effect of temperature difference between concrete and ambient temperature on concrete

Dear All,
What happens when difference between temperature of concrete and atmosphere is too high i.e. Concrete temperature 34 degree (at the time of pouring) and atmosphere temperature is 10 degree or less? any special effect will occur during concrete or after concrete. what precaution measure shall be taken during the concreting and after concreting?
 

Dnyan Deshmukh

Staff member
Concrete temperature mostly equals to the temperature of water unless the aggregates are heated due to sunlight, fresh cement has temperatures above 50 degree etc.

The difference in temperature affects the hydration process and also leads to evaporation of water from concrete surface which leads to shrinkage cracking in it.

The lower atmospheric temperatures near to freezing point also impacts the concrete due freeze and thaw actions.

I worked in area where temperatures goes above 40 Degree, here we do take care to ensure reducing evaporation and maintaining surface temperature by doing initial curing once the concrete start setting (Initial Setting).

Initial curing can be done by sprinkling water, covering concrete with wet hessian cloths or wrapping it with plastic sheets.

As i never worked in cold region, i do not have much idea on it but in cold region concrete is protected from freezing by heating the form surfaces.