Is a composite sample of concrete necessary for temperature determination?

The correct answer indicates that a composite sample of concrete is not necessary if only temperature is the aspect being measured. This is because temperature is a uniform property throughout a batch of concrete, particularly when dealing with freshly mixed concrete. As such, taking a single temperature measurement at a representative location is generally sufficient to reflect the overall temperature of the concrete mix.

When measuring temperature, it is typically done at a specific point in time and place, and it does not require the homogeneity that composite sampling would provide, which is more critical for assessments of properties like strength or composition that require homogenization of the materials. Therefore, for the straightforward purpose of determining temperature, any representative location can yield an accurate measurement, making the composite sample unnecessary in this context.

The other options imply situations where a composite sample might be required for reasons that do not pertain specifically to temperature measurement alone, which emphasizes that temperature does not necessitate the complexity of composite sampling.