Concrete curing sounds like a simple process, just combine the cement with water and wait for it to dry, right? Wrong! To maximize the strength of the concrete, you’re going to have to control the moisture and temperature, so plan ahead of time.When monitoring the concrete curing process, besides time, two main factors come into play: the ambient weather conditions and the temperature of the concrete mixture.
Check the Forecast
First things first, if it’s hot enough where you don’t want to leave the comfort of your air conditioning or cold enough that you need to put on a hat and gloves, you shouldn’t lay concrete!
It’s advised that concrete be cured at a moderate temperature between 50 °F – 90 °F. In a perfect world, the temperature of fresh concrete should be above 50 °F, but cured and maintained at 50 °F. But if you can’t hit the 50-degree mark spot on, concrete cured within these temperatures will outperform +90 °F concrete in strength and durability.
Laying concrete is easy to do during daylight, but when concrete is poured during the day, the cooling of the surface during the night can cause cracking. One technique is to pour during the night. This allows the concrete to cool and then increase in temperature as the day begins, giving the concrete more time to strengthen without cracking under tension.
Test the Concrete
To ensure the temperature of the concrete stays within the acceptable levels, thermocouple data loggers are recommended for continuous monitoring. Before pouring the concrete, one or more thermocouples can be securely placed to measure and record temperatures throughout the curing process.
Maturity testing is commonly conducted to help estimate the strength of the concrete through temperature measurements over time. Keep in mind, temperatures reached during the early stage of concrete curing directly affect the final strength and performance.
Concrete curing for a longer duration increases the strength and durability. The American Concrete Institute suggests that concrete should reach its ideal strength after 7 days of curing at 50 °F or 3 days at 50 °F for a high early-strength concrete mixture.
For more information regarding thermocouple data logging solutions for continuous temperature monitoring throughout the curing process, click here.