Concrete Joist Floor Fireproof Cracking

[Structuralchick]

I am currently working on an existing structure with concrete joist floors. The I-beams supporting the concrete slab are wrapped with wire mesh. The wire mesh is supporting about 3" of concrete, for fireproofing, below the I-beam. There is a crack that runs below the length of the steel beam (in the area of the fireproofing). I have calculated that the wire mesh has enough capacity to carry the concrete but the occupants of the building find the crack unsightly and would like to cover it. I was wondering if anyone has any ideas of how to seal the crack with some type of product that has an appropriate capacity in case the wire mesh was to fail. Also the product needs to be fire resistant. Please let me know if you have come across this same problem or have some type of solution. THANKS!!!!

 

[youngstructural]

How big is the crack? If you're completely certain that it's not showing you anthing of concern (like unexpectedly high deflections in your steel beam or some other sign of overstress), you can probably just use some trowlable concrete patch product. There are several manufacturers making appropriate products, but I would highly recommend asking Sika about what you should use. They have a good product line (personal opinion) and excellent service (personal belief).

Good luck,

YS

B.Eng (Carleton)
Working in New Zealand, thinking of my snow covered home...