What should the oven temperature be when drying aggregate to constant mass?

The appropriate oven temperature for drying aggregate to a constant mass is 230°F (+/- 10°F). This temperature range ensures that the moisture content of the aggregate is effectively removed without overheating the material, which could potentially alter its properties.

Drying at 230°F is a standard in various testing specifications, such as those from ASTM, as it strikes a balance between sufficient heat to evaporate moisture and avoiding damage to the aggregate's particles. Maintaining the specified range is essential to ensure reliable and consistent results in material testing.

The other options, while close in temperature, do not align with the standard requirements for drying aggregate. For example, lower temperatures may insufficiently dry the aggregate, leaving excess moisture that can affect weight measurements and subsequent test results. Higher temperatures could lead to thermal degradation of the aggregate, impacting its performance in concrete mixtures.