Slag set time in cold weather

[yahoo123]

Can someone tell me how much slag affects the set time of concrete?

I asked for 15%-25% slag replacement because Type II cement is not readily available in the area. This is for a digester tank containing wastewater. But the concrete supplier does not want to use slag because it is harder to obtain than flyash and he said the outside temperature is 33degrees F.

How does slag compare with flyash in terms of set time?

 

[concretemasonry]

No question about the retarding effects or slow strength gain when you are using fly ash and slag. The cool weather temperatures magnify the effects, no matter what the concrete temperature at placement.

Even though you may get a 28 day cylinder strengths specified, the actual site concrete at that time may be substantially lower because testing lab cylinder curing is not meant to be representative of the site curing. It just can take lower to cure and obtain the desired properties.

Slag could be a little difficult to get in some areas because it is really a waste product that has found a performance home, but not an economic niche in all areas.

 

[yahoo123]

but how does cure time compare between slag and fly ash?

 

[oneintheeye]

look at ciria report 93 and 660 I believe on formwork striking times and thermal cracking. this is very useful in looking at water retaning structures. setting time for replacement mix is increased not sure without referencing reports difference between fly and slag though there is a diff.