According to AASHTO sampling procedures, how should samples typically be composed?

• A. One single increment
• B. A mix of different materials
• C. Multiple increments
• D. Depends on the test being conducted

Answer: (C)

Samples should typically be composed of multiple increments to ensure a representative sample of the material being tested. This approach helps to minimize variability and provide a more accurate assessment of the overall properties of the material. By combining different increments taken from various locations within a batch or lot, the resulting sample reflects the average characteristics of the entire material, rather than being influenced by localized variations.

In contrast, using a single increment would not provide a comprehensive view of the material's properties, as it could be biased or not representative of the whole. A mix of different materials may create confusion about the sample characteristics, especially if the intent is to analyze a specific material. While the sampling method may depend on the test being conducted, the common practice in AASHTO procedures prioritizes the use of multiple increments for consistency and reliability in testing results.