Gypsum Floor Decking

[SteelPE]

I have an existing mezzanine that I need to evaluate the capacity of. The mezzanine uses what looks like prefabricated gypsum panels that are supported by open-web steel joists. The panels are approximately 2" think and span 3'-6" +/- (steel joist spacing).

Does anyone have any information on these panels and their load capacities?

view from underside

view from top of mezzanine

cross section view of panels

 

[port125]

I ran into these same panels for the first time as well maybe two weeks ago. Mine were used for roof framing.
There is a similar product apparently still available by Martin Fireproofing. They have load tables (attached)
The Gypsum ones were possibly by a company called US Gypsum. I did not have luck finding load tables on-line. (2015 article attached)they mention a US gypsum specification guide 1971.

https://files.engineering.com/getfi...46f8-8e12-b0ab394dbac4&file=2015-12-hogan.pdf

https://files.engineering.com/getfi...081489738a&file=Steel-Edge-Creteplank-web.pdf

 

[lexpatrie]

Those look like a Bulb-T system.

https://iibec.org/wp-content/uploads/2012-10-hogan.pdf

Not sure they were ever approved as flooring, they are a bit low capacity and don't feel very ductile to me, then again, neither does Tectum. I know at one point I found some information on them, including some diaphragm testing? These are more of a roof plank system to me.

A few links -

http://d3110379.u38.hosting-advantage.com/wp-content/uploads/2013/12/NRDCA-500.pdf

https://www.nrca.net/Technical/PDF?id=18692&k=108997

https://ascelibrary.org/doi/abs/10.1061/JSDEAG.0001424

Diaphragm strength:

https://www.iitk.ac.in/nicee/wcee/article/10_vol6_3347.pdf