I have used slag in the concrete mix (50:50) with very good experience with lower heat of hydration.

In Kuwait, they used ice and refrigeration lines very successfully especially during placement in summer time.

Regards,

Lutfi
www.cdeco.com

Post cooling of concrete gravity dams is a commonplace thing and is very simple in installation. Basically a network of iron pipes are embedded in concrete and lateron cool water is pumped through the pipes to cool off the core of concrete (sometimes for one year or more!).

You need to be careful that "chilled" water is just 5-10 degree C cooler than ambient, not more. Moreover in design take into account the amount of concrete consumed by these pipes (loss of section) as it may go subtstantial. Also look for any relative settlement in different sections of mass concrete as it may snap your pipes. If this is case, provide a __O__ loop in pipes to take large deflections.

Ciao.