Acid etching with Muriatic acid
Earlier this week we started an epoxy flooring project (half existing concrete half new concrete). Just as we always do, working in 10x 10 ares, we mixed a 1:20 acid/ water solution, applied acid solution, scrubbed with a black pad, neutralized with ammonia (1:3 solution), scrubbed, and vacuumed (mechanical profiling was not an option because of being a laboratory environment). We completed the existing slab with no issues. Upon starting on the new slab, when we vacuumed, the slab began delaminating. We thought that it was only one area so we continued. The slab continued delaminating so we stopped and contacted the owner (working directly for owner and not GC). The entire slab is delaminated.
The next day we had a meeting with the Engineer, GC, owner's rep, concrete guy, and concrete supplier. They all preceded to say that the acid caused the delamination. At first I thought they were joking, but they were very much serious and asked how I was going to fix it (my expense).
After doing extensive research, I can not find another instance of this happening or a manufacturer warning of this possibility.
Does anyone have any experience with this happening or ever heard of muriatic acid causing delamination?