Industrial Slab delamination

Samples couriered for evaluation.
Void (bleed channel) with fine particles of sand and cement. (Petrographic photo
Porous mortar section with voids (bleed channels) (Petrographic photo)
Large air void (bleed channel) with fine sand particles and cement.
Entrained air voids in fairly dense paste. (Petrographic photo)
Another dense concrete area with bleed channels. (Petrographic  photo)

Manufacturing Facility, Hagerstown, Maryland

Delamination of sporadic areas in a newly built 77,000 square feet manufacturing floor slab prompted an evaluation. A sample taken from a substantially damaged area and one from a well performing area were sent to our laboratory. Petrographic analysis was used to point to re-tempering, excessive air and above normal water content in concrete as contributory factors to the problem.