Correct Answer - Option 2 : 55.5%
Concept:
Dry density of soil:
\(Dry\;density\;\left( {{γ _{dry}}} \right) = \frac{{{G}.{γ _w}}}{{1 + e}}\)
Where, γw = Density of water
e = Void ratio of soil
Relationship between e,s,w, and G
Se = wG
Calculation:
Given, G = 2.70, γw = 1 gm/cm3, w = 12 % = 0.12
Dry density = 1.705 gm/cm3
\(Dry\;density\;\left( {{γ _{dry}}} \right) = \frac{{{G}.{γ _w}}}{{1 + e}}\)
\(1.705 = \frac{{{2.7}\ ×\ {1}}}{{1 + e}}\)
1 + e = 1.583
e = 0.583
Relationship between e,s,w, and G
Se = wG
S × 0.583 = 0.12 × 2.7
S = 0.555
S = 55.5 %