What are the three ways to reduce aggregate sample size according to C702?

The correct method for reducing aggregate sample size according to ASTM C702 involves using a mechanical splitter, quartering, and miniature stockpiling.

Using a mechanical splitter allows for a precise and efficient division of the aggregate sample into two or more smaller portions without causing changes to the material's composition. This method ensures that the remaining portions of the aggregate maintain a representative sample for testing.

Quartering involves dividing the sample into four equal parts, then taking two opposite quarters to create a smaller sample size. This technique helps in reducing the quantity of the original sample while ensuring the selected portion is representative of the whole.

Miniature stockpiling, although less common than the first two methods, refers to creating a small pile of aggregates from which further samples can be taken, ensuring that the sampling process remains efficient and representative throughout.

Other choices involve methods that do not align with the standardized practices given in C702. For instance, crushing and grinding could alter the physical properties of the aggregates rather than just resizing them, which is not recommended in proper sampling protocols.