Concrete stair deflection

[JStructsteel]

Got a concrete stair, deflection ratio is L280. Section 10" thick. Total deflection is 1"
Do you folks find that acceptable, or should I be going for higher on a stair?

 

[phamENG]

Total load, I'm assuming? Interior or exterior? Main evacuation route for the building?

Have you checked crack widths? That may be a good indicator. 1" feels like a lot of deflection in a concrete structure. But I also haven't done a lot of purely cast in place work.

 

[JStructsteel]

Total load. 100 psf live load. Interior stair, I would say a main route, in a school.

Have not checked crack width. I looked at a 11.25" section, that gets me to L420.

Floors are usually L360 LL, L240 Total.

 

[milkshakelake]

Does that include long term deflection? You can reduce the long term deflection by adding top bars, though it's unusual to do so. 10" is already very thick. L/280 is acceptable per most codes, I wouldn't worry too much about it. I'd say over 1" is unacceptable.