drilling numerous holes for hilti epoxy on existing elevated slab

[delagina]

I have an existing elevated slab, 1'-3" thick with reinforcement top and bottom.
I'll be drilling numerous holes for threaded rod hilti epoxied to connect structures (not heavy) on top of it.
I'm not concerned about load/bending stress, I'm more concerned about the effects of drilling numerous holes some are close to each other.
Elevated slab is many decades old but in good condition (no huge cracks).

Any good reference or advice regarding this.

 

[hokie66]

Use a percussion drill, not a core drill. If you hit a bar, move over.

Now, if this is a prestressed slab, you should be more careful. Locate the tendons first, and avoid.

 

[NorthCivil]

this could all be a concern, or not.

how big are the holes? how close together are they? you say you are drilling to the top of slab - im guessing this is the compression face, so drilling a hole shouldn't trigger a crack to run along the whole length of the slab.