Which ground condition qualifies for performing a standard count?

• A. Gravel
• B. Asphalt, concrete, or greater than 100 pcf material
• C. Sand
• D. Clay

Answer: (B)

The main idea is that standard count is used when the material isn’t a typical soil and can’t be tested with the usual density methods. Asphalt, concrete, or any material with a unit weight over about 100 pounds per cubic foot is too dense or bound for standard field density tests, so a standard count is the appropriate method to evaluate placement. Gravel, sand, and clay are soils that standard density tests can handle, so they don’t require the standard count.