Steel staircase

[mats12]

Hello, im doing this for the 1st time.
Id like to know if the detail A and B are alright?
Is there better way to do it?

tnx for help

 

[BSVBD]

It "looks" acceptable!

I would increase the spacing between your fasteners depending on what you are fastening to.

What are your fasteners and what material are you fastening to?

 

[jayrod12]

I'd also consider increasing the channel depth. Generally stair stringers are 250 or 300 deep to fit the treads.

 

[mats12]

Im fastening to the RC beam: 40/25 cm (edge of the concrete slab that is 18 cm thick).

Top/Bottom reaction is cca 12 kN.

I think if I choose 2x M14 (8.8) fasteners is more than enough. Only shear force is applied on fasteners or have I overlooked something?

 

[msquared48]

A few comments...

1. Use C12 channels for the stringers. Slope should be about 7:12... +-

2. Use an equal angle diagonal splice of the platform portion to the stringer, not a vertical splice, or the channel depths will not match.

3. Delete the bottom vertical leg, foreshorten the C12 stringer to maybe 8" at the base and weld a flat plate to the bottom for (2) anchor bolts.

Mike McCann, PE, SE (WA)

 

[BUGGAR]

Think about how the concrete anchors will be installed, before or after the stringers. If installed before, can the stringer(s) still be maneuvered into place over them? If installed after, is there room for the installation tool to install them? If they hit a rebar and have to move the anchor, what happens then?

 

[mats12]

Tnx for answers.

Should DETAIL A have ENLONGATED HOLES (vertically) for fasteners/bolts because of the concrete beam deflection?

msquared48 you mean like this?

 

[KootK]

I prefer horizontal slots at the bottom. It can be awkward to hang the stringers initially with slotted holes at the top.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.