Stair Stringer Connection to 6" Structural Slab

[courtnvm]

Okay, I have a fun and interesting challenge. I am providing calculations on a stair that has the stair stringer attaching to a 6" structural concrete. The steel fabricator has fabricated and installed a mirrored image of this stair. They are proposing to connect the stringer to the 6" slab using a single angle connection. The single angle connection is comprised of an L8x4x1/2 with (2)3/4" diameter adhesive anchors. The anchors are 4" apart in the horizontal direction. When I do the calculation for the anchors I am getting quite high bolt forces due to the eccentricities. Am I correct in assuming that the bolts would have eccentricity due to the single angle connection. Or are stairs typically thought of as being restrained at this type of connection. My concern is that another engineer has provided calculations on the same connection on a similar stair. I want to make sure that I am thinking correctly.

Location of Holes in 6" Slab:

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0 0
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Val

 

[JedClampett]

I wouldn't do it. The minimum edge distance for a 3/4 inch is one half the embedded depth (Hilti RE500, ICBO Report No. ESR-1682). With that small of an edge distance, you're probably talking about an unreinforced edge, susceptible to breaking out. Plus, for anchors that close, you're also reducing for spacing.
I would ask if the fabricator could extend the stringer with a horizontal dapped end to bear on the slab.