Effects Of Cold Weather On Concrete Curing

Be prepared to handle more bleed water than is typical in regular concrete placement.

Effects of cold weather on concrete curing.

For well proportioned concrete mixtures this is typically within 48 hours of placement when the concrete temperature is maintained at 50 f. A delayed setting when the temperature is falling to about 5 0 c or below the development of strength of concrete is retarded compared with development at normal temperature. Damaging effects of cold weather concreting. If your concrete isn t protected with concrete curing blankets after it s poured it may cool too rapidly slowing the chemical reaction.

Following deleterious effect may occur due to cold weather concreting hydration will be hampered. Concrete can resist the effects of one freeze thaw cycle as long as it is properly air entrained not exposed to an external water source and has reached a compressive strength of 500 psi. Freezing of concrete at early stage. Poor finishing techniques can also doom your slabs.

Concrete placed during cold weather will develop sufficient strength and durability to satisfy the intended service requirements when it is properly produced placed and protected. Curing in cold weather will be different as in this case the biggest concern will be the maintaining of an adequate and conducive temperature for hydration. In the absence of special precautions the effect of cold weather concreting may be as follows. Except in heated protective enclosures little or no external supply of moisture is required for curing during cold weather.

When the temperature is falling to about 5 0 c or below the development of strength of concrete is. Depending on the actual ambient temperature protection of a concrete placement may require the use of windbreaks enclosures or supplementary heat. The protection period is defined as the time required to prevent concrete from being affected by exposure to cold weather. For massive members the heat generated by the concrete during hydration will be adequate to provide a satisfactory curing temperature.

Concrete poured and placed in cold weather has a much slower setting and curing time so bleeding will also start later than expected. If the temperature is too cold the concrete may not have reached a minimum strength of 500 psi soon enough to resist the effects of freezing temperatures. The exposure of concrete to cold weather will extend the time required for it to reach initial set which may require finishing crews to be available for a longer period.