Vent: That 'non-shrink' grout is shrinking on my pads

I poured a 4 inch slab at a job in Reno last month, used the bagged non-shrink grout the spec called for, and now I'm seeing 1/8 inch gaps at the edge of three precast pads. The vendor swore it was fine for exterior work, but we got a hard frost two weeks after placement, and the stuff pulled away like it was nothing. I've done this trade for 11 years and never seen this product fail that fast, even with proper curing blankets. My supplier says it's a bad batch, but I'm not buying it, I think the mix design has too much air for cold weather. Anyone else see this on a recent pour, or am I the unlucky guy who gets to warranty this mess?

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angelacooper3d ago

Reno's had three hard freezes in the last two weeks, so that timing lines up too well. Even with blankets, that product wasn't meant to take a frost that quick. I'd bet on the mix design before I'd blame the batch, sorry you're stuck with the call.