Wetting of the mud mat prior to placement

[btv189]

During a recent concrete pour we did not wet the mud mat prior to the placement of concrete. The temperature outside was below freezing putting us in cold weather concreting. My question is what effect does this have on the slab itself? I believe its minimal due to the outside temperature and the humidity. ACI 318 or 306R does not include this as part of their preparation prior to concreting, 301 calls this out but does not identify whether this should be done in cold weather.

 

[darthsoilsguy2]

read up on the ACI definition of cold weather concrete.... it sounds like you might not understand the trigger by how you phrased this. i believe there are references in multiple codes/specs/standards to not place concrete on a frozen subgrade including aci-306r. A mudmat below 32F is that. if the thermal mass of the subgrade drops the concrete below 35F before initial set, i bet against the slab. there are a lot of variables missing here to say more (subgrade temp prior placement, member thickness, conc temp @placement, air temp @placement, time of placement, high-low forecast (now historical data), protection methods in place, and in an ideal world... check-up surface temps after placement.

 

[HockeyPuck]

Let me ask: What is the concern that you have? Is it whether or not a specification clause was adhered to? Or is it whether there is a functional issue because of the conditions at the time of placement?