for industrial structures we typically use steel. That should make things easier for you. What is driving the need for concrete? Is that a requirement for your school project?

 

[KAMAL HOSEN]

@bulb & dik, This is the requirement.

 

[dik]

Something like... a bad requirement, IMHO... You can tell your instructor that real engineers think this is a bad idea...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[BulbTheBuilder]

You can have a grade beam with starter bars for your first flight. Add beams to the columns for mid-height landing with the deck spanning 1-way (just like your stair). The top will be connected to the floor slab at the elevator level.

Keep in mind, don't do this real life.

 

[KAMAL HOSEN]

In real life, is it impossible to do that? Please explain to me. I really wanna know about that. Thank you So Very Much.