If fine aggregate is wetter than SSD, what does AASHTO allow for using a mechanical splitter?

When fine aggregate is wetter than the saturated surface dry (SSD) condition, AASHTO guidelines provide specific protocols to ensure accurate sampling and handling. In this context, the use of a mechanical splitter becomes important for achieving a representative sample without introducing additional moisture, which could affect the testing accuracy.

The choice indicating a preliminary split with chute widths set at 1.5 inches or greater is allowed because wider chutes can help prevent excessive moisture from influencing the reliability of the sample being taken. When using a mechanical splitter under these conditions, ensuring that the chute width is sufficient allows the finer particles to pass through without becoming overly compacted or retaining moisture. This step helps maintain both the integrity of the sample and adherence to testing standards.

By allowing a preliminary split with the specified chute widths, AASHTO helps mitigate the effects of excess moisture while also facilitating the process of obtaining a representative sample for further testing. This attention to detail is crucial for accurate results in soil and aggregate testing, where moisture content can significantly influence material properties.