However, this high resistance doesn’t prevent it from freezing. The ACI definition of cold weather – during which protective measures should be taken – has been simplified to include any actual or predicted drop in air temperature below 40 degrees Fahrenheit during a cold weather concrete protection period – the time during which curing concrete is recommended to be protected during cold weather. Methods for gradual cooling of concrete include loosening the forms while maintaining cover with plastic sheeting or insulation, gradual decrease in heating inside an enclosure, or turning off the heat and allowing the enclosure to slowly equilibrate to ambient temperature. Chapter 6 of ACI 306 describes measures the contractor must take before placing concrete in cold weather. The ACI or American Concrete Institute says in their ACI 306R-10 “Guide to Cold Weather Concreting that “cold weather exists when the air temperature has fallen to, or is expected to fall below 40℉ during the protection period*.” So if you find yourself grabbing a jacket on your way out the door, consider the air temperature before mixing, pouring, or placing concrete. The ready mixed concrete producer can control concrete temperature and furnish concrete to comply. It should be noted that the reduced temperature will lead to a slower rate of gain of strength of the concrete. The general category of “cold weather concrete” applies to a period of three days or more where specific conditions occur while concrete is exposed. Thus certain precautions have to be taken when concreting in cold weather. Special care must be taken when concrete is cast in winter. It is also important to prevent rapid cooling of the concrete upon termination of the heating period. The necessary degree of protection increases as the ambient temperature decreases. www.cement.org, 2020 Energy and Environment Award Winners, 2020 Chairman’s Manufacturing Performance Award Winners, 2019 Chairman's Safety Performance Award Winners, 2019 Chairman’s Manufacturing Performance Award Winners, Storm Water Management by Pervious Concrete, Technical Information on Pervious Concrete, Leadership in Energy and Environmental Design, State & Market US Summary (13 Categories, 1 Year), State & Market Trend (46 Categories, 20 years), Construction PIP by State (23 Categories, 20 years), Resiliency Potential in the Wildfire-Prone Single-Family Market October 2020, The Potential Impact of Tariffs Levied Against Chinese Cement, Railway-Related Cement Consumption Outlook, Trump Infrastructure: Potential Taxpayer Savings from the Use of Life Cycle Cost Analysis (LCCA), Attitudes & Perceptions Study: Soil Cement, FDR and RCC Pavement Market, Long Term Cement Pavement Consumption Outlook, Energy-Related Cement Consumption, September 2017, Airport-Related Cement Consumption Outlook, July 2017, U.S. Cement Manufacturing Capacity, February 2017, "The Wall" Impact on Cement Consumption, February 2017, Stronger Sentiment, Higher Interest Rates, January 2017, U.S. Portland Cement Industry: Plant Information Summary, COVID-19 State Resources and Environmental Policies, Sustainable Cement & Concrete Manufacturing Toolkit, Sustainable Cement & Concrete Construction Toolkit, Design and Control of Concrete Mixtures Course, Troubleshooting: Solutions to Concrete Field Problems, Mill Grinding Course and Kiln Process Program, Masonry Walls and the Importance of Mockups, Verifying Compressive Strength of Masonry, The Masonry Society Becomes Sole Sponsor of Code and Specification, Special Inspection in the Codes and Standards, Placing Joints in Concrete Flatwork: Why, How, and When, The Difference Between Curing and Drying Concrete. The objectives of cold weather concreting practices are to: a\) prevent damage to concrete due to freez\ ing at early ages; b\) ensure that the concrete develops the recommended strength for safe removal of forms; c\) maintain curing conditions that foster normal strength development; d\) limit rapid temperature changes; and e\) provide protection consistent\ with intended serviceability of the structure. Per the American Concrete Institute, here is what those different weather conditions entail: — An average daily air temperature lower than 40°F. Although cold weather concrete placement poses its challenges, if done properly, concrete placed at lower temperatures will benefit from the slower curing times. Avoid construction delays when the temperature drops with climate control technology from Wacker Neuson. If the water in the young concrete is allowed to freeze, the concrete will be damaged to such an extent that it is unfit for use. 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