concrete pouring in cold temperatures

huangyhg

concrete pouring in cold temperatures
hello all,
we will be pouring concrete in cold temperatures (5 degrees celcius) and was wondering if it is necessary to have hording in place? i remember from school that the ideal temperature for curing is 23 + or - 4 degrees celcius. at what point would hording be necessary as opposed to just taking precautions on the negative effects of the early strength of concrete when pouring in cold weather.
thanks,
clansman
concrete work a +5 c., does not require any special care. see "cold-weather concreting", out-of-print document from the portland cement association, on this page of my website:
the air temperature is not as important as most people think. the temperature of the concrete is the critical point.
the +5 c is really not a cold temperature since concrete will be warmer and does generate heat as it cures.
aci has very good recommendations.
dick