Where Should You Measure Concrete Temperature?

The best recommendation is to measure the temperature in the spots where you expect the most extreme temperatures, both cold and warm:

Measuring Lowest Temperature in the Concrete

The spots with the lowest temperature development will have a slower hydration and thereby a slower strength development. This means that these spots are at increased risk of early frost and even if these will reach more or less equal strength in the end (studies do show small variations ), it would take a longer time. Therefore, it is a good idea to monitor the temperature and strength development at these spots. It is important to remember these spots both in your planning (simulation) and in your control (sensor readings), as you need to make sure that they reach the strength before removing the formwork.

You will often be able to find these spots in:

Measuring Highest Temperature in the Concrete

The largest temperature stress occurs when you have a cold spot (described above) and a warm core temperature. You normally don’t want more than 10-20C differences in a cross section of your concrete. If you exceed these,  the risk of thermal cracks will increase. The cracks also are a result of much shorter exposure of sudden temperature variations, where stresses suddenly can occur. 

The temperature stresses are often highest in connection with:

In addition to monitoring to reduce risk of cracks, you might also take the following aspects into consideration, as you could benefit from additional monitoring to cover aspects like: