Cool weather is here! Making and placing concrete in cold weather requires special attention by both the ready mix concrete producer and the contractor placing the concrete.

Cold Weather Effects on Concrete

• Slower cement hydration, resulting in increased setting time
• Slower strength gain
• Potential for damage due to freezing

Concrete Contractor

• To help improve the setting time of their concrete, contractors can order accelerator – chloride or non-chloride based – as appropriate
• Need to have materials and equipment to protect the concrete during and after placement to protect from freezing and retain heat generated by cement hydration – insulated blankets or tarps have been used successfully for this
• Test cylinders need to be stored inside a heated area, or in insulated boxes, maintaining temperature between 60°F and 80°F for the first 24 hours prior to transportation to the testing lab
• The minimum and maximum temperatures in the storage area are required to be measured and recorded, per ASTM C31 requirements

For further information, please refer to ACI 306 Guide to Cold Weather Concreting.
If you have any questions or concerns, please feel free to contact Point Ready Mix.