Civil Engineering - Soil Mechanics and Foundation Engineering - Discussion

Theoretically, a pure clay would have a value of 0° and Π would rise with increasing sand content and density to approximately 40° for a compact sandy loam soil. Loose sands range between 25 to 30°. As pure clays are rarely found in topsoils the typical value for a \'clay\'
soil would be in the range 5 to 10°

For Clay, the range is 5° - 10°.

5° - 10° is correct.

Theoretically angle of internal friction for clay is 0°.