Question

Based on grain distribution analysis, the $D_{10}$, $D_{30}$ and $D_{60}$ values of a given soil are 0.23 mm, 0.3 mm and 0.41 mm respectively. As per IS code, the soil classification will be

• A. SW
• B. SP
• C. SM
• D. SC

Answer 1

The correct option is B SP

Coefficient of uniformity,

$C_u=\frac{D_{60}}{D_{10}}=\frac{0.41}{0.23}=1.78$

Coefficient of curvature,

$C_c=\frac{D_{30}}{D_{60}\times D_{10}}=\frac{{0.3}^2}{0.41\times 0.23}=0.95$

$Forwellgradedsand1<C_c<3and{C}_u>6asISclassification.Soitisapoorlygradedsand.$